CP-Rebopbebop
How big must the difference in electronegativity be to be considered a non-polar bond?
Any electronegativity difference less than 0.5 is considered a non-polar bond
What is atmospheric pressure?
Atmospheric pressure is the pressure that we feel on this planet by virtue of having an atmosphere (which contains moving gas atoms that hit and apply pressure to us.) This pressure changes with height. The higher you are, the lower the atmospheric pressure.
Which is the second quantum number?
Azimuthal (angular momentum) number, l. number determines the shape of the electron's orbital. Examples: A p orbital is associated with an azimuthal quantum number equal to 1.
Why do we care about the difference between laminar and turbulent flow?
Because laminar flow can be approximated to be a conservative system with no dissipation of energy to heat, sound, etc.
Describe the unique characteristics of alpha hydrogens?
Because of how loosely the alpha hydrogen is held, it is relatively easy to break the bond between it and the alpha carbon, generating a carbanion.
Describe the energy in phosphate groups?
Because of the close association of so much negative charge, phosphates are high energy groups and are often coupled with reactants to make them more reactive. The more phosphates (PP or even PPP) the higher energy the group.
What is the Delta G?
Delta G is the free energy change associated with something.
What is diffraction?
Diffraction is the spreading out of waves as they pass through a narrow opening or around an obstacle.
What is diffusion?
Diffusion is the spontaneous movement of molecules from high concentration to low concentration.
What is a dynamic equilibrium?
Dynamic equilibrium is when reactants are converted into products, but at the same rate at which products are converted into reactants, resulting in no net change in the substance and allowing it to remain at equilibrium.
What is the equation to calculate the strength of the electric field that is created between the plates of a capacitor?
E=V/d
What is the eluent?
Eluent is another name for the mobile phase in chromatographic methods.
What is External Validity?
External Validity refers to whether or not the causality you identified in your research can actually be generalized to the population you say it generalizes to.
What is the frequency factor, A?
Frequency factor is how many molecules collide per second.
Which form of radiation is most dangerous if it is outside the body?
Gamma rays are the most dangerous outside the body because they can penetrate the skin/clothes easily and cause damage within the body.
How do we write an equilibrium expression?
Given the balanced equation... The equilibrium expression will equal...
Where are the Alkali Metals on the periodic table?
Group 1
What are the two types of energy transfer?
Heat(thermal) and Work(mechanical)
Which component of a vector will cos(theta) give you? (horizontal/vertical and parallel/perpendicular)
Horizontal or Perpendicular
When a light ray refracts from one medium to another, how does its speed change?
If the second medium's index of refraction is lower, the light ray goes faster. If the index of refraction is higher, the light ray goes slower.
Where are metals found on the periodic table?
The left side and the middle.
What is a reaction mechanism?
In a reaction that is expected to take more than one step, the reaction mechanism is the proposed series of steps.
What is a single-blinded study?
In a single blinded study, the subjects do not know which group, experimental or control, they are in.
What is intensity of sound?
Intensity of sound is the average rate of energy transfer per area a sound wave makes on a surface.
Calculate change in entropy of a reversible process?
J/K is units
How does one calculate the equivalent resistance for resistors in series?
Just add them up
What is the general rule for common naming ketones?
Ketones are commonly named by listing the alkyl groups in alphabetical order, follwed by -ketone.
How do we name amides as substituents and parent chains?
Like all the other carboxylic acid derivatives, amides won't usually be substituents, but when they are, they are called carbamoyl- or amido- Amides are named by dropping the -oic acid of the parent name and adding -amide. The groups bonded to the amide nitrogen are designated N-
transverse vs. longitudinal waves
Longitudinal waves - parallel. Transverse waves - perpendicular
SI units of mass, length, volume
Mass - kg length - m volume - m^3
Between median and mean, which is more sensitive to outliers?
Mean is skewed more heavily by outliers than median.
What is molecular formula?
Molecular formula is the exact number of atoms of each element in the compound, without being reduced to simplest whole number ratios.
What kinds of molecules make good oxidizing agents?
Molecules that reduce well (i.e. attract electrons).
Sound
Must travel through a medium. Longitudinal wave and travels fastest through solids.
What are the units of electrostatic force?
N =1 *kg*m/s^2
Do products ever appear in the rate law?
No! Rate is dependent on the concentration of the reactants, so only they are included.
Does a molecule with polar bonds always exhibit polarity?
Not always. Remember, symmetrical molecules can cancel out the polarity in their bonds.
What is the number following the element name when describing an isotope?
The mass number. For example. Carbon-12 has a mass number of 12.
What are the most important IR spectra absorptions to know?
O-H bonds, broad peak around 3300cm-1 N-H bonds, sharp peak around 3300cm-1 C=O bonds, sharp peak around 1750cm-1
What are observational studies?
Observational studies are when you observe a population of some sort and take note of their outcomes. These are subclassified as 1. Cohort Studies 2. Cross-sectional studies 3. Case-control studies
What is the SI unit for resistance?
Ohms (Ω)
In which direction will a positive charge's electric field radiate?
Outward
Describe the shape of a p orbital?
P orbitals are dumbell shaped.
What does it mean to be paramagnetic?
Paramagnetic materials are made of atoms with unpaired electrons and net magnetic fields, but the atoms are randomly distributed and the net magnetic field within the material cancels out.
What is percent composition?
Percent composition is the percent by mass of a specific compound that is made up of a given element.
In an isolated system, describe the phases of the molecules?
Phase changes are an equilibrium, so in an isolated system given enough time, solid, liquid, and gaseous forms of the compound will exist in an equilibrium of some sort. Note: this equilibrium can so prefer one phase, such as solid, that you cannot see the tiny amounts of liquid and gas present.
Molecular bonds are made from overlapping atomic orbitals. What kind of bond do you get when parallel p-orbitals on adjacent atoms share electron density?
Pi bond.
What is pitch?
Pitch is our perception of the frequency of a sound. Each frequency will have its own pitch.
Describe Poiseuille's Law?
Poiseuille's Law is a method by which one can calculate the rate of flow through a confined space (or pipe) of some sort.
What does it mean to precipitate?
Precipitation is when a molecule does not dissolve but rather remains/goes to the solid phase.
What is pressure?
Pressure is force applied over an area. Force is perpindicular to the movement
What are the 4 variables that define the state of a gas?
Pressure, Volume, Temperature, and the number of moles of gas.
How do primary alcohols interact with oxidizing agents?
Primary alcohols are readily oxidized to Carboxylic Acids by basically every single oxidizing agent except PCC which is very weak. PCC will only oxidize a primary alcohol to an aldehyde.
List the functional groups in terms of increasing priority.
Priority increases as you go up the list.
What conformation does cyclobutane take in order to reduce ring strain to as low as possible?
Puckered
What is pyrophosphate?
Pyrophosphate is the name of phosphate dimers. It is denoted PPi in biological contexts.
What is a quinone?
Quinones are the product of the oxidization of phenols. They are characterized by a ring systems with carbonyls. Some quinones are aromatic, but not all of them.
What is R and S absolute configuration?
R and S absolute configuration is a way of describing the configuration of a chiral center in a molecule without referring to something else to do so. In order to do this, one must complete a multi step process. Make sure you practice the process before test day.
From right to left, what are the basic colors represented in the visual spectrum?
Red, Orange, Yellow, Green, Blue, Indigo, Violet MNEMONIC: ROY G. BIV.
What are some good reducing agents?
Reducing agents get oxidized themselves, and therefore will have features that make them unattractive to electrons. Two main examples would be low electronegativity (sodium, magnesium, zinc, aluminum, zinc). And negative charge on an atom, usually the Hydride ion (H-)
What is reduction?
Reduction is the gain of electrons. MNEMONIC: LEO the lion goes GER. Lose Electrons Oxidized. Gain Electrons Reduced.
What is total internal reflection?
Remember, at the critical angle, the light that is being refracted is being bent all the way to the boundary of the two materials. If the angle of incidence is even higher than the critical angle, all refracted light will end up on the same side of the boundary, which is to say that it is actually being reflected. Therefore, total internal reflection is when you refract the light at such a wide angle that it just ends up reflecting. This happens when the angle of incidence for the light wave exceeds its critical angle.
What is reverse-phase chromatography?
Reverse-phase chromatography is basically identical to other forms of thin layer chromatography. The only difference is that the stationary phase is nonpolar and the mobile phase is polar. In normal TLC, it's the other way around.
Describe the shape of an s-orbital.
S-orbitals are spherical shaped.
What is saponification?
Saponification is the treatment of long nonpolar carboxylic acids (fatty acids) with lye to produce a salt with a nonpolar tail and a polar head. Must be done with a base
What is selection bias?
Selection bias is when the sample differs from the population in a non-representative way. This is most common in human subjects research.
Describe the C=O IR peak
Sharp peak around 1750cm-1. Usually pretty tall as well.
Describe the -NH IR peak
Sharp peak around 3300cm-1 usually shorter than OH peaks
Molecular bonds are made from overlapping atomic orbitals. What kind of bond do you get when orbitals overlap directly?
Sigma (or single) bonds.
When do we use simple vs fractional distillation?
Simple distillation is used for mixtures of liquids that have boiling points below 150 C and have more than a 25 C difference in boiling point. Fraction less than 25 C
Describe the bond strength of single, double, and triple bonds.
Single bonds, with their one sigma bond, are weakest. Double bonds, with their one sigma bond and pi bond, are in the middle. Triple bonds, with their one sigma bond and two pi bonds, are the strongest.
What kinds of covalent bonds can potentially form?
Single, double, or triple covalent bonds are all possible between atoms. It all depends on what that atom needs in order to acheive a stable octet with the electrons available to it.
Describe Sn1 Reactions
Sn1 reactions contain two steps. In the first step (the rate limiting step) the leaving group leaves, generating a positively charged carbocation (great electrophile!). In the second step, the nucleophile attacks the carbocation.
Describe Sn2 Reactions.
Sn2 reactions contain only one step. The nucleophile backside attacks the electrophile which simultaneously causes the leaving group to leave.
How do d and l relate to R and S?
So, R and S are enantiomers of eachother. So are d and l. But d doesn't necessarily mean R, and l doesn't neccessarily mean l. d and l have to be experimentally determined while R and S can be determined by just looking at a molecule. So, if the d enantiomer ends up being the R enantiomer, then the l enantiomer will be the S enantiomer. But if the d enantiomer ends up being the S enantiomer, then the d enantiomer will be the R enantiomer.
What is solvation a.k.a dissolution?
Solvation is the electrostatic interaction between solvent and solute molecules that causes ions to be separated from one another in solution.
How does solvation occur?
Solvation occurs when the electrostatic interactions between the solvent and the solute are strong enough to break the intermolecular bonds in the solute and separate the ions from one another.
What is speed?
Speed is a scalar quantity that tallies the length of distance travelled over time.
What is a stoichiometric coefficient?
Stoichiometric coefficients are the numbers we place in front of elements in a reaction to balance the reaction.
Describe the hydrolysis of amides
Strong acid activated amides can be attacked by water to perform a nucleophilic acyl substitution in which ammonia is the leaving group.
What is it called when a solid goes to a gas?
Sublimation
How does one calculate period?
T=1/f
What is the SI unit for magnetic field strength?
Tesla
What is the Hawthorne Effect?
The Hawthorne Effect, also called the observer effect, is the phenomenon where people change their behavior as a result of being knowing they are being observed. This is a type of bias.
What is the LUMO?
The LUMO is the Lowest Unoccupied Molecular Orbital. This is the lowest energy level that the electrons can be promoted to.
How do dielectrics affect isolated capacitors?
The dielectric will lower the electric field of the isolated capacitor, which will lead to a decrease in voltage and an increase in capacitance.
How do the components of vectors add when two overall vectors are summed?
The components themselves simply sum.
What happens if the solute-solvent interactions are not stronger than the intermolecular forces in the compound?
The compound will not dissolve.
What principle explains all the circuit laws?
The conservation of energy principle.
What is bond energy?
The amount of energy requred to break a bond by separating its components into their isolated gaseous atomic states.
What is the coupling constant?
The coupling constant, j, is a measure of how widely split peaks get when they split. This constant is unique to basically every splitting situation.
What is the law of reflection?
The angle that the incident ray makes relative to the normal will equal the angle that the reflected ray makes relative to the normal.
What physical properties affect capacitance?
The cross sectional area of the plates and the distance between them.
How do dielectrics affect capacitors connected to a voltage source (battery)?
The dielectric will reduce the electric field in the capacitor, which would normally lead to a decrease in voltage, but the capacitor is hooked up to an external voltage source, so it maintains its voltage. Instead, the decrease in the electric field in the capacitor will manifest itself as an increase in the charge on the plates of the capacitor.
What happens when a dipole is placed in an electric field?
The dipole will spin if necessary in order to cancel out its torques. An example is shown below.
What is the electro-motive force?
The electro-motive force is the potential difference between the two terminals of a cell. This potential difference is what drives the electrons through the wire of the circuit. Notice that this is not a force, but a potential difference. The name is a misnomer.
What feature of the reaction diagram corresponds to the delta G of the reaction?
The energy difference between the products and the reactants corresponds to the delta G of the reaction.
What is the equilibrium position?
The central point around which the wave oscillates.
What is the first law of thermodynamics in the context of Thermodynamics problems?
The change in the total internal energy of a system must be equal to the change in heat and work (because energy must be conserved).
What is Entropy?
The extent to which a system is spread out/unorganized. The more spread out/ the less organized the more entropy.
What happens if you shine light on a metal that has a higher energy than the work function energy?
The extra energy is converted into kinetic energy for the electron. So, the higher the frequency of the light shined on a metal, the higher the kinetic energy of the ejected electrons.
Current
"The movement of charge per unit time. Metals are good conductors because of there sea of electrons (conduction electrons) that are not bound to a nucleus and allows net movement of charge "
What are the possible values of ms?
+1/2 if the electron is spinning up and -1/2 if the electron is spinning down.
What is cohesion?
The force of attraction that the molecules that make up a fluid feel with other molecules of that same fluid.
What is static friction?
The force that exists between a stationary object and the surface upon which it rests.
When a light ray refracts from one medium to another, how does its frequency change?
The frequency of light is unaffected by refraction.
What is the fundamental frequency of a string?
The frequency of the first harmonic standing wave (n=1)
What is the fundamental unit of charge?
The fundamental unit of charge is the smallest discrete unit of charge that can exist. It is the charge on the electron(negative) and the charge on the proton(positive) it is equal to 1.60*10-19C Q=ne
What are the possible values of Magnetic quantum number?
-l to +l
What is Gibbs free energy equal to at equilibrium?
0
What is the vertical speed when an object reaches its maximum height?
0
What is the NMR shift associated with alkyl protons?
0 to 3 ppm.
What is a number raised to the zero equal to?
1
What are the standard conditions for measuring equilibrium, kinetics, and thermodynamics problems?
1. 25 degrees C or 298 K 2. 1 atm pressure 3. 1 M concentration.
What are some functional groups that commonly act as bases?
1. Amines 2. Amides
How do you assign R and S to a fischer projection?
1. Assign priority to the groups using Cahn-Ingold-Prelog Priority 2. Represent the molecule as a fischer projection. You may have to rotate the molecule to do so, remember, the arms of the molecule need to be coming out at you from where you're looking. 3. Use one of the two allowed rotations (180 degrees or anchor a carbon and rotate through the other 3) to get the lowest priority group (4) at the bottom of the cross. 4. Draw a circle from (1) through (2) to (3). If it is clockwise, then the configuration is R. If it is counter clockwise, then the configuration is S.
How are ketones named as substituents and parent chains?
1. Carbonyl substituents, whether they are aldehydes or ketones, are given the mane (oxo-) 2. Ketone parent chains replace the -e of the parent name with -one.
How are aldehydes named as substituents and parent chains?
1. Carbonyl substituents, whether they are aldehydes or ketones, are given the name (oxo-) 2. Aldehyde parent chains replace the -e of the parent name with -al
What are the two types of electrodes?
1. Cathodes 2. Anodes
What are the axes of an NMR spectra?
1. Chemical shift in units of parts per million, increases as it goes left, not right. 2. Absorbance, which corresponds to the number of protons. Chemical shift is an arbitrary unit that is used to standardize NMR spectra.
What are the three types of heat transfer?
1. Conduction 2. Convection 3. Radiation
What are the two types of calorimetry?
1. Constant Pressure 2. Constant Volume
What are the two types of equilibria?
1. Dynamic 2. Static
What are three common names associated with aldehydes?
1. Formaldehyde - Methanal 2. Acetaldehyde - Ethanal 3. Propionaldehyde - Propanal
What are the common names associated with carboxylic acids?
1. Formic acid (Methanoic Acid) 2. Acetic Acid (Ethanoic Acid) 3. Propionic Acid (Propanoic Acid)
What are the two types of electrochemical cell?
1. Galvanic (Voltaic) cell 2. Electrolytic cell
What are the two main types of substitution reactions?
1. Sn1 2. Sn2
What are the important points and lines of the phase diagram?
1. The solid<>gas equilibrium line 2. The solid<>liquid equilibrium line 3. The gas<>liquid equilibrium line 4. The triple point 5. The critical point
What are the 4 colligative properties?
1. Vapor pressure 2. Boiling point 3. Freezing point 4. Osmotic Pressure
What is a carboxylic acid?
A carboxylic acid is a molecule with a highest order functional group of a terminal carbonyl with an -OH group.
What is a coordination compound?
A coordination compound, a.k.a, a complex ion refers to a molecule in which a cation is bonded to at least one electron pair donor. This electron pair donor is often the solvent, like water.
What is a crest?
A crest is the highest point a wave reaches.
What is a molecule?
A molecule is a combination of elements.
What is a normal?
A normal is a line that is perpendicular to a surface.
What is a reduction potential?
A reduction potential is the potential change associated with a reduction reaction.
What is a semicarbazone?
A semicarbazone is a modified version of an Imine. In this molecule, the double bonded nitrogen has a N-C(O)-N moiety attached.
How much mass does an electron add to an atom?
About 1/2000th of a proton. Essentially the mass of an electron is negligible in its contribution to the mass of an atom.
What is acetone?
Acetone is the common name for propanone.
What is achirality?
Achiral molecules are molecules that have mirror images that can be superimposed on one another.
What are common dielectrics?
Air, glass, plastic, and ceramic.
Describe the characteristic properties of an amide bond.
Amide bonds undergo resonance stabilization between the carbonyl and the lone pair on the nitrogen. This stabilizes the bond nicely, locks it into place (no free rotation) and makes it very difficult to break. It's a good thing our amino acids are linked by these bonds because otherwise our proteins would just fall apart and twist around wildly.
What are the SI units of current?
Amperes
What is amplitude in the context of waves?
Amplitude is the maximum possible displacement for a wave.
What is an aminonitrile?
An amino nitrile is a molecule with an amino group and a nitrile group
What is an electrical dipole?
An electrical dipole is when 2 equal positive and negative charges are separated by a small distance.
What is an equilibrium?
An equilibrium is any situation in which there is no net change in the some property.
What is a charged atom called?
An ion. Ions can receive another name depending on if they are positively or negatively charged.
What does it mean to be isochoric(isovolumetric) and how does that affect the first law of thermodynamics equation?
An isochoric process is one in which no change in volume occurs. Without volume change (compression or expansion) there can be no work. U=Q
What should the change in total mechanical energy of an object be equal to when considering nonconservative forces?
The change in total mechanical energy will be equal to the work lost due to the nonconservative forces.
What is the uniform acceleration kinematics equation?
dx=(vi+vf)/2*t
restorative force
force that causes a mass to return to equilibrium
What does the azimuthal quantum number represent?
l describes the subshell in which the electron resides. Each type of subshell, s, p, d, etc., has an l value.
What are common units for density?
or (A mL is equal to a cm3)
What are the units of frequency?
s-1
What is energy?
the capacity to do work or produce heat
What is the equation to calculate Gibbs Free Energy?
where G is gibbs free energy, H is the enthalpy, T is the temperature, and S is the entropy.
What is the formula for elastic potential energy?
where k is the spring constant and x is the distance from the equilibrium position
What is snell's law for the index of refraction?
where n is the index of refraction, c is the speed of light in vacuum, and v is the speed of light in the medium in question.
What is the formula for the net torque on a dipole?
where p is the dipole moment, E is the electric field, and theta is the angle between them. t=pEsin0
What is the formula for calculating dipole moment?
where q is charge of the dipole and d is the distance. p=qd
What is surface tension?
The phenomenon by which a liquid forms a thin but strong layer at its surface. This is caused by cohesion. Increase IMF-Increase surface tension
Describe the physical and chemical properties of enantiomers?
The physical and chemical properties of enantiomers are basically equivalent, except in the case of two important exceptions. 1. Optical activity 2. Reactions in chiral (biological and natural) environments. For example, a lot of enantiomers of normal molecules like glucose and proteins can be toxic to humans.
What is the triple point?
The point on the phase diagram where the gas, liquid, and solid phases are in equilibrium.
What is a dot product?
The product of the magnitudes of two vectors and the cosine of the angle between them.
What does an Ohmeter measure?
The resistance of a circuit element.
What is a solute?
The solute is the compound you add to the solvent. In this example, the blue powder is the solute because it was a solid before mixing and in the liquid phase with water after.
dB manipulation
The sound level increase by a factor of 10 every time you change the dB by 10. I changes exponentially, but dB is addition
What is a source charge?
The source charge is the charge creating the electric field of interest.
Which is the fourth quantum number?
The spin quantum number, ms
What is thermal expansion?
The tendency of objects to increase in size with increases in temperature.
What is half life?
The time it takes for half of a sample of radioactive particles to decay.
What is heat? - Chemistry
The transfer of energy between two things by virtue of their temperature difference.
What determines the buoyant force an object feels?
The volume and density of the liquid that has been displaced. That's it. The buoyant force has nothing to do with the object being placed in the fluid. A bowling ball and a styrofoam ball with the same volume as the bowling ball will experience the same buoyant force despite having different masses.
What are the general characteristics of metalloids?
There are no general characteristics of metalloids. Each metalloid is distinct from the other with a combination of both metal and nonmetal characteristics.
How do catalysts affect reactions?
They lower the activation energy.
Bonding orbitals are {{c1::lower::higher or lower energy?}} than antibonding orbitals
This also means they are more stable!
Describe the Hill Criterion of Strength
This criterion says the higher the correlation between an independent variable and a dependent variable, the more likely that they are causally related.
Describe the Hill Criterion of Temporality
This criterion states that for an independent variable to be causing a depedent variable, it must occur before the dependent variable in the study.
In an electrolytic cell, the cathode is {{c1::negative::positive or negative?}}
This makes sense because the cathode is where the electrons are going to do reduction. If the cathode is already negative, electrons don't want to go there. This means you have to put energy in to make it happen, like an electrolytic cell.
In a galvanic (voltaic) cell, the cathode is {{c1::positive::positive or negative?}}
This makes sense because the cathode is where the electrons are going to do reduction. If the cathode is positive, electrons want to go there. This means the cell will release energy from the favorable reaction, like a galvanic cell.
What is threshold frequency?
Threshold frequency is the minimum frequency (and therefore energy) of light required to knock electrons off of a given metal atom. Different metals will have different threshold frequencies.
Which variable links the horizontal and vertical aspects of projectile motion?
Time. Once the ball hits the ground, the motion stops, both horizontal and vertical. Therefore, time is the one variable that you can solve for in one dimension and then use in another. This fact will often provide the necessary variables for solving certain kinematics problems.
How does one assign directionality to torques?
Torque that generates clockwise rotation is negative. Torque that generates counterclockwise rotation is positive.
What kind of molecular orbitals go into triple bonds?
Triple bonds are made of 1 sigma bond with 2 pi bonds surrounding it. The 2 pi bonds will be perpendicular to one another.
What is turbulent flow?
Turbulent flow is rough and disorderly flow that causes the formation of eddies, which are swirls of fluid. This type of flow dissipates energy.
What is an inverse relationship?
Two variables are in an inverse relationship when an increase in one of the variables is associated with a proportional decrease in the other.
What is a direct relationship?
Two variables are in direct relationship when increasing one variable proportionately increases the other. Or, when decreasing one variable proportionately decreases the other.
Fundamentally, how is UV-vis spectroscopy useful?
UV-vis is useful for identifying compounds with interesting electronic properties, which is basically just double bonds, triple bonds, and conjugated systems.
Voltage, Current, Resistance
V - V I - C/second (Amps) R - ohms
What is VSEPR Theory?
VSEPR Theory is a system by which we can predict the shape of a molecule based on the arrangement of bonding and non bonding electrons as seen in its lewis structure.
What kinds of compounds can Gas Chromatography analyze?
Volatile compounds, which are compounds with low boiling point liquids or sublimable solids.
What is wave number?
Wave number is an analog of frequency that is used to describe the energy level of light in IR spectroscopy. Wave number is equal to 1/wavelength. The higher the wavenumber, the higher the frequency, and the higher the energy.
What is a wavelength?
Wavelength is the distance from one feature of the wave to the next instance of that feature. For example, if one is measuring the wavelength using a crest, then the wavelength would be the distance between the first crest and the second crest.
What happens when a fraction is raised to an exponent?
When a fraction is raised to an exponent, the exponent is distributed to both the numerator and the denominator.
What is nuclear fission?
When a large nucleus splits into smaller nuclei.
Whenever a log doesn't have a base written, what base do we assume it has?
When a log doesn't have a written base, we assume it is base 10 AKA, the common log.
What happens when a number is raised to a fractional exponent?
When a number is raised to a fraction, the numerator of the fraction becomes the exponent and the denominator of the fraction becomes the root.
What happens when a number is raised to a negative exponent?
When a number is raised to a negative exponent, it means that the reciprocal is being raised to the positive exponent.
What happens when a number with an exponent is raised to an exponent?
When a number with an exponent is raised to an exponent, the exponents multiply.
When do we give heat positive or negative values?
When heat is entering or leaving the system, respectively.
When will an object sink or float in a fluid?
When its density is higher or lower than the fluid, respectively.
Explain the photoelectric effect
When light of sufficiently high energy strikes a metal it knocks the electrons off the metal and thereby produces a current.
When does light refract towards the normal?
When light passes from a low index of refraction to a higher index of refraction.
Work in an Electric Field
When no friction is present: W=qV or KE=qV
What happens when numbers with exponents divide?
When numbers with exponents divide, the exponents subtract.
How do reactions respond to changes in pressure and volume, as described by Le Chatelier's principle? Note, these changes are only seen in gas systems.
When pressure is added to a gas system in equilibrium, the reaction will push the reaction to the side of the reaction with less moles of gas, and therefore less pressure. The opposite is true. When a system contracts and the volume goes down, the pressure goes up, and again, the reaction will push the reaction to the side of the reaction with less moles of gas, and therefore less pressure. The opposite is true.
What is nuclear fusion?
When small nuclei combine to form a larger nucleus.
When does light undergo total internal reflection?
When the angle of incident light exceeds the critical angle. (angle>oc)
What is happening when an atom is demoted to ground state.
When the electron spontaneously falls from a higher energy level to a lower energy level (THIS WILL ALWAYS HAPPEN) the atom loses some energy. This energy is lost in the form of a photon which the atom basically spits out.
When does laminar flow convert to turbulent flow?
When the fluid's critical speed has been exceeded.
How do waves behave when fixed at one end?
When there is a boundary of some sort on one side of the wave, the wave will hit the boundary and then reflect its direction and invert its orientation.
What is the Doppler effect?
When two objects are moving in relation to one another, the frequencies of the sounds they make will be altered.
Describe Ohm's Law.
Whenever you pass through a resistor, you lose energy in the form of a drop in electric potential. Ohm's law calculates the amount of potential you lose when you pass through a resistor.
How does one calculate capacitance due to physical properties of the capacitor?
Where A is the cross sectional area of the capacitor plates and d is the distance between them.
How does one relate mass and weight?
Where Fg is the force of weight (gravity), m is mass, and g is acceleration due to gravity.
How do you calculate the Delta G of a reaction at non standard conditions?
Where Q is the reaction quotient of the reaction, T is the temperature of the reaction, and R is the ideal gas constant.
What are the formulas for voltage?
Where Vb is the potential at point b, Va is the potential at point a, Wab is the work required to move a charge from point a to point b, and q is the charge of the moved particle. V=E/d or V=IR
How does one calculate power in terms of work?
Where W is work, t is time, and E is total mechanical energy. W=E/time E= dPE/KE/Fdcoso
How do you relate the standard potential of a reaction to its equilibrium?
Where n is the number of moles of electrons exchanging in the reaction. F is the Faraday Constant, R is the ideal gas constant, T is the temperature, and Keq is the equilibrium constant of the reaction.
Where should one assign the zero point when calculating gravitational potential energy?
Wherever is most convenient. We can pick a zero point wherever we want. Try to pick a zero point that eliminates variables.
What are some common diamagnetic materials?
Wood, plastics, water, glass, and skin
What is the difference between work function and ionization energy?
Work Function is the energy required to knock an electron off the surface of a metal, where as ionization energy is the energy to remove a bound electron from a gaseous atom/molecule.
What is the formula to calculate efficiency?
Woutput/Winput
Is electrostatic force a vector?
Yes
Is the electric field a vector?
Yes
What is the law of constant composition?
all samples of a given compound have the same proportions of their constituent elements
What kind of bonds make up a triple bond?
A sigma bond, and 2 pi bonds perpendicular to the axis of the sigma bond and each other.
What is a spectator ion?
A spectator ion is an ion that stays in the aqueous form and keeps its oxidation number after the reaction is complete. In other words, spectator ions don't change during the reaction, they are just spectating.
What is the shape of the s orbital?
A sphere
What is a free body diagram?
A visual accounting of all the forces on an object.
What is the difference between ammonia and ammonium?
Ammonia is the deprotonated basic form, NH3. Ammonium is the protonated acidic form, NH4
What is an MRI?
An MRI is just applying NMR to humans. Using NMR, we can determine the density of hydrogens in the body, which correspond to tissue types. Specifically, a dark spot on NMR tends to correspond to water where as a light spot on MRI indicates the presence of fatty tissue (lots of hydrogens). By looking at the general shape of tissues and cavities in the body, we can determine abnormalities.
What is an Amide?
An amide is a carbonyl carbon bonded to a nitrogen.
What is an electrode?
An electrode is the general name for the materials that make up the cathode and anode.
What does an exponential graph look like?
An exponential graph rises ever increasingly faster, getting steeper and steeper in a certain direction.
What does it mean for an image to be virtual?
An image is virtual if the light appears to be coming from the position of the image, but the light rays don't actually converge there.
What is an insulator?
An insulator is any material that will not easily distribute a charge over its surface. Most nonmetals are insulators.
What is an isomer?
An isomer is a molecule with a different structure but the same molecular formula as another.
Light
Appears the opposite color it absorbed
What is the loop rule?
Around a closed circuit loop, the sum of voltage sources will always be equal to the sum of voltage drops.
What is the periodic trend for atomic radius?
Atomic radius increases as you go left and down.
Where are metalloids on the periodic table?
Between the metals and nonmetals.
Center of mass and Gravity
Center of Mass depends on the center point where all the mass is concentrated and does not have to be in the object. The center of gravity takes into consideration the effect of gravity
Of the three main types of cyclohexane conformations, which is most stable?
Chair
What is Charles's Law?
Charles's law states that the volume and temperature of a gas are proportional.
What is chirality?
Chirality is a word for handedness. What handedness means is that two objects are mirror images of one another, but due to the nature of their structure it is impossible to super-impose one on to the other. This is most easily seen in our hands. Hands are mirror images, but we can't super impose them.
What is it called when a gas goes to a liquid?
Condensation
What are conservative forces?
Conservative forces are forces that do not dissipate energy e.g Gravity and Electrostatics
constructive vs destructive interference
Constructive Interference - waves add together Destructive Interference - when waves are half a wavelength, 180 degress, or pi
What is meant by converging and diverging in the context of optics?
Converging and diverging are whenthe optical device (mirror or lens) makes the real light rays come closer together or further apart, respectively, after they reflect/refract.
What are the units of charge?
Coulombs C
Should you place an ammeter in series or parallel?
Current is equivalent across elements in series and split across elements in parallel. Therefore, you should place the ammeter in series so that you're measuring the actual current. If you place an ammeter in parallel, it will split the current and the value you measure will be lower than the actual current.
What is the unit of sound?
Decible dB
How does E/Z nomenclature work?
E/Z is supposed to be used on molecules that have an immovable bond with more than one substituent on both sides, but it is basically just interchangeable with cis- trans- isomerism. First one must assign priorities to the groups on both sides of the bond. If the high priority groups are on the same side of the bond, it is given Z configuration (Zame side). If the high priority groups are on opposite sides of the bond, it is given E confiugration (Epposite side).
Describe electric potential?
Electric potential is a measure of how rich the potential for electric potential energy is at a certain distance from a charge. At areas of high electric potential, charged particles will have high electric potential energies. At areas of low electric potential, those same charged particles will have low electric potential energies.
What are enantiomers?
Enantiomers are nonsuperimposable mirror images of one another. Your left and right hand would be examples of enantiomers
What does the 2nd law of thermodynamics state, in basic terms?
Energy will always spontaneously spread out if it is not actively being kept from doing so.
Describe the formation of cyanohydrins.
First, hydrogen cyanide dissociates into its constituent ions. Then the nitrogen electrons attack the carbonyl carbon. The double bond electrons are pushed up to the oxygen which then protonates, forming a cyanohydrin.
What are flagpole interactions?
Flagpole interactions refer to a specific type of steric strain that is exhibited by axial molecules on a ring. This is why it is more stable to place large groups in equatorial positions. You avoid this strain.
What does it mean to be a fluid?
Fluids are things (gases and liquids) that can flow and conform to the shapes of their containers.
What is frequency?
Frequency is the number of full oscillations a wave completes in one second.
What are geminal diols?
Geminal diols are diols with two hydroxyl groups on the same carbon.
Where are the Noble Gases on the periodic table?
Group 18.
What are hydroxyquinones?
Hydroxyquinones are quinones with one or more hydroxyl groups.
Fundamentally, how is IR spectroscopy useful?
IR spectroscopy is useful for figuring out the types of bonds (-NH, C=O, -OH, etc.) in a sample.
How does one approach torque problems?
Identify all counterclockwise and clockwise torques and then identify all forces.
In what direction will the reaction proceed if Q = K
If Q = K then the reaction is at equilibrium. The delta G is equal to 0 and the reaction will stay where it is.
In what direction will the reaction proceed if Q > K?
If Q > K then the ratio of products to reactants is higher then it would be at equilibrium. Therefore, we'd expect the reaction to go in the reverse direction to reach the equilibrium ratio.
Describe Gas Chromatography
In Gas Chromatography, also known as Vapor Phase Chromatography (VPC) is similar to all the other chromatographic methods. The only big difference is that the eluent is a gas (usually helium or nitrogen) instead of a liquid. The stationary phase is composed of crushed metals or polymers in a 30 foot coiled tube. The column is in a temperature regulated oven to keep the sample in the gas phase as it travels through the column.
Describe nucleophilic acyl substitution reactions?
In nucleophilic acyl substitutions, a nucleophile attacks a carbonyl and then the carbonyl reforms, knocking off a leaving group. This is very similar to nucleophilic addition on aldehydes and ketones, but the carbonyl comes back instead of becoming a hydroxyl group.
What does it mean for two waves to be in phase?
In phase waves have a phase difference of 0 degrees, and are therefore lined up exactly (in phase). Below is a picture of two red waves that are in phase. The blue wave shows the superposition wave sum.
What are intermolecular forces?
Intermolecular forces are weak electrostatic forces that molecules will exhibit between one another. These Intermolecular forces are very important in determing physical properties of the molecule, such as melting points, boiling points, and density.
What kind of molecular orbitals contribute to a single bond?
Just sigma bonds.
In what way can the metallic bond be described?
Like a sea of electrons floating over a rigid lattice of metal cations. This flowing nature of the electrons over metals is what makes metals such good conductors of electricity.
What does a linear graph look like?
Like a straight line
What is mean?
Mean, aka average, is the value of all the data added up divided by the total number of data points.
As intermolecular forces in a molecule become stronger, how do melting and boiling points change?
Melting and boiling are both examples of separating atoms from one another. Atoms are held together by intermolecular forces. Therefore, as intermolecular forces get higher, boiling and melting points get higher. This is because you need more temperature energy to overcome the intermolecular forces and break the atoms up into liquid or gas form.
What are the units of Electric Field?
N/C
Do capacitors store charge?
NO! Everyone will tell you yes, but they are wrong. Capacitors store energy in the form of an electric field, not charge. It is true that charge will accumulate on the plates of capacitors, but this is an equilibrium with the rest of the circuit and for every charge that enters one side of the capacitor, a charge will leave the other side of the capacitor. Q= amount of charge on each plate
Units of Force
Newtons Remember F=ma
What is one hertz equal to?
One cycle per second 1Hz = 1/s
What is oxidation?
Oxidation is the loss of electrons. MNEMONIC: LEO the lion goes GER. Lose Electrons Oxidized. Gain Electrons Reduced.
How are mole fraction of a gas and partial pressure related?
Partial pressure of a gas will be equal to its mole fraction times the total pressure of the gas. Where PA is the partial pressure of A, XA is the mole fraction of A, and PT is the total pressure.
What are the rules of peak splitting?
Peak splitting follows the n+1 rule, where the number of adjacent hydrogens, n, + 1 equals the number of peaks after splitting.
What is plane polarized light?
Plane polarized light is light in which all of the electric field vectors are lined up in one plane.
What side of the reaction is heat on in an endothermic reaction?
Reactants side
Which type of image can be projected onto a screen?
Real images
What is refraction?
Refraction is the bending of light as it passes from one medium to another and changes speed.
How do resonance structures affect the formal charges on atoms in a molecule?
Remember that the real molecule is a hybridization of its resonance structures. So for example, if there are two resonance structures of equal stability and one in one of them the formal charge on an atom is -1 and in the other the formal charge is 0, then the overall formal charge will be the average, -1 + 0 / 2 = -1/2
What is the critical angle?
Remember that when light travels from a high index of refraction to a low index of refraction, it bends away from the normal. If you shine light with the right angle, you can actually bend light in such a way that it's angle of refraction is equal to 90 degrees, which means the light just travels along the boundary of the materials instead of refracting from one to the other. The incident angle required to make the light bend in this way is called the critical angle.
What kind of bonds make up a single bond?
Sigma bond
What is solubility?
Solubility is the maximum amount of a substance that can be dissolved in a particular solvent at a particular temperature.
What is sound?
Sound is a longitudinal wave that transmits through the oscillation of particles in a deformable medium. As such, sound can travel through solids, liquids, and gases.
What is steric strain?
Steric Strain, also referred to as steric hindrance, refers to the strain inherent in all substituents. Remember, every atom is carrying electron density, and so by definition the more spread out the electrons (and the atoms) the less strain in the molecule.
How does one calculate the work done by a gas using a P-V graph?
Take the area within the curve
How does one calculate the average velocity of an object?
Take the change in (displacement) and divide it by the change in time.
What happens to the E cell of a battery as the redox reaction powering it progresses?
The E cell changes based on how far the battery is into the reaction.
What is the FINER method?
The FINER method is a way of determining whether or not a particular scientific enterprise is worthwhile. 1. F - Is the necessary research going to be Feasible? 2. I - Do other scientists and the world at large find this question Interesting? 3. N - Is this question Novel or has it already been asked and researched? 4. E - Is this study going to be Ethical? 5. R - Is this study contributing anything Relevant to the world or is it just some pet project?
What is the fischer esterification?
The Fischer esterification is a reaction in which carboxylic acids are activated by acid and reacted with alcohols to produce esters. This mechanism follows the normal nucleophilic acyl substitution mechanism.
What are the reactants and products of the Gabriel Synthesis?
The Gabriel Synthesis uses a cyclic molcecule called Phthalamide (usually as potassium phthalimide) and Diethyl Bromomalonate in the presence of base to generate a highly substituted carb-anion intermediate. This is mixed with an R-Br (any good leaving group of choice) and treated with acid to make an amino acid.
What is the Heisenberg Uncertainty Principle
The Heisenbergy Uncertainty Principle states that it is impossible to determine the momentum and position of an electron simultaneously. This is because focusing on the momentum of the electron makes it harder to know the position, and vice versa.
What is the Nernst Equation?
The Nernst Equation allows us to determine the E cell of a battery at non standard conditions.
What is the actual yield?
The actual yield is the amount of product an individual actually obtained after completing the reaction. This amount will always be lower than the theoretical yield due to errors/side reactions/loss of products/incomplete collection of product, etc.
What is bond length?
The average distance between the two nuclei of atoms in a bond.
What is the Collision Theory of Chemical Kinetics?
The collision theory states that, for a reaction to occur, the molecules must collide with eachother in appropriate configurations. Therefore, the rate of a reaction is proportional to the number of collisions per second between the reacting molecules.
What is the SI unit of charge?
The coulomb C
What is kinetic energy?
The energy an object has by virtue of its movement. m is mass v is speed
What quantity will be equivalent before and after a dilution?
The moles of substance present.
In optics, all angles are measured from what line?
The normal line
How must a nucleophile and a leaving group be related for an Sn2 reaction to proceed?
The nucleophile has to have a stronger affinity for the electrophile than the leaving group, otherwise the leaving group won't leave and the nucleophile won't be able to attack.
How can we calculate the standard entropy of a reaction?
The standard entropy of a reaction will be equal to the sum of the standard entropies of the products minus the sum of the standard entropies of the reactants.
How does one calculate the equivalent resistance of resistors in parallel?
The sum of the inverses of the resistances will be equal to the inverse of the total resistance.
What are the axes of an IR spectra?
Transmittance versus wave number.
Where are nonmetals found on the periodic table?
Upper right side.
What are vicinal diols?
Vicinal diols are diols with the hydroxyl groups on adjacent carbons.
What is voltage?
Voltage is the difference in the electric potential between two points.
How do we convert a first order reaction into a straight line?
We graph the ln of the concentration instead of the concentration. The slope will be equal to negative 1 times the rate constant of the reaction.
When does light refract away from the normal?
When the light passes from a higher index of refraction to a lower index of refraction. NOTE: Air has a lower index of refraction than water.
How does one calculate the work done by gases?
Where P is pressure and V is volume. W=PdV - when gaves are isobaric W=0 when gases are isochoric.
How does one calculate the velocity of a wave?
Where f is frequency and lambda is wavelength.
How does one calculate the Doppler effect?
Where f is the original frequency v is the speed of sound vd is the speed of the detector vs is the speed of the source. MNEMONIC Use the TOP sign when the detector/source is moving TOWARDS the other object. Use the bottom sign when it is going away.
How do you calculate osmotic pressure?
Where pi is osmotic pressure, i is the number of ions into which the solute dissolves, M is the molarity, R is the ideal gas constant (8.314atm-L/mol-k), and T is the temperature.
What is the formula for static friction?
Where us is the coefficient of static friction and N is the magnititude of the normal force.
What are the 2 process functions?
Work Heat
Acceleration
a. NOTE: when it says constant speed - a=0 b. EX: when you throw a ball up, its acceleration is not 0 - because it falls down c. Note change direction causes deacceleration
What are the four principal quantum numbers
four quantum numbers: the principal quantum number (n) the orbital angular momentum quantum number (l) the magnetic quantum number (ml) the electron spin quantum number (ms)
Angular velocity
rate of change of angular displacement v=wr s=or
What is the standard enthalpy of formation of something already in a standard state?
0!
How are alkynes named?
1. Alkyne substituents are interesting. You actually modify the parent name still, changing the -ane into -yne, but then you let the highest order functional group partially overwrite it. 2. Alkyne parent chains replace the -ane of the parent name with the carbon#-yne.
What are the five kinds of radioactive decay?
1. Alpha Decay 2. Beta minus Decay (e- released) 3. Beta plus (positron) Decay - release a proton 4. Gamma Decay 5. Electron Capture
What are the different types of research error?
1. Bias 2. Confounding 3. Random error
What are the various forms of isomers?
1. Constitutional Isomers 2. Stereoisomers a. Conformational Isomers b. Configurational isomers I. geometric II. optical i. enantiomers ii. diastereomers
What are the two types of chemical bond?
1. Ionic Bonding 2. Covalent Bonding
What are the 4 ways to express concentration?
1. Percent composition by mass 2. Molarity 3. Molality 4. Normality
What is the NMR shift associated with carboxylic acid protons?
10.5 to 12 ppm
What is the density of water?
1000 kg/m^3
What is 15^2?
225
What is a Type 2 error?
A Type 2 error is when you report no difference exists between two things, when it does actually exist. AKA the False Negative.
What is a carbaldehyde?
A carbaldehyde is the suffix given to an aldehyde on a ring system
What is a carbonyl group?
A carbonyl group is a carbon double bonded to an oxygen.
What is a closed system?
A closed system is one in which energy can be exchanged, but matter cannot.
What is a control in an experiment?
A control or standard is a method of verifying results. By comparing to the control, we can determine if something actually changed or not.
What is a mixture?
A mixture is some combination of two things, whether or not it is homogenous or heterogenous.
What is a net ionic equation?
A net ionic equation is the complete ionic equation minus the spectator ions.
What is a phenol?
A phenol is an aromatic ring with an alcohol. Their characteristic property is that their alcohol hydrogen is way more acidic than normal alcohol hydrogens. This is because the negative charge of the conjugate base can stabilize itself in the aromatic ring.
What are the possible values for n?
Any positive integer to infinity (whole number other than 0).
In a reaction with two possible products, how do you get the thermodynamic product?
Apply a higher temperature to the reaction.
What is the EMF or Ecell?
EMF or Ecell is the combined potential difference across the anode and the cathode of the cell. This is calculated by adding up the reduction potential of whatever is getting reduced (cathode) and the oxidation potential of whatever is getting oxidized (anode).
How do we experimentally determine the rate constant and the orders of a reaction?
With experimentally determined data! This will almost always be given to you in the form of a chart.
Do real gases follow the ideal gas law?
Yes, but not at all ranges. Real gases do not follow the ideal gas law at high pressures, low volumes, and low temperatures.
How does one calculate the power of a lens?
where f is the focal length in meters.
What is the mass of a proton?
1 amu
How do you assign R and S to chiral centers?
1. Assign priority to all groups using Cahn-Ingold-Prelog 2. Rotate the molecule in 3D space such that the lowest priority group (4) is going into the page (dashed). IIf the (4) group is already on dash, you don't have to do anything! 3. Draw a circle starting from the highest priority group (1) going through (2) and (3). 4. If you drew the circle clockwise, the molecule has R configuration. If you drew the circle counterclockwise, the molecule has S configuration. This method is super effective and very fast, but it can be very hard with more complicated molecules. In those cases, it is sometimes better to represent the chiral carbon as a fischer projection and determine absolute configuration from there.
How do we use Huckel's rule to determine if a compound is aromatic?
1. Compound must be cyclic, not linear. 2. Compound must be planar so that the p orbitals line up. 3. The molecule must have a continuous ring of p orbitals with no sp3 carbons interrupting 4. The molecule must have 4n+2 electrons in the p orbitals where n is any whole number. (2, 6, 10, etc. not 4, 8, or 12.)
What are the 4 things that can affect the rate of a reaction?
1. Concentration of reactants 2. Temperature 3. The medium (solvent) in which the reaction takes place 4. Catalysts
What are the 4 types of potential energies?
1. Gravitational 2. Elastic 3. Chemical 4. Electrical
What are the steps for approaching a rate law chart?
1. Identify pairs of trials where one reactant is being varied while the others change. 2. Using one of the pairs of trials, see how the rate changed and compare that to how the reactant changed. 3. The relationship between these changes will give you the rate order according to the equation Xy=Z where X is the ratio of the concentrations, y is the order, and Z is the ratio of the rates. So for example, if you chose a trial where one of the reactants doubled (2x) but the rate quadrupled (4x) you would have 2y=4. And so the order would be 2
How does one name an organic molecule?
1. Identify the longest carbon chain containing the highest-order functional group. The number of carbons and the type of functional group will determine the parent name of the molecule. 2. Number the chain starting from the highest priority functional group. If the functional groups have the same priority, numbering the chain should make the numbers of any branches in the chain lowest. 3. Name the Substituents and place the names before the parent name. If there is more than one substituent of the same type, indicate it with the prefixes di, tri, etc. If there is more than one substituent of different types, place them alphabetically. 4. Assign numbers to each substituent. 5. Complete the name.
What are the 4 types of thermodynamic processes?
1. Isothermal 2. Adiabatic 3. Isobaric 4. Isovolumetric
List the 7 types of electromagnetic radiation represented in the electromagnetic spectrum from lowest energy to highest energy.
1. Radio Waves 2. Microwaves 3. Infrared Waves 4. Visible Waves 5. UV rays 6. X-Rays 7. Gamma Rays
What are the four fundamental forces?
1. Strong Nuclear Force 2. Weak Nuclear Force 3. Gravitational Force 4. Electromagnetic Force
What are the 4 units in which pressure is measured?
101.3 kPascals, 760 mmHg, 760 torr, 1 atm
What are the ideal bond angles for a carbon with four bonds (sp3)?
109.5 degrees
What is the value of acceleration due to gravity?
10m/s2
What are the ideal bond angles for a carbon with 3 bonds (sp2)?
120 degrees
What is 11^2?
121
What is 12^2?
144
What is 14^2?
196
How many electrons can any given orbital hold?
2
What is the NMR shift associated with alkyne protons?
2 to 3 ppm.
How much volume does one mole of an ideal gas take up at STP?
22.4 Liters
What is the shape of the P orbital?
3 lobes that share a center but extend across three different axes.
What is the speed of light in air equal to?
3.00*108 m/s
What is the NMR shift associated with aromatic protons?
6 to 8.5 ppm
What is Planck's constant equal to?
6.626*10-34 J*s
What is a phase diagram?
A Phase diagram is a graph that shows the different phases of something at varying pressures and temperatures.
What is a Type 1 error?
A Type 1 error is when you report a difference exists between two things, when it doesn't actually exist. AKA the False Positive.
What is a backside attack?
A backside attack is the way nucleophiles attack electrophiles in Sn2 reactions. They always attack this way because it is lower energy than attacking from the front (where there is more stuff in the way). Backside attacks are interesting in that they invert the configuration of the molecule when they occur. What happens to a molecule during a backside attack is similar to what happens to an umbrella when the wind blows it inside out.
What is a barometer?
A barometer is a device that measures the pressure of something.
What is an example of a constant volume calorimeter?
A bomb calorimeter is a contstant volume calorimeter. The vessel is rigid and its volume does not change during the chemical reactiion.
What is a cathode?
A cathode is where reduction occurs.
What does it mean for protons to be chemically equivalent?
A chemically equivalent proton is a proton that is attached to the same atom and surrounded by the same atoms. The NMR can't really tell the difference between chemically equivalent protons, and so they will have the same chemical shift value. However, the more protons, the higher the absorbance (height of the peak) at that chemical shift.
What is a closed boundary?
A closed boundary is a boundary that does not allow oscillation, and therefore corresponds to a node. A string tied to a brick wall would be a good example of a wave with a closed boundary.
What is a complete ionic equation?
A complete ionic equation shows a reaction with all of the soluble reactants and products written as their dissociated ions.
What is a condensation reaction?
A condensation reaction is a reaction where two molecules are joined with the loss of a small molecule.
What is a configurational isomer?
A configurational isomer is a molecule that differs in its 3D orientation in such a way that it can't just rotate around the bond to interconvert, like a conformational isomer. This is seen in double bonds and stereocenters.
What is a conformational isomer?
A conformational isomer is a type of stereoisomer that is a result of the free rotation around single bonds. At any point, a single bond might rotate into a different conformation and become a stereoisomer from another similar molecule with a different rotational conformation.
What is a cross product?
A cross product is the product of the magnitude of two vectors and the sin of the angle between them.
What is a cross-sectional study?
A cross-sectional study looks at many different populations at a specific time point to observe the differences in certain outcomes between them.
what is a -dioic acid?
A dioic acid is a molecule with carboxylic acid groups on both ends of the molecule. They are named by adding -dioic adic to the parent name.
What is the archetypal form of a double-displacement reaction?
A double-displacement reaction is when elements from two different compounds swap places with each other to form new compounds.
What is viscosity?
A fluid's resistace to flow. Thick fluids have high viscosity, thin fluids have low viscosity.
What is a galvanic (voltaic) cell?
A galvanic (or voltaic!) cell is an electrochemical cell in which electrons are going from low reduction potential to high (anode to cathode), and releasing energy.
What is a group in regards to the periodic table?
A group is a vertical column on the periodic table.
What is a heating curve?
A heating curve is a graph of temperature versus heat added.
What is a heterogenous catalyst?
A heterogenous catalyst is a catalyst that is in a different phase (solid, liquid, gas) than the reactants.
What is a homogenous catalyst?
A homogenous catalyst is a catalyst that is in the same phase (gas, liquid, solid) as the reactants.
What is a mesylate?
A mesylate is a compound containing the functional group -SO3CH3. Mesylates are good leaving groups. Mesylates are prepared by using methylsulfonyl chloride on an alcohol in the presence of a base.
What is a mole?
A mole is a unit we made to conveniently describe the quantity of chemical quantities. One mole is equal to 6.02*10^23 of whatever substance is in question. You could have a mole of cats in the same way you have a dozen eggs. One mole of cat is 6.02*10^23 cats and one dozen of eggs is 12 eggs.
What is a molecular orbital?
A molecular orbital is like an atomic orbital (the area of space where electrons can be found) but for a molecule instead of an atom. Areas of overlap between the atomic orbitals that make up the molecular orbital correspond to bonds in the molecule.
What is a negative control?
A negative control is used to ensure no change in the dependent variable when no change is expected. For example, you might give a new HIV test to people you know don't have HIV to make sure it doesn't mis-diagnose them.
What is a nonpolar covalent bond?
A nonpolar bond is a covalent bond between atoms of identical or nearly identical electronegativities that share electrons equally. This is type of bond is most often manifested by the diatomic molecules.
What is a nucleophile?
A nucleophile is an atom that is attracted to the positive charge of the protons in the nucleus of other atoms. Generally nucleophiles have lone pairs or pi bond electrons that can attack electrophiles.
What is a photon?
A photon is a massless wave-like and particle-like packet of electromagnetic (light) energy.
Explain why plane mirrors always make virtual images.
A plane mirror is defined as a flat reflective surface. That means that the light rays will always just bounce off of the mirror with the same angle they bounced onto it with. This means that the light rays don't ever converge, they just get reflected away. Any light we see is just being bounced off the mirror, but our brains are used to tracing light back to its source, so what will happen is instead of really seeing the reflection, our brain treats the reflected rays as if they came from an imaginary source and traces them back to said source. This is why when we look into a mirror, it's like there is a person looking back at us from the other side of the mirror. Our brain thinks that is where the light is coming from. Because the light is actually converging on our side of the mirror, and not where we perceive the image to be, this is a virtual image. Focal length is infinity and di=do
What is a population?
A population is the entire set of individuals with a certain set of characteristics.
What is a scalar?
A quantity with a magnitude only
What is a sample?
A sample is a subset of a population that is used to estimate population data.
What does it mean to be a saturated solution?
A saturated solution is a solution that has the maximum amount of dissolved ions as defined by the ksp. Any solute added to a saturated solution will precipitate.
What is a sigma bond?
A sigma bond is a molecular orbital formed by the head-to-head or tail-to-tail overlap of two atomic orbitals. note: sigma bonds can bet between atomic orbitals of any type, not just s orbitals.
What is the archetypal form of a single-displacement reaction?
A single-displacement reaction is when an atom or ion in a compound is replaced by an atom or ion of another element.
What is a solution?
A solution is a homogeneous mixture of two or more substances in a single phase (usually liquid).
How do we know if something is not a spectator ion?
A species is defined as a non-spectator when it's oxidation number or it's physical state (gas, solid, liquid, etc.) changes.
What is a standing wave?
A standing wave is a wave that appears to be stationary because of the interference pattern of the two waves that make it. The only apparent movement of a standing wave will be the fluctuation of the amplitude of the wave. Standing waves can only be observed in closed end wave systems. The gif below illustrates. The top wave is the incident wave, the middle wave shows the reflected wave, and the bottom wave shows the superposition wave of the top and middle wave.
What is a state function?
A state function is a thermodynamic property that is a function of only the current equilibrium state, not the path that was taken there.
What is a stereoisomer?
A stereoisomer is a molecule with the same chemical formula and the same connections of atoms, but in different spatial arrangements.
What is a stereospecific reaction?
A stereospecific reaction is a reaction that produces a specific stereoisomer, not a racemix mixture.
What does it mean to be an supersaturated solution?
A supersaturated solution is a solution in which the Ion product of the ions is higher than the ksp. Normally this wouldn't be possible, but with special treatment it can be achieved. First, you saturate a solution, so it's IP = ksp and adding anymore solute will cause precipitation. Then, you heat the solution, so it's ksp increases. You can now add some solute again until you reach the new ksp. Once you've added solute and reached the new ksp, you slowly cool the reaction, lowering the ksp. If you're careful, the extra solute you added will not precipitate and will instead remain suspended in solution. This means that the IP is greater than the Ksp!
What is a transverse wave?
A transverse wave oscillates perpendicular to the direction of movement of the wave.
What is a trough?
A trough is the lowest point a wave reaches.
What does a voltmeter measure?
A voltmeter measures the voltage between two points in a circuit. REMEBER: 10 mV decrease in transmembrane voltage means you put it in as a negative number into your equation. Q can be negative. I can be negative.
Describe the hydration of aldehydes and ketones.
A water molecule attacks the carbonyl carbon, popping the double bonded electrons up onto the oxygen. The oxygen then takes the extra proton from the attached water molecule, forming a geminal diol. This reaction proceeds slowly, and it can be sped up by adding a small amount of catalytic base or acid.
What does a wedge represent?
A wedge represents something coming out of the plane of the page, towards you.
Describe the graph of a zeroth order reaction?
A zeroth order reaction means the rate of the reaction is independent of the concentration of the reactants. Therefore, the rate of the reaction is constant, and the reactants will be used up over time at a constant rate. I.e. a straight line.
How are acid anyhdrides usually formed?
Acid Anhydrides are normally created from the condensation reaction of two carboxylic acids.
When will an acid-base reaction proceed spontaneously, based on the strength of the reactants and the products?
Acid base reactions only proceed spontaneously if the products are weaker in terms of acidity and basicity than the products.
What are characteristic physical properties of alcohols?
Alcohols, because of their -OH moiety, can participate in hydrogen bonding. This results in alcohols having very strong intermolecular forces, and thus higher melting and boiling points. The more -OH's, the stronger the hydrogen bonding. Alcohols are also polar, and dissolve well in water.
Describe the reduction of aldehydes and ketones?
Aldehydes and ketones, when combined with reducing agents such as LiAlH4 and NaBH4, are reduced to alcohols (less bonds to oxygen!).
Describe the formation of hemiacetals or hemiketals from aldehydes and ketones respectively?
Aldehydes treated with one equivalent of alcohol will produce hemiacetals. In this reaction, the alcohol acts as a nucleophile and attacks the electrophile carbonyl carbon. The electrons pop up to the oxygen, and the oxygen picks up the alcohol's hydrogen, resulting in a hemiacetal. This reaction can be catalyzed with acid which will protonate the carbonyl oxygen and make the carbonyl carbon a better electrophile. The formation of hemiketals from hemiacetals is exactly the same, except there will be R groups on both sides of the carbonyl carbon, not just one.
How do the penetrating powers of Alpha, Beta, and Gamma decay compare?
Alpha Particles penetrate very little, Beta Particles penetrate a modest amount, and Gamma Rays penetrate the most.
What is alpha decay?
Alpha decay is when an unstable nucleus emits an alpha particle AKA Helium Nucleus. Electrons go with protons. Mass number goes with neutrons
What are some common paramagnetic materials?
Aluminum, copper, and gold
What does it mean to be isobaric and how does that affect the first law of thermodynamics equation?
An Isobaric process is one in which there is no change in pressure. Keeping pressure constant does not affect U = Q + W
What is an alcohol?
An alcohol is a molecule with a highest priority functional group of an -OH.
What is an aldol?
An aldol is a molecule with an aldehyde and an alcohol. Note, that aldol reactions are still called aldol reactions, even when its actually a ketone and an alcohol.
What is an antibonding orbital?
An antibonding orbital is a molecular orbital where the two atomic orbitals overlapping have opposite signs and cancel out when they combine.
What is an antinode?
An antinode is any point on a standing wave where interference is maximized and the amplitude is greatest.
What is an aqueous solution?
An aqueous solution is any solution in which the solvent is water.
What is an electron configuration?
An electron configuration is a shorthand accounting of the electrons in an atom using s,p,d,f notation.
What is an enamine?
An enamine is the tautomer of Imines. It is a carbon double bond with an amino group attached.
What is an ideal gas?
An ideal gas is the hypothetical gas described in the ideal gas law. It refers to a gas that has 0 volume and 0 intermolecular forces. As the molecules in the gas get bigger and as they exhibit stronger intermolecular forces, they behave less ideally.
What is statistical significance?
An intervention's effects are statistically significant when it can be said that they do not happen due to random chance. This is usually indicated with p values of less than 0.10 or 0.05.
What is an open system?
An open system is one in which both matter and energy can be exchanged with the surroundings.
What is an orbital?
An orbital is a region of space outside of the nucleus where electrons can be found.
What is an Oxidation-Reduction (Redox) reaction?
An oxidation-reduction reaction is a reaction that involves the transfer of electrons.
What is angular frequency?
Angular Frequency is a measurement of how many radians (2pi radians is 1 full circle) a wave rotates per second. This is just another way of thinking about frequency. Although it is a little harder to visualize, thinking about frequency in this way is useful for certain situations. In the above example, the wave rotates a full circle (2 pi radians) in 2 seconds.
What is an anhydride?
Anhydrides are molecules with two carbonyls bonded to the same oxygen.
What is Pascal's Principle?
Any change in pressure in a fluid will be transmitted undiminished to every portion of the fluid and to the walls of the containing vessel. F/A=F/A
describe sp orbitals
sp - seen in molecules with 2 areas of electron density. Results from the combination of an s and a p orbital. Leaves 2 p orbitals open. These p orbitals can interact with nearby p orbitals to form pi bonds.
How does entropy always change during solvation?
Because solvation spreads molecules out, the change in entropy for this process is always positive.
Why do we need to know how to convert first order and second order graphs into line graphs?
Because we can get the slope of a line, and the slope of the line graph equals the rate constant k!
What is Beta plus decay?
Beta plus decay is when an atom emits a beta plus particle aka positron. This happens when an unstable proton turns into a neutron and a positron. The neutron stays in the nucleus and the positron is emitted as a beta plus particle. This causes the atomic number of the atom to decrease and the mass number to stay the same.
What is the purpose of blinding?
Blinding is used to strip away the expectations of both subjects and researchers so that those expectations don't interfere with the study.
What is boiling point elevation?
Boiling point elevation is the fact that, as you add nonvolatile solutes to a solution, it's boiling point increases. This is described mathematically below. Where Delta T is the change in boiling point, Kb is a constant, m is the molality of the solution, and i is equal to the number of different particles the solute dissolves into. For example, NaCl would dissolve into two ions, so i would equal 2.
What is bond dissociation energy?
Bond dissociation energy is the average energy that is required to break a particular type of bond between atoms in the gas phase. Some sample bond dissociation energies are shown below.
What is bulk modulus?
Bulk modulus is a measure of an object's resistance to compression. Bulk modulus is lowest in gases (easily compressed) and highest in liquids and solids (almost impossible to compress)
What are the equations for electric field?
where Fe is the electrostatic force on the test charge, q is the charge of the test charge, Q is the charge of the source charge, and r is the distance from the source charge. F=E*q
What is the specific heat equation?
where c is the specific heat of the substance. MNEMONIC: Q=MCAT
How do we calculate the change in entropy?
where q is the heat of the process and T is the temperature at which the process occurred.
How does one calculate resistance?
where rho is the resistivity, L is the length of the resistor, and A is its cross-sectional area.
What is the formula for calculating the magnetic field produced by current traveling through a wire?
where u is the magnetic susceptibility constant, I is the current in the wire, and r is the distance from the wire.
What is the formula for kinetic friction?
where uk is the coefficient of kinetic friction and N is the normal force.
What is the equation for the continuity equation?
where v is linear speed, A is cross sectional area of the pipe, and Q is flow rate
What are conjugated bonds?
Conjugated bonds are bonds that have free p-orbitals adjacent to one another. This is basically only possible when there are sp2 hybridized carbons adjacent to one another. Electrons can sort of hop across adjacent p orbitals. Conjugation is the foundation of resonance.
Describe the shape of a d orbital?
D-orbitals are mostly shaped like 4 leaf clovers, except for the donut dumbell version of the d orbital.
What is decarboxylation?
Decarboxylation describes the complete loss of the carboxyl group as carbon dioxide. This occurs more readily under heated conditions and with 1,3-dicarboxylic acids.
What is detection bias?
Detection bias arises when educated professionals use their knowledge in an inconsistent way by seraching for an outcome disproportionately in certain populations. HUGE PROBLEM IN MODERN RESEARCH. This is basically when you only look for samples that confirm your hypothesis.
What is effusion?
Effusion is the flow of a gas particle under pressure from one area to another through a small opening.
What do you call a reaction with a positive Gibbs Free Energy?
Endergonic
What is the first law of thermodynamics?
Energy is never created nor destroyed, only transferred from one form to another. In other words, the total energy at the beginning of a problem must equal the total energy at the end of a problem. dU=Q+W - relative of the surroundings on the system
What is potential energy?
Energy of an object by virtue of its position in a system or some other intrinsic quality.
What are esters?
Esters are compounds with a carbonyl bonded through an oxygen to another carbon.
What do you call a reaction with a negative Gibbs Free Energy?
Exergonic
What is the equation for the buoyant force?
F = density*gravity*volume
What is the SI unit for capacitance?
Farad
How does the common ion effect work?
For a soluble substance, if either of the constituent ions are present, they will appear in the products of the solvation equilibrium, and push the equilibrium left towards the precipitate, as predicted by le chatelier's principle.
What is GC-MS?
Gas Chromatograph-Mass Spectrometry refers to the fact that Mass Spectrometers are often hooked up to Gas Chromatographs so that, as the gaseous molecules elute separately, they can also immediately be analyzed in regards to their mass.
What kinds of reactants and products appear in the equilibrium expression?
Gases in all gas systems and aqueous molecules in aqueous systems. Solids and liquids (other than water) do not appear in the equilibrium expression.
What is gauge pressure?
Gauge pressure is the difference between the absolute(hydrostatic) pressure in/on something and the atmospheric pressure that the object always feels. Essentially, the gauge pressure is how much "extra" pressure is on something.
What is Gay-Lussac's Law?
Gay-Lussac's Law states that pressure is proportional to temperature.
What factors affect the speed of Sn2 reactions?
Generally, the less substituted the carbon being attack, the less steric hindrance and the more room for nucleophiles to attack. Sn2 reactions are second order, so increasing the concentration of the substrate or the nucleophile will increase the speed of the reaction as well.
What factors affect the speed of Sn1 Reactions?
Generally, the more substituted the carbocation, the more stable it is because alkyl groups donate electron density and help deal with the positive charge. By stabilizing the rate determining step, the reaction goes faster. Sn1 Reactions are first order reactions, therefore increasing the concentration of the substrate (not the nucleophile though) will also increase the speed of the reaction.
What is heat capacity?
Heat capacity is the product of the specific heat of an object and its mass. In other words, Heat capacity = m*c
What is hybridization?
Hybridization is a way of accounting for the unequal distribution of an atoms electrons within its orbitals. Essentially, an atom will mix its orbitals together based on how many bonds it has to create an overall hybridized orbital.
What is the dipole moment?
In a polar compound, the dipole moment is the net vector of electrical charge in the molecule. In diatomic molecules, this will simply be the vector from the partially positive element to the partially negative element. However, in molecules with multiple polar bonds, the multiple electrostatic vectors will have to be summed in order to get the net vector.
Describe the Gabriel Synthesis
In the Gabriel Synthesis, Phthalimide attacks DiethylBromomalonate to form a highly substituted cyclic intermediate. This intermediate is treated with a base to form a relatively stable carbocation. The carbocation attacks an organic molecule with a good leaving group using SN2 substitution. The R group you pick here will determine which amino acid ends up getting made. The new intermediate is treated with base and water to release the dioic acid part of the intermediate and break the ring. Treatment with acid and heat will decarboxylate the liberated dioic acid to form an amino acid.
What are the reactants and products of the Strecker Synthesis?
In the Strecker Syntehsis, one starts with an aldheyde, NH4Cl, and KCN. This is a technique used to synthesize amino acids.
Where are neutrons located?
In the nucleus
Where are protons located?
In the nucleus
Where are electrons located?
In the orbitals surrounding an atom's nucleus.
What is transesterification?
In transesterification, an ester is nucleophilically acyl substituted by an alcohol, which results in a different ester. This is why its called trans-esterification, because you're just changing the ester group from one to another.
What are the three exceptions to the Octet Rule?
Incomplete Octet Elements: These elements are stable with less than eight electrons in their valence shell. Hydrogen (2), Helium (2), Lithium (2), Beryllium (4), and Boron (6). Expanded Octet: Any element in period 3 and greater can hold more than eight electrons. For example, Phosphorus (10), Sulfur (12), Chlorine, (14) and others. Odd numbers of Electrons: Any molecule with an odd number of valence electrons cannot distribute those electrons to give 8 to each atom, so one of the atoms won't have a full octet in these molecules.
In which direction will a negative charge's electric field radiate?
Inward
How do we add or subtract fractions with the same denominator?
Just add/subtract the numerators.
For a forward reduction reaction with a known reduction potential, how do we find the oxidation potential of the reverse reaction?
Just flip the reaction to make it an oxidation and flip the sign on the standard potential.
How to calculate
Keep other reactants the same. See how they change: F=c^x
What is keto-enol tautomerization?
Keto-enol tautomerization is the tendency for ketones/aldehydes to enter into equilibrium with their enol isomers.
What is Le Chatelier's principle?
Le Chatelier's principle states that equilibria will always oppose changes made to themselves. So, if you shift an equilibrium in one direction, the equilibrium will naturally oppose that shift and go the other direction.
What are leaving groups?
Leaving groups are the groups that are displaced during heterolytic reactionns. Generally speaking, weak bases are stable with extra electrons, and so they make good leaving groups. (I-, Br-, and Cl-). Leaving groups can also be strengthened by inductive effects from electron withdrawing groups.
How do we represent the bonded and unbonded electrons in a molecule?
Lewis Structures
What does a parabolic graph look like?
Like a U. This reflects a squared variable, which means both positive and negative values in the independent variable lead to positive dependent variables.
How do we name anhydride substituents and parent chains?
Like all the carboxylic acid derivatives, anhydrides won't really ever be substituents, but in those rare cases that they are you can name them as alkanoyloxycarbonyl- When an anhydride is the parent, you must name both sides of the anhydride using the chain lengths and the -oic suffix. Place the names in alphabetical order and add "anhydride" to the end.
What is line angle formula?
Line angle formula is a way of simplifying the drawing of organic molecule. In this method, the angles in lines represent carbons and the hydrogens on said carbons aren't drawn.
How do you quickly determine the harmonic of an open pipe?
Look at the number of nodes
What are common electron donating groups?
Low electronegativity substituents such as alkyls are generally electron donating due to their loosely held electron density.
What are the units of wavelength?
Meters
What is the equation for linear thermal expansion?
Mnemonic: When temperature changes, the length changes ALOT
What is molality?
Molality is the ratio of the moles of solute to the kilograms of the solvent.
Fundamentally, how is NMR spectroscopy useful?
NMR spectroscopy is the most useful of the spectroscopic methods because we can use it determine the entire structure of a molecule.
How does one calculate the average acceleration over time?
NOTE: acceleration is 0 when speed is constant.
How do you name compounds with 2 double bonds?
Name both carbon numbers and give it the name diene. Similar process for tri-enes
What is the archetypal form of a Neutralization reaction?
Neutralization reactions are a specific type of double-displacement reaction in which an acid reacts with a base to produce a salt.
Is electrical potential energy a vector?
No
What does it mean to be in thermal equilibrium?
No net heat is flowing between objects in thermal contact.
Does Hess's law only apply to enthalpy?
No, Hess's law applies to any state function.
Do two objects need to be in physical contact to be in thermal contact.
No, it is possible for objects to be in thermal contact without touching one another, although, objects in thermal contact are usually in physical contact too.
Even though there is a defined difference between cis and trans and E/Z isomers, does it really matter?
No. A lot of people will just use the Cahn-Ingold-Prelog priority rules to determine E/Z with a multisubstituent molecule, but then still end up calling the molecules cis or trans. The point of this flashcard is to remind you to be flexible in the way you apply the definitions. If you see a molecule called cis-, even if it isn't technically a cis trans isomer, you still know what they are trying to say: higher priority substituent on the same side of the molecule.
Do all compounds with internal electronegativity differences have dipole moments?
No. Although most compounds with internal electronegativity differences will have internal dipoles, if the structure is symmetric, the internal dipoles will all cancel out resulting in a nonpolar compound with no dipole moment.
Can a catalyst ever make a nonspontaneous reaction spontaneous?
No. Catalysts only affect the activation energy of the reaction, not the delta G.
Can double and triple bonds freely rotate?
No. They are locked into place by pi orbitals.
Do catalysts just speed up the forward reaction? M
No. They lower the transition state energy, which makes it easier to go forward through the reaction or backward through the reaction.
How long does an atom stay in an excited state?
Not long at all. Atoms want to be in ground state because it is the most stable configuration. Even when forced into an excited state, atoms will revert back to ground state.
How do we multiply fractions?
One must simply multiply the first numerator by the second numerator and the first denominator by the second denomniator.
What are some good oxidizing agents?
Oxidizing agents get reduced themselves, and therefore will have features that make them attractive to electrons. Two main examples would be electronegativity (O2, Cl2, etc.) and high positive charge on an atom (Mn7+ in MnO4- and Cr6+ in CrO42-.
How do parallel plate capacitors work?
Parallel plate capacitors are composed of two plates, one connected to the positive terminal one connected to the negative terminal, separated by a small distance. The plate connected to the positive terminal will build up positive charge and the plate connected to the negative terminal will build up negative charge. The difference in charge between the two plates will cause an electric field to develop between them. The energy that is stored in a capacitor is stored in the electric field it creates.
How do paramagnetic materials behave when exposed to magnets?
Paramagnetic materials become weakly magnetized by and attracted to the magnet.
What is percent yield?
Percent yield is the ratio of the actual yield to the theoretical yield multiplied by 100%. In practical terms, a Percent Yield of 90% means that you obtained 90% of the absolute maximum value you could have gotten if you did everything perfectly.
What are some of the unique properties of phosphoric acid?
Phosphoric acid has 3 acidic protons with pkA's of 2.15, 7.2, and 12.3. This means that phosphate is a super good buffer because it will buffer solutions of ph: 1.15-3.15 (plus or minus one first pKa) 6.2-8.2 (plus or minus one second pKa 11.3-13.3 (plus or minus one third pKa.)
What are physical properties?
Physical properties are characteristics of processes that are associated with the physical (what it's like), not-chemical (how it reacts), properties. These are things like melting point, boiling point, solubility, density, odor, and color.
How does one calculate power in terms of force?
Power = Force * Velocity * Cos(theta)
What is reaction coordinate?
Reaction coordinate is the x-axis of coordinate diagrams. It's just a weird way of saying how far into the reaction you are. This is usually seen on thermodynamic graphs.
What is normality (N)?
Remember when you learned that sometimes 1 mole of a molecule can be made up of more than one mole of a certain atom? For example, 1 mole of H2O is made of 2 moles of H and 1 mole of O? Well, normality is a way to account for this difference in the molecule and the atoms into which it could potentially split up. Normality is like Molarity, in that it is measured in moles per liter. But, Normality is not the moles of the substance itself per liters. Instead, Normality is the moles of what we are interested in per liters. In the below example, we are interested in Hydrogen ions. Notice how 3 different compounds at the same molarity, 1M can have very different Normalities due to their differential contribution of hydrogen ions to the solution.
{{c1::sigma::sigma or pi}} bonds allow for free rotation of the atoms that make up the bond.
Remember, a pi bond is made from the overlap of electron density between two parallel pi bonds. If you try to rotate one of the atoms, you will start to disrupt the bond. The electrons prefer being in the bond to floating around randomly, so they will resist your attempt to rotate the pi bond.
What is resonance?
Resonance is a phenomenon in which electron density is spread around a molecule due to the presence of conjugated bonds. This is most often symbolized by drawing different versions of the molecule in which the double bond is in different locations, although in reality, the double bond is actually spread out across all the locations.
What is standard temperature and pressure (STP)?
STP is 0 degrees celsius (273K) and 1 atm. This is different than standard conditions! STP is used for ideal gas calculations.
What is steric protection?
Steric protection is the process of protecting a functional group of interest from further reactions by converting it into a temporary protecting group that is sterically hindered or unreactive in the following reactions.\
What types of streches and bends can molecules undergo?
Symmetric and Asymmetric bends and stretches
What is the HOMO?
The HOMO is the Highest Occupied Molecular Orbital. This is the highest energy level at which the electrons naturally sit.
Describe the second step of the aldol condensation
The aldol generated in the first step is treated with strong base and high temperatures, which generates an unsaturated alpha beta carbonyl. The aldol condensation is useful for lengthening carbon chains on carbonyl containing compounds.
What is the alternative hypothesis?
The alternative hypothesis is the hypothesis we generate as part of our reserach question. It is what we are usually trying to prove as part of our research.
What is the atomic mass of an atom?
The atomic mass of an atom is its mass number minus the mass lost in the form of binding energy. However, the mass lost to binding energy is so small that the atomic mass and the mass number are basically the same.
What is temperature proportional to and founded upon?
The average kinetic energy of the particles that make up a substance. The internal energy of the system.
What is the common ion effect?
The common ion effect states that the solubility of a solution can be affected by adding other substances.
What is the common log?
The common log is just a log with a base of 10. Generally, the 10 is omitted and it is understood that any log without a written base is a common log with a base of 10.
Describe the continuity equation?
The continuity equation states that the flow rate must be equal at all points in the pipe, regardless of changes in cross-sectional area.
What is air resistance?
The force of friction with the air. This force opposes movement and increases as speed increases, causing an object to reach a terminal velocity.
What is tan theta equal to?
The length of the opposite side of the angle over the length of the adjacent side.
What is sin theta equal to?
The length of the opposite side of the angle over the length of the hypotenuse.
What happens when the vapor pressure of a liquid is equal to external pressure on the liquid (usually 1 atm, but can change depending on where you are.)
The liquid boils!
What is the log base A of the same number, A?
The log base A of the same number A is equal to 1. This is because if you raise a number to the 1 you get that same number.
Double and triple bonds span 2 carbons, so which one do we use to name them?
The lower number one. For example, a double bond that spans carbons 2 and 3 would be named -2-ene
Which is the third quantum number?
The magnetic quantum number, ml
What is the normal force?
The normal force is a contact force that keeps objects from passing through one another. The normal force is perpendicular to the plane of contact between two surfaces.
What is period?
The number of seconds it takes a wave to complete one oscillation. Represented by a capital T.
What do groups allow us to easily ascertain?
The number of valence electron an element has.
What is the order in terms of kinetics?
The order is the number a reactant is raised to. Remember, the order of the reactant must be experimentally determined. The balanced equation will not predict the order.
What is the phase difference between waves?
The phase difference is the extent to which the waves are offset. The higher the phase difference, the more offset the wave.
What is a rate law?
The rate law is just another term for the rate equation.
What does it mean for an image to be real?
The rays of light actually converge at the position of the image.
What is the reaction quotient?
The reaction quotient, Q tells you the ratio of products to reactants at some point other than equilibrium. The reaction quotient can be compared to the Equilibrium constant for a given reaction and used to determine if the reaction is going to progress forward, backwards, or stay where it is.
What is torque?
The rotational force that occurs when a force is applied to a lever arm on a fulcrum of some length.
What is the solvent front?
The solvent front is how far the solvent was allowed to travel overall in a TLC analysis.
What is the specific heat of a substance?
The specific heat of a substance is the heat energy required to raise one gram of a substance by one degree celsius or kelvin.
What is the purpose of the right hand rule?
To determine the direction of the resultant vector of a cross product.
How do we divide fractions?
To divide fractions, we simply flip the second fraction and then multiply like normal.
What is Torsional strain?
Torsional strain is the strain associated with large molecules being lined up in space. This strain makes the molecule less stable.
What is transmittance?
Transmittance is like the opposite of absorbance. If you absorb all the light, you transmitted none of it. If you absorb none of the light, you absorbed all of it. This means that the bottom of the valleys on the IR spectra are where the most absorption is happening.
How does Ultrasound technology work?
Ultrasound machines make sound waves and apply them to the surface of the patient's body. When the sound waves travel through the body, they encounter various tissues. Whenever a sound wave passes into a new tissue, some of the wave passes through the tissue and some is reflected back to the source. Different tissues allow different amounts of wave to reflect back to the source. The more the tissue reflects back to the source, the more brightly the tissue will appear on ultrasound. Using all of this, one can visualize a 2D slice of the body. One makes note of where bright/dark areas are to determine which tissues are present and where they are present within that 2D slice. You can even target specific slices of the body by manipulating the distance at which the ultrasound is operating. Distance can be calculated because you know the speed of the wave (given) and you know how long you let the wave travel (given) so you can always calculate the distance of the tissue from which the wave is reflecting. Ultrasound relies fundamentally on the proclivity of waves to reflect when they hit borders between different media.
How do you balance a redox reaction?
Using the half-reaction method.
Generally speaking, which layer will be on top and which layer will be on the bottom in a separatory funnel?
Usually the top layer in a separatory funnel will be the organic layer, but ultimately which layer sinks and which one floats is determined by their relative densities.
What is Vacuum filtration?
Vacuum filtration is when the liquid and solid are put under vacuum to suck them through the filter. This is the preferred method when you are more concerned with pure residue, because even though the vacuum might accidentally pull some residue through, it will also definitely pull all of the filtrate through, leaving a pure residue at the top.
What is a valence electron?
Valence electrons are the electrons that are held in the farthest energy shell from the nucleus. Because they are so far from the nucleus, these electrons are weakly held and are the most likely to be involved with interactions with other elements/the environment.
What is vapor pressure?
Vapor pressure is the pressure associated with the gas molecules floating over an equilibrated isolated liquid.
What are kinetic and thermodynamic enolates?
When an enol forms, it can form across the alpha carbons across either side of the molecule. So, if the one of the carbons is more substituted, it will form a more substituted double bond, which is more stable. This is the thermodynamic enolate. If the unsubstituted carbon gets the double bond, the prdouct is less stable. This is the kinetic enolate. Kinetic enolates are favored by rapid, irreversible, low temperature reactions Thermodynamic enolates are favored by slow, reversible, high temperature reactions.
What is the Planck Relation?
Where E is equal to the energy in Joules. f is equal to the frequency in Hz and h is the Planck's constant.
What does the magnetic quantum number tell you?
Which orbital the electrion is in given a subshell. For example, in the p subshell there are three possible orbitals, Px, Py, and Pz. The magnetic quantum number will tell you which orbtial the electron is in.
What is work?
Work is the mechanical transfer of energy from one object to another.
What kinds of reducing agents are needed to reduce carboxylic acids?
You need a strong reducing agent like LiAlH4. Weaker agents like NaBH4 are not strong enough to reduce carboxylic acids.
How do we convert a second order reaction graph into a line graph?
You plot 1/concentration versus time. The slope of the line will be equal to the rate constant.
How do you solve for variables in the exponent of euler's number?
You use the natural log to cancel euler's number and bring the exponent down. 2 Examples shown below. ln (e^x) = x ln (e^5x+6) = 5x + 6 Remember, whatever you do to one side of the equation, you must do to the other! Natural log both sides.
What happens when you take the log of a number to the exponent?
loga^b=B*loga When you take the log of a number to the exponent, you can take the exponent down and multiply the log by it. NOTE: This identity is extremely important for solving equations with exponents. This identity allows one to pull a variable out of the exponent and solve for it.
What are the possible values for l?
n-1
What is 13^2?
169
What is the speed of light equal to in a vacuum?
3*10^8m/s
What kind of bonds make up a double bond?
A sigma bond and a pi bond perpendicular to the axis of the sigma bond.
What wavelength is associated with the color violet?
300ish nm
What is the value of Coulomb's constant?
9.0*10^9
When you have two plane polarizers, what angle must they be at in order to block all light?
90 degrees. I=Iocos^2(angle)
What is a dehydration reaction?
A dehydration reaction is a reaction that gives off water. These are usually also condensation reactions.
What is an oxidation number?
An oxidation number is the number of redistributed electrons on an element in a compound or on its own.
What is body temperature in celsius and farenheit?
37, 98.6
What is the most bonds a carbon will ever have in an organic molecule?
4! This helps us fill in the hydrogens of line angle structures. For example, if there are already two bonds to a carbon, you know the other two substituents are the undrawn hydrogens. Note, there are carbocations and other such specific cases when carbons will have less than 4 bonds, but you will learn about these and recognize them going forward.
What is the specific heat of water?
4.184 J/(g*K) or 1 cal/(g*K)
What is the NMR shift associated with alkene protons?
4.6 to 6 ppm
What is planck's constant equal to?
6.626*10^-34 J-s
What wavelength is associated with the color Red?
700ish nm
What is the NMR shift associated with aldehyde protons?
9 to 10 ppm
What is an aldehyde?
An aldehyde is a molecule with a carbonyl at the end of the carbon chain.
What is the formula for Capacitance?
C = Q/V
What is it called when a liquid goes to solid?
Freezing or Solidification
Where are the Halogens on the periodic table?
Group 17.
Describe intramolecular anhydride formation.
In molecules with aromatic rings and carboxylic acids, the carboxylic acids can attack one another to form anhydrides.
In what direction will charges spontaneously move?
In the direction of lower electric potential energy.
Which is the first quantum number?
The principal quantum number, n.
What is Newton's Third Law?
To every action(force), there is always an opposed but equal reaction.
How does one use the right hand rule?
for C = A x B 1. Point thumb in the direction of vector A 2. Point fingers in the direction of vector B 3. The direction your palm is facing is the direction of vector C
What is the difference between k and Keq
k is the rate constant for the rate law equation. Keq is the equilibrium constant for the equilibrium expression.
How do you calculate Keq from k?
k of the forward reaction (kf) divided by k of the reverse reaction (kr)
What happens when you take the log of a fraction?
log(a/b)=loga-logbWhen you take the log of a fraction, you take the log of the numerator and reduce it by the log of the denominator.
What happens when you take the log of a denominator?
log1/a=-loga When you take the log of a denominator, it is the same as taking the negative log of the reciprocal.
What is the equation for the heat of transformation?
q = mL where q is heat, m is the mass of the substance, and L is the heat/g of the phase change in question.
What are the three guidelines with which one can assess the stability of a resonance structure?
1. A Lewis structure with small or no formal charges is more stable than a lewis structure with large formal charges. 2. A Lewis structure with less separation between opposite charges is preferred over a Lewis structure with a large sepearation of opposite charges. 3. A Lewis structure with negative formal charges on electronegative atoms is more stable than a lewis structure with negative formal charges on electropositive atoms, and vice versa.
How are alcohols named as substituents and parent chains?
1. Alcohol substituents are given the name (hydroxy-) 2. Alcohol parent chains replace -ane with -ol.
What are some functional groups that commonly act as acids?
1. Alcohols 2. Aldehydes (at alpha carbon) 3. Ketones (at alpha carbon) 4. Carboxylic Acids
How are alkanes named as substituents and parent chains?
1. Alkane substituents are given the suffix -yl. For example, Meth-yl, Eth-yl, Prop-yl. 2. Alkane parents are given the default parent name, which is -ane. For example, Methane, Ethane, Propane.
How are alkenes named as substituents and parent chains?
1. Alkene substituents are interesting. You actually modify the parent name still, changing the -ane into -ene, but then you let the highest order functional group partially overwrite it. For example, an alcohol with an alkene will have the suffix -carbon # enol instead of -anol. 2. Alkene parent chains replace the -ane of the parent name with carbon#-ene.
What are the 7 general solubility rules for water?
1. All salts containing NH4+ and alkali metal cations are water soluble. 2. All salts containing NO3- and CH3COO- anions are water soluble. 3. Halides (Cl, Br, I) excluding fluorides are water soluble, with the exception of those formed with Ag+, Pb2+, Hg2+ (heavy metals) 4. All salts containing SO42- are water soluble with the exception of those formed with Ca2+, Sr2+, Ba2+, Pb2+. 5. All metal oxides are insoluble, with the exception of those formed with CaO, SrO, BaO. the alkali metals, and ammonium. 6. All hydroxies are insoluble, with the exception of those formed with Ca2+, Sr2+, Ba2+, the alkali metals, and ammonium. 7. All salts containing CO32-, PO43-, S2-, and SO32- are insoluble, with the exception of those formed with the alkali metals and ammonium.
In general, what are good strategies for balancing equations?
1. Balance the least represented elements first and then move on to the more represented elements. 2. When you get stuck, take a guess for the coefficient of the first reactant and balance the remainder of the reaction appropriately. Afterwards, take out any common factors that are present and you will get the right balanced equation.
How do you name carboxylic acids as substituents and parent chains?
1. Carboxylic acids are the highest order functional group one would expect to see on the MCAT, so if you see a carboxylic acid it won't be a substituent, it'll be the parent. But, if there are multiple carboxylic acid groups, the substituents can be named as carboxy- 2. Carboxylic acid parents are named by replacing the -e of the parent name with -oic acid
What are factors that affect nucleophilicity?
1. Charge: Nucleophilicity increases with increasing electron density (negative charge) 2. Electronegativity: Nucleophilicity increases with decreasing electronegativity because the electrons can freely leave the atom to attack. 3. Steric Hindrance: Bulkier molecules are less nucleophilic 4. Solvent: Protic (acidic) solvents can hinder nucleophilicty by protonating the nucleophile and neutralizing its negative charge.
What are the 6 major kinds of reactions seen on test day?
1. Combination 2. Decomposition 3. Combustion 4. Single Displacement 5. Double Displacement 6. Neutralization
How does one use a ray diagram?
1. Draw 2 or 3 of the important rays (defined in another flashcard) coming from the top of the object and their reflections as they hit the mirror/lens. 2. See if the rays intersect in front of the mirror/behind the lens. If they do, that point of intersection corresponds to the top of a real image and one can determine the properties of the image. 3. If the rays do not intersect in front of the mirror/behind the lens, continue the rays through the mirror/thel ens and see if they intersect. If the rays intersect behind the mirror/ in front of the lens then you have a virtual image.
How do we assign a shape to a molecule?
1. Draw its lewis structure 2. Count the number of bonding and nonbonding electrons on the central atom. 3. Match the number of bonding and nonbonding electrons with the shape predicted by VSEPR Theory.
What are the three carboxylic acid derivatives?
1. Esters 2. Amides 3. Anhydrides
What are the solubility based extraction procedures?
1. Extraction 2. Filtration 3. Recrystallization
How do you solve for the concentration of products for a reaction given an equilibrium expression?
1. First, write the equilibrium expression for the reaction. Let's use the reaction A <> B + C for an example. 2. Second, if the reaction is 1 to 1, like this one is, the amount of reactant lost, x, will be equal to the amount of product gained, x. If the reaction is not 1 to 1, figure out how many moles of product you'd get for each mole of reactant using the stoichiometric coefficients. 3. Next, plug in the Equilibrium constant, in this example, 10-12 and the unknown concentrations of the reactants and products. 4. Finally, if Keq is more than 2 orders of magnitude less than the concentration of the reactants, then the x at the bottom of the equation can be ignored. 5. Solve for x! K=P/R
What are the 5 assumptions of the kinetic molecular theory?
1. Gases are made up of particles with negligible volumes compared to the container. 2. Gas atoms exhibit no intermolecular attractions or repulsions. 3. Gas particles are in continuous random motion, undergoing collisions. 4. Collisons between gas molecules are elastic, meaning energy and momentum are conserved. 5. The average kinetic energy of gas particles is proportional to the absolute temperature of the gas.
What are the steps of the scientific method?
1. Generate a testable question. 2. Gather Data and resources 3. Form a hypothesis 4. Collect new data 5. Analyze the data 6. Interpret the data and existing hypothesis 7. Publish 8. Verify results
What are common ammonia derivatives that react with aldehydes and ketones?
1. Hydroxylamine, H2N-OH, forms Oximes 2. Hydrazine, H2N-NH2, forms Hydrazones 3. Semicarbazide, H2N-NH-C(O)NH2, forms Semicarbazones.
What is the basic approach to a stoichometry problem?
1. Identify and balance the equation associated with the reaction in question. 2. Use whatever information was given (a mass, a pressure, a concentration, etc.) to get moles. 3. Use the mole ratio in the balanced equation to convert from moles of the given to moles of the required. 4. Convert from moles of required into the appropriate unit.
What are the various types of column chromatographies?
1. Ion Exchange Chromatography 2. Size Exclusion Chromatography 3. Affinity Chromatography (Note: All of these are covered in depth in the biochemistry flashcards.)
What are the characteristics of ionic compounds?
1. Ionic compounds have very high melting and boiling points. 2. Ionic compounds dissolve readily in water and other polar solvents. 3. Ionic compounds form crystalline lattice structures so as to maximize the attractive force between atoms of opposite charges and minimize the repulsive force between atoms of same-sign charges.
What are the 6 steps to problem solving O-chem problems?
1. Know your nomenclature and be able to draw molecules. 2. Identify the functional groups. 3. Identify the reagents. 4. Identify the most reactive functional group(s) 5. Identify the first step of the reaction 6. Consider Stereoselectivity.
What are the 4 types of intermolecular forces?
1. London Dispersion Forces 2. Dipole-Dipole Interactions 3. Hydrogen Bonding 4. Ionic Bonds
What are the two criteria that a balanced equation reaction must fulfil?
1. Mass must be conserved (same number and types of elements on both sides of the equation). 2. Charge must be conserved (same overall charge on both sides of the equation).
What are measures of central tendency?
1. Mean 2. Median 3. Mode
What is the naming convention for 1, 2, 3, and 4 carbon molecules?
1. Methane 2. Ethane 3. Propane 4. Butane Note, the (ane) is just what these would be called if they were alkanes. The root is what is important here.
What are the two types of geometries that VSEPR theory can give you?
1. Molecular Geometry - the shape of the molecule 2. Electronic Geometry - the distribution of electrons in a molecule NOTE: 2 different molecules can have equivalent electronic geometry but have differerent molecular geometry. This is because, although two molecules can have equivalent electronic geometry, some of those electrons might be bound to atoms in bonds while others may just be free floating as non-bonding pairs.
How does one find the overall enthalpy of a multistep reaction?
1. Note the enthalpies of each step. 2. Combine the steps in such a way so as to only express the first step and the last step. This is done by flipping equations or multiplying them by numbers so that everything except the first reactant and the last product cancel out. 3. If an equation was flipped, change the sign of its enthalpy. If an equation was multiplied by a number, multiply the enthalpy by the same number. 4. Add the enthalpies up, and you will get the enthalpy of the overall reaction.
How does one use the modified right hand rule for current in wires?
1. Point your thumb in the direction of the current. 2. Wrap your fingers around the current carrying wire. 3. Your fingers now represent the direction of the magnetic field curlng around the wire.
What are the 8 state functions?
1. Pressure (P) 2. Density 3. Temperature 4. Volume 5. Enthalpy 6. Entropy 7. Potential Energy 8. Gibbs Free Energy
What are the Cahn-Ingold-Prelog priority rules?
1. Priority is assigned based on the atomic number of the first atom of the substituent. The higher the atomic number the higher the priority. 2. If there is a tie between the first atoms of two or more substituents, move to the next atom and use the atomic number there to break the tie. Continue as necessary. 3. Atoms that are double bonded in the substituent are counted as if there are two of those atoms bonded.\
What are the measures of distribution?
1. Range 2. Interquartile Range 3. Standard Deviation
What are the two types of Eo's?
1. Reduction Potential 2. Oxidation Potential
How does one determine the quartiles of a data set?
1. Sort the data in ascending order 2. To get the first quartile, multiply the number of data points by 1/4th. 3. If this is a whole number, the quartile is the mean of the value at that data point and the next highest data point. 4. If this is a decimul, round up to the next whole number and take the data point there as the quartile position. To get the second, third, or fourth quartile, simply modify step 2 by multiplying by 2/4ths, 3/4ths, and 1 respectively.
What are the 4 types of newman projections?
1. Staggered a. Anti - Two largest groups are 180 degrees apart b. Gauche - Two largest groups are 60 degrees apart 2. Eclipsed a. Eclipsed - Two largest groups are 120 degrees apart b. Totally Eclipsed - Two largest groups are 0 degrees apart
What are the 2 important differences between static friction and kinetic friction
1. Static friction takes a range of values. Kinetic friction, on the other hand, is constant and does not depend on contact area, velocity of sliding objects, etc. 2. The coefficient of static friction is always higher than the coefficient of kinetic friction. This means accelerating a static object takes more force than accelerating an already moving object. Furthermore, the maximum static frictional force will always be larger than the kinetic frictional force.
What are the two ways we can organically synthesize amino acids?
1. Strecker Synthesis (Strecker uses Cyanide) 2. Gabriel Synthesis (Gabriel uses Rings)
What three factors affect how much plane polarized light is rotated?
1. The identity of the molecule doing the rotating 2. The concentration of the molecule in the solution 3. The length of the tube through which the light is passing (more length means it hits more molecules and gets rotated more)
What are the three ways to calculate work done on or by a system?
1. W=dKE 2. W=PdV 3. W=F*d*coso
What is a beta dicarboxylic acid?
A beta dicarboxylic acid is a dioic acid with 1 carbon in between the carbonyls. These molecules are interesting because their alpha hydrogen is also pretty acidic. Remember, this phenomenon is seen in any 1,3- dicarbonyl compound.
What is a bonding orbital?
A bonding orbital is a molecular orbital where the two atomic orbitals overlapping have the same sign, and therefore add up to a higher magnitude orbital.
What is a capacitor?
A capacitor is an electrical element that can store energy within itself.
What is a carbanion?
A carbanion is a carbon atom with a lone pair and a negative charge. Carbanions are very unstable and need to be stabilized if they're going to last for any meaningful amount of time.
What is a catalyst?
A catalyst is something that lowers the activation energy of a reaction without being used up in the reaction.
What is a positively charged atom called?
A cation MNEMONIC: Cats are Pawsitive (positive)
What is a chair flip and how does it affect the molecules conformation?
A chair flip is when one chair form converts to the other possible form. In a chair flip, the cyclohexane briefly passes through a fourth conformation called the half-chair conformation. After the chair flip is complete, the cyclohexane molecule will still be in chair conformation, but all the axial bonds will now be equatorial and all the equatorial bonds will be axial. However, the components that were facing "up" are still facing "up" and the components facing "down" are still facing "down".
What is a chiral center?
A chiral center is a carbon with 4 different substituents and no internal plane of symmetry. (Remember, we don't draw hydrogens in line angle structures, so the 4th substituent on those chiral centers is a hydrogen.)
What is a closed pipe?
A closed pipe is a pipe that is closed at one end and open at the other end, so one end supports a node and the other end supports an antinode.
What is an example of a constant pressure calorimeter?
A coffee cup calorimater is a constant pressure calorimeter. The incident pressure is atmospheric pressure, and the pressure is constant throughout the reaction.
What is a cohort study?
A cohort study records a group of people as they progress through time, and then assesses the rate of a certain outcome.
What is the archetypal form of the combination reaction?
A combination reaction is when two or more reactants come together to make 1 new product.
What is the archetypal form of the combustion reaction?
A combustion reaction is when a fuel is oxidized to create CO2 and H2O. The fuel will almost always be a hydrocarbon of some sort. The oxidizing agent will almost always be Oxygen.
When will a concave meniscus form?
A concave meniscus forms when the adhesive forces of the liquid are greater than the cohesive forces (the liquid prefers sticking to the wall than to sticking to itself.)
What is a conductor?
A conductor is any material that distributes charge over its surface and transfers charges well. Most metals are conductors. Ionic solutions are also effective conductors. Loose valence electrons that are able to jump from one object ot another
What is a confidence interval?
A confidence interval is a range of data in which you are some x percent sure that the real value falls in. For example, a 95% confidence interval from data you are analyzing that goes from 1 to 5 means you are 95% sure that the real value of the data is somewhere in between 1 and 5. If confidence intervals overlap, then there is not statisically significant difference! 95% sure the real mean is in this range somewhere.
What is a confounding variable?
A confounding variable is a variable that actually serves as the bridge between two seemingly directly related variables.
When will a convex meniscus form?
A convex meniscus will form when the cohesive forces of the liquid are stronger than the adhesive forces (the liquid prefers sticking to itself over sticking to the walls of the container.)
What is a coordinate covalent bond?
A coordinate covalent bond is when one atom contributes both of the electrons that the atoms will share to form their covalent bond.
What is a covalent bond?
A covalent bond is one or more electrons from each atom are shared between the two (or more) atoms. This is usually how nonmetals bind other nonmetals because both of the nonmetals in the bond want to gain electrons.
What is a crystal lattice?
A crystal lattice is the way the atoms of an ionic bond will situate themselves in a group so as to minimize the energy of the system and stabilize the compound.
What is a meniscus?
A curving of the surface of a liquid in a container that is due to the cohesive and adhesive forces in the liquid.
What does a dash represent?
A dash represent something going into the plane of the page, away from you.
What is the archetypal form of the decomposition reaction?
A decomposition reaction is when one reactant breaks down into two or more products.
What is a diastereomer?
A diastereomer is a molecule that is non-super imposable but is not a mirror image of another molecule. This can only really happen when there are more than one chiral centers, so it's a good idea to be thinking about diastereorism whenever you see multiple chiral carbons in a molecule.
What is a diol?
A diol is a molecule with two alcohols. These molecules keep the -ane parent name and adds the suffix -diol
What is a directional alternative hypothesis?
A directional alternative hypothesis is a hypothesis that believes there is a difference between two populations and it also hypothesizes the direction of that difference. For example, Population A is richer than Population B, or drug A works more effectively than drug B.
What is a Disproportionation Reaction?
A disproportionation reaction is a reaction in which one species is reduced and oxidized simultaneously. Example below.
What is a double blinded study?
A double blinded study is a study in which neither the subject or the researcher knows whether they are in the experimental or control group.
Describe the graph of a first order reaction?
A first order reaction means the rate of the reaction is dependent on the concentration of the reactant. So, as the reaction progresses and the amount of reactants decreases, the reaction rate decreases. So the less reactant there is, the more slowly it gets used up. This manifests in the graph as a fast decline that gradually flattens out. A.K.A, an inverse exponential graph. NOTE: We cannot calculate the slope of this graph, it must be converted into a line graph.
What is a Fischer projection?
A fischer projection is a way of representing 3D molecules in 2D space. The fischer projection is a cross where the center is the carbon of interest, the vertical arms are moving away from you, and the horizontal arms of the fischer projection are coming out at you. It is not optional that the arms of the fischer projection are coming out at you. Notice in the molecule below how the carbon 3rd carbon had to get rotated so that the fischer projection would be correct.
What is a hydrazone?
A hydrazone is a modified version of an Imine. In this molecule, the double bonded nitrogen has a nitrogen attached.
What is a hypothesis?
A hypothesis is an educated guess answer to the testable question you generated. It is usually formualted as a if-then statement. For example, your hypothesis might be that if you eat 4000 calories a day, then you will get fat.
What is a jones oxidation?
A jones oxidation is just a very strong oxidation. It is conducted by using CrO3 with Sulfuric Acid H2SO4 and Acetone. Although this oxidation is very strong and has its own name, it acts just like any other strong oxidizer would.
What is a ketone?
A ketone is a molecule with a carbonyl somewhere inside the carbon chain, not at the end.
What is a lactam?
A lactam is an amide in a cyclic system. They are often named by indicating the greek carbon that was attacked in the cyclization of the molecule.
What is a lactone?
A lactone is a cyclic ester. Like lactams, they are often named according to greek lettering.
What is a lewis structure?
A lewis structure is a representation of a molecule in which unbonded valence electrons are represented as dots and covalently bonded electrons are represented as lines. Each dot is equivalent to one electron. Each line is equivalent to two electrons (because you need 2 electrons to make a covalent bond, one for each atom to share.)
What is a ligand?
A ligand is the electron pair donor molecule that attaches to the electron accepting core.
What is an equipotential line?
A line on which the potential at every point is the same.
What does a log graph look like?
A log graph rises quickly at first but slows down and flattens out.
What is a longitudinal wave?
A longitudinal wave oscillates in the same direction as the movement of the wave.
What is a meso compound?
A meso compound is a compound that has chiral centers, but doesn't exhibit optical activity. This is only possible in molecules that have internal planes of symmetry, which just means you can cut the molecule into two identical halves some how. L and D will show optical activity, but the meso- compound below won't.
What is a neutron?
A neutron is an uncharged sub atomic particle in the nucleus of an atom.
What is a newman projection?
A newman projection is a way of looking at molecules to better understand conformational isomerism. In this projection, one looks down the bond and represents the substituents of the front and back carbons with lines to the appropriate groups.
What is a nitrile?
A nitrile is a carbon triple bonded to nitrogen. This is usually a result of a reaction with Cyanide (C triple bonded to N). Cyanide below
What is a node?
A node is a point on a standing wave at which there is no amplitude.
What is a nondirectional alternative hypothesis?
A nondirectional hypothesis states that two populations are not equal, but it doesn't elaborate on how. For example, Population A and Population B are not as wealthy as eachother. Or Drug A and Drug B do not have equal effectiveness.
What is the p value?
A p value is a number that is generated from statistical tests that says the following. This is how likely that the trend in this data is just due to random chance. For example, a p value of .99 means that there is a 99% chance that the data trend is just due to random chance. On the other hand, a p value of .01 means that there is a 1% chance that the data trend is due to random chance. As you can see, we want low p values in our research.
What is a period in regards to the periodic table?
A period is a horizontal row on the periodic table.
What is a pi bond?
A pi bond is a bond that occurs between two lined up p-orbitals. In this bond their electron clouds overlap and a bonding molecular orbital is formed.
What is a positive control?
A positive control is used to ensure a change in the dependent variable when it is expected. For example, you might use a new HIV test on people you know have HIV (positive control) to make sure it works.
What is a path/process function?
A process function is a thermodynamic property that is a function of the path taken to a certain state.
What is a proton?
A proton is a postively charged sub atomic particle found in the nucleus of an atom.
What is a vector
A quantity with a number and a direction
What is a ray diagram?
A ray diagram is a tool for determining the location of images.
What is a resistor?
A resistor is an electrical element that resists the flow of electrons through itself.
What is a resonance structure?
A resonance structure is a lewis structure that has the same bond connectivity as another lewis structure for the same molecule, it's just that the electrons are arranged differently. Remember, bonds are made of electrons, so the bond orders can change as well. The arrangement of atoms cannot. if the arrangement of atoms is different, the molecule is a constitutional isomer, not a resonance structure.
What is a reversible reaction?
A reversible reaction is a reaction that will establish an equilibrium and exist in some combination of products and reactants.
What is density?
A scalar quantity that describes how much mass is packed into each unit of volume for a given substance.
Describe the graph of a second order reaction
A second order reaction means that the reaction is dependent on the square of 1 reactant or dependent on the product of two reactants. At the start of the reaction there are a lot of reactants, and the reaction goes very fast. This causes the amount of reactants to plummet as they are converted into products. This can be seen on the graph as a steep line downwards at the start of the reaction. As the reaction progresses and there are less reactants, the reaction slows down. This causes the steep dive of the reactants to flatten out, similar to a first order reaction. A second order reaction is just like a first order reaction, it just dives steeper at first and flattens out sooner.
What is a spontaneous reaction?
A spontaneous reaction is a reaction that happens on its own and has a negative Delta G.
What is a structural isomer?
A structural isomer is a molecule with entirely different bonding and arrangement, it just happens to have the same molecular formula. Molecular formula for the below molecules are all C4H9Br
How do you calculate the atomic weight of an atom with two naturally occurring isotopes?
A*X + B*Y = Atomic Weight A is equal to the mass number of the first isotope. X is equal to the percentage prevelance of that first isotope. B is equal to the mass number of the second isotope. Y is equal to the percentage prevelance of that second isotope.
What is the mass of a neutron?
About the same as a proton, 1amu.
What is the difference between accuracy and precision?
Accuracy (also called validity) refers to the ability of something to measure the true value. Precision (also called reliability) refers to the ability of something to measure the same things in the same way, AKA consistently.
How does acid affect every acyl substitution reaction?
Acid will protonate the carbonyl oxygen, making the carbonyl carbon an even better electrophile and pushing the reaction forward. In most acyl substitutions, the acid is just a catalyst. However, if the nucleophile being used is very weak, activating the carbonyl oxygen with acid is a necessary step to get the reaction to happen at all.
What is activation energy?
Activation energy, Ea is the amount of energy it takes to start a reaction between two molecules. This energy is supplied by temperature (more kinetic energy) and orientation (when the molecules hit in a certain way it can generate more or less energy).
What is an acyl derivative?
Acyl derivatives are all molecules with a carboxylic acid derived carbonyl. So this means that the nucleophilic acyl substitution mechanism applies to Carboxylic Adcids, Amides, Esters, Anhydrides, etc.
How can you increase the frequency factor of a reaction?
Add more molecules.
How do we get the molecular weight of a molecule?
Add the atomic weights of the elements that make the molecule up. Remember, we can always refer to a periodic table for the atomic weight of any element.
How does one calculate the equivalent capacitance of capacitors in parallel?
Add up the individual capacitances
What is adhesion?
Adhesion is the attractive force that a molecule feels towards molecules of some other substance.
At what point will heat affect the temperature of an object that is undergoing a phase change?
After the phase change is complete. Changing phases requires its own heat energy and this cost must be paid first. Therefore, heat added to a 0 degrees celsius icecube will only cause the icecube to melt into water, not change the temperature. Once the ice cube is completely water, any additional added heat will raise the temperature.
Which form of radiation is most dangerous if its source is inside the body?
Alpha decay is the most dangerous radiation if its occuring inside the body. This is because the alpha particle is not very penetrating, and won't be able to break out of the body. These particles will just stay in the body doing damage. A gamma ray, though higher energy, will exit the body very quickly due to its penetrance.
What is an alpha hydrogen?
Alpha hydrogens are hydrogens that are attached to an alpha carbon (one away from the carbonyl). These hydrogens are of above average acidity because the conjugate base can be resonance stabilized.
What does an ammeter measure?
Ammeters measure current at some point in the circuit.
What is an Angstrom and what is its conversion factor?
An Angstrom is a unit of length. The symbol for Angstrom is shown below. 1 Angstrom is 10-10 of a meter.
What is an absorption spectrum?
An absorption spectrum is like the atomic emission spectrum, only instead of cataloguing the photons that are emitted when excited electrons fall, absorption spectra catalogue the photons that are absorbed when ground state electrons are promoted to excited states. Remember, the difference in energy going from energy level 1 to 2 is the same amount of energy as going from energy level 2 to 1, so the photons emitted by the emission spectrum are the same photons absorbed in the absorption spectrum.
What does it mean to be adiabatic and how does that affect the first law of thermodynamics equation?
An adiabatic process is one in which there is no change in heat. Q=W
What is a-racemization?
An aldehyde or ketone with a chiral alpha carbon will rapidly become a racemic mixture due to keto-enol tautomerization. Keto-enol tautomerization is non-stereospecific, so it will just randomly convert stereoisomers back and forth, generating a racemic mixture.
What is an alkane?
An alkane is an organic molecule with a highest priority functional group of a Carbon - Hydrogen bond. Note, this is basically the default for organic molecules, and so it follows that alkanes are the absolute lowest priority functional group.
What is an alkene?
An alkene is a molecule with a double bond.
What is an alkoxy group?
An alkoxy group is a carbon moiety that is attached to the parent chain through an oxygen bond.
What is an alkyl halide and how are they named?
An alkyl halide is a halogen bound to a normal carbon (not a functional group of import). Alkyl halides are always substituents and are named by adding an -o to to their root element name.
What is an alkyne?
An alkyne is a molecule with a triple bond.
What is a negatively charged ion called?
An anion
What is an anode?
An anode is where oxidation occurs.
What is an aromatic compound?
An aromatic compound is a conjugated ring system that follows Huckel's Rules. These compounds are very stable!
What does it mean for an atom to be in an excited state?
An atom is excited when one of its electrons is in a higher energy shell than it would normally be.
What does it mean for an atom to be in ground state?
An atom is in ground state when all of its electrons are in the lowest possible energy shells they can occupy.
What is meant by primary, secondary, tertiary, and quaternary in the context of organic chemistry?
An atom is said to be primary, secondary, tertiary, or quaternary based on the number of carbons to which it is bound.
What is an atom's mass number?
An atom's number is equal to the number of protons plus the number of neutrons in the nucleus. Essentially, mass number is equal to the total mass of the atom (because electrons give so little mass they are not accounted for.)
What is an atomic emission spectrum?
An atomic emission spectrum is a cataloguing of all the electron transitions an atom can undergo and the photons those transitions release. Remember, the distances between energy levels are different in every atom. Therefore, the photons released when an electron falls from an excited state to ground state are different in every atom. We can use the photons an atom releases to determine its identity.
What is an electrical circuit?
An electrical circuit is a conducting path (usually achieved through wires) connecting one or more voltage sources (battery) to one or more passive circuit elements (capacitor, resistor, etc.)
Describe the diversity of electrochemical cells.
An electrochemical cell can be made out of almost anything, as long as there is a cathode and an anode of some sort connected by something. This is seen in batteries as solution reactions connected by wires, but it can be seen in the body as two sides of the mitochondria connected by a plasma membrane. As long as there is flow of electrons, there is potentially an electrochemical cell at play.
What is an electrochemical cell?
An electrochemical cell is an anode and a cathode connected somehow that captures the flow of electrons to harness energy.
What is an electrolytic cell?
An electrolytic cell is an electrochemical cell in which electrons are going from high reduction potential to low (still anode to cathode), and this requires the input of energy.
What is an electrolytic solution?
An electrolytic solution is a solution with dissolved ions. These solutions can conduct electricity through themselves. Nonspontaneous.
What is an electron?
An electron is a negatively charged particle that orbits the nucleus of an atom.
What is an electrophile?
An electrophile is an atom that is attracted to the negative charge of the electrons on other atoms. Generally electrophiles have a positive charge or are in a dipole-dipole bond that gives them a partial positive charge.
What is empirical formula?
An emprical formula is the most-reduced whole number ratio of the atoms in the compound.
What is an enol?
An enol is a molecule with a double bond and an alcohol.
What is an enolate?
An enolate is a deprotonated enol. Enolates are better nucleophiles than enols.
What is a equilibrium expression?
An equilibrium expression is a way to calculate the concentrations of products and reactants at equilibrium.
What is an intermediate?
An intermediate is a product that is produced in one of the steps of the reaction and then consumed in one of the other steps. The intermediate does not show up in the final product for this reason.
What is an ionic bond?
An ionic bond is when one or more electrons from one atom are transferred to a different atom. This is usually how metals and nonmetals bond, because metals really want to get rid of a few electrons and nonmetals really want to gain a few electrons.
What is an irreversible reaction?
An irreversible reaction is a reaction that goes forward to completion, and makes the full amount of product possible given its reactants.
What is an isolated system?
An isolated system is a system that is incapable of exchanging energy or matter with its surroundings. It follows that the total change in internal energy in an isolated system will be equal to 0.
What is an isotope?
An isotope is an atom that shares an atomic number (number of protons) with another atom but has a different mass number by virtue of having more/less neutrons.
What is Newton's First Law?
An object at rest or in motion with constant velocity will remain that way unless a force acts on it.
What is Netwon's Second Law?
An object of mass m will accelerate when the vector sum of the forces results in some nonzero resultant force vector.
What is an open boundary?
An open boundary is a boundary that allows maximum oscillation because it really isn't a boundary. Examples of an open boundary are the free end of a flag and the open end of a pipe.
What is an open pipe?
An open pipe is a pipe that is open at both ends, and so both ends of the pipe support anti nodes.
What is an optical isomer?
An optical isomer is an isomer that changes the way the molecule rotates plane-polarized light. Enantiomers and Diasteromers are both considered optical isomers.
What is an organic phosphate?
An organic phosphate is a phosphate containg compound that also contains carbons. ATP, GTP, Nucleotides, etc are all organic phosphates.
What is an outlier?
An outlier is a data point that is extremely large or small when compared to the other data points.
What is the standard deviation of outliers?
An outlier is any number that lies more than 3 standard deviations from the mean.
What is an oxidation potential?
An oxidation potential is the standard potential of an oxidation reaction.
What is an oxime?
An oxime is a modified version of an Imine. In this molecule, the double bonded nitrogen has a hydroxyl group attached.
What does it mean to be an unsaturated solution?
An unsaturated solution is a solution that has not reached the maximum amount of dissolved solute as defined by the ksp. Solute added to an unsaturated solution will dissolve.
What is angle strain?
Angle strain is the strain introduced into a molecule whenever bond angles deviate from ideal. This strain makes the molecule less stable.
Describe the cleavage of anhydrides.
Anhydrides can be cleaved with various nucleophiles using the standard nucleophilic acyl substitution mechanism.
How big must the difference in electronegativity be to be considered a polar bond?
Any electronegativity difference between 0.5 or 1.7 will seperate charge enough to create a polar bond.
Describe electric fields
Any given charged particle will create an electric field that radiates outward or inward in all directions. Charged particles that enter the electric field of a different object are liable to experience electrostatic forces.
What is the second law of thermodynamics?
Any given process must result in an increase in total entropy in the universe. In other words, things cannot go from disordered to more ordered spontaneously. For a specific example, consider heat. Heat will not flow from a cold object to a hot object, decreasing entropy. Instead, heat will always from a hot object to a cold object in thermal contact until the temperatures of the objects are equal and the entropy of the universe is higher.
How do we use IQR's to justify the existence of outliers?
Any number that falls more than 1.5 IQR's outside of the data set is considered an outlier.
How big must the difference in electronegativity be to be considered an ionic bond?
Any two elements with an electronegativity difference of greater than 1.7 will form an ionic bond. This is because the difference in electronegativity is so big that one of the atoms just takes the electrons from the other one instead of sharing them.
In a reaction with two possible products, how do you get the kinetic product?
Apply low temperature to the reaction.
What is Archimedes' principle
Archimedes' principle states that an object in a fluid will be pushed upwards by a force that is equal to the weight of the fluid it displaces. F/A=F/A principle states that a body wholly or partially immersed in a fluid will be buoyed upwards by a force equal to the weight of the fluid it displaces
Describe the relative energies of the newman conformations
As shown below, the 2 anti-staggered configurations @ A and G are lowest energy and most stable (least steric hindrance). Next in terms of energy are the two gauche configurations @ C and E Next in terms of energy are the two eclipsed configurations @ B and F Finally, the highest energy conformation is the totally eclipsed configuration, which can only manifest itself one way, as seen @ D.
What is the purpose of a salt bridge?
As the cathode gets more and more electrons, it starts to build up a negative charge. The anode starts to build up a positive charge as it loses electrons as well. As the anode and cathode diverge from their original charges, the reaction becomes less efficient and progresses less vigorously. The salt bridge fixes this problem. The bridge is filled with inert ions that will affect the charge of the solution without reacting with the redox-reaction. The cations in the salt bridge will go to the cathode to cancel out the negative charge build up, and the anions will go to the anode to cancel out the positive charge build up.
Describe the Hill Criterion of Consistency?
As you increase the number of settings in which you can relate an independent variable to a dependent variable, the more likely there is an actual causal relationship between them.
What is atomic weight?
Atomic weight is the weighted average of all the different stable isotopes one might find of an atom. For example, Chlorine naturally occurs in the 35 and 37 mass number. Therefore, the atomic weight of chlorine is equal to the weighted average of the mass number of its naturally occurring isotopes.
What is happening when an electron is promoted to a higher energy level?
Atoms gain energy all the time from increases in temperature, collisions with other atoms, and from being struck by photons (most common method). If an atom gains the exact amount of energy required to promote an electron from one energy level to another, it will do so.
What is Beta minus decay?
Beta decay is when an unstable nucleus emits a beta minus particle AKA an electron. This happens when neutrons in the nucleus break down into a proton and an electron. The proton stays in the nucleus, increasing the atomic number but conserving the atomic mass. The electron is emitted as the beta particle.
How does bias affect research?
Bias is systematic error and results from a problem during data collection. Bias will skew the numbers in one direction, either up or down.
What physical property does distillation take advantage of to separate compounds?
Boiling point!
Where in relation to the element symbol are the atomic number and mass number located?
Bottom left and top left, respectively.
How do you read Box Plots?
Box Plots, also called box-and-whisker plots, are read as follows. The box represents the IQR. The line in the box represents the median. The whiskers at the top and bottom of the plot refer to the highest and lowest values in the data set, which can be used to determine the range of the data.
What is Boyle's Law?
Boyle's Law states the pressure and volume of a gas are inversely proportional.
Describe the -OH IR peak
Broad peak in the 3300cm-1 region
What is capacitance?
Capacitance is defined as the ratio of the amount of charge built up on either plate of the capacitor to the magnitude of the voltage across the capacitor. remember that capacitance must be a positive value.
How are alcohols used as protecting groups?
Carbonyls are susceptible to reduction, and so in reduction reactions where you don't want to lose the carbonyl, you need to protect it somehow. This is accomplished by reacting aldehydes and ketones with 2 eq of alcohol or 1 eq of a diol to form acetals or ketals. Acetals and ketals are not easily reduced. So, you convert the carbonyl into an acetal or ketal, reduce the molecule the way you want to, and the convert the acetal or ketal back into a carbonyl by treating it with aqueous acid.
Describe the characteristic physical properties of carboxylic acids.
Carboxylic acids have both a hydrogen bond donor (-OH) and a hydrogen bond acceptor (C=O). This means they can engage in many hydrogen bonds, which results in high intermolecular forces and high boiling and melting points. The other important characteristic of carboxylic acids is their acidity! The -O- is resonance stabilized after deprotonation, which makes the conjugate base stabilized. Note, most carboxylic acids will still only be weak acids. They still don't compare to the strong acids like HCl annd H2SO4
What is a Case Control study?
Case control studies assess outcomes between groups and then assess those groups history to see if they were exposed to different or similar things.
How do catalysts speed up reactions?
Catalysts are molecules that in some way shape or form stabilize the transition state of the reaction and lower its energy. This in turn lowers the activation energy of the reaction, which is used in the Arrhenius equation to determine the rate constant of the reaction.
What conformations does cyclohexane take to make ring strain as low as possible?
Chair, boat, and twist.
What does multiplying a vector by a negative number do?
Change the magnitude and direction of the vector.
Only charges moving {{c1::perpendicular}} to the magnetic field will feel a force of any sort.
Charges running parallel will not feel the magnetic force. 0 Magnetic force.
What is chelation?
Chelation is when a central cation is bonded to the same ligand in multiple places. This generrally requires large organic ligands that can double back to form more bonds with the central atom.
What are chemical properties?
Chemical properties are characteristics of processes that are associated with the chemical (how it reacts), not physical (what it's like) properties. Generally speaking, chemical properties are determined by the functional groups present in the molecule.
What is chemoselectivity?
Chemoselectivity refers to the tendency of chemicals to react with certain functional groups preferrentially over others. For example, in a molecule with an alcohol and a carboxylic acid, a reducing agent is more likely to reduce the very oxidized carboxylic acid over the slightly oxidized alcohol. Chemoselectivity is always related to the mechanism of the reaction. If you understand the mechanism, you'll be able to tell which functional groups will participate and which won't.
How does one break a vector into components?
Choose two axes (vertical & horizontal or parallel & perpendicular) and use two vectors to represent the original vector.
What property does chromatography separate samples based on?
Chromatography uses mobile and stationary phases with different polarities and properties to separate molecules with different properties. The more affinity for the mobile phase, the farther the molecule will travel. The more affinity for the stationary phase, the less the molecule will travel. We can use this to separate molecules from one another. Mobile is NP Stationary is P
What are cis-trans isomers?
Cis-trans (formerly referred to as geometric isomers) are a specific subtype of diastereomer in which two identical substituents (hydrogens are not considered substituents) differ in their position around an immovable bond. Immovable bonds are double bonds and ring bonds. Cis isomers have the single substituent of interest on the same side of the bond, while trans isomers have the single substituent of interest on opposite sides of the bond. In molecules with more than one substituent on both sides of the bond (which really just means there are substituents instead of hydrogens) E and Z nomenclature is used instead.
What are colligative properties?
Colligative properties are physical properties of solutions that are dependent on the concentration of dissolved particles.
"Characteristics of Gases "
Compressible. Large avg distance between the two molecules. Fill the shape of a container. Constant motion. Massless. No IMF
What are the two types of spherical mirror?
Concave and Convex
What is concentration?
Concentration denotes the amount of solute dissolved in a solvent.
What are the units of rate?
Concentration over time, usually Molarity over seconds.
What is conduction?
Conduction is the direct transfer of energy from molecule to molecule through physical collisions. The process of heat conduction depends on the following factors: temperature gradient, cross-section of the material, length of the travel path, and physical material properties. The temperature gradient is the physical quantity that describes the direction and rate of heat travel. Temperature flow will always occur from hottest to coldest or, as stated before, higher to lower kinetic energy. Once there's thermal equilibrium between the two temperature differences, the thermal transfer stops. Cross-section and path of travel both play an important part in conduction. The greater the size and length of an object, the more energy that's required to heat it. And the greater the surface area that's exposed, the more heat is lost. Smaller objects with small cross-sections have minimal heat loss. Physical properties determine which materials transfer heat better than others. Specifically, the thermal conductivity coefficient dictates that a metal material will conduct heat better than cloth when it comes to conduction. The following equation calculates the rate of conduction:
What is constructive interference?
Constructive interference occurs when negative displacement waves interact with negative displacement waves, or when positive displacement waves interact with positive displacement waves. When these types of waves interact, the superposition wave will have a displacement equal to the sum of the individual wave displacements.
What is convection?
Convection is the transfer of heat by the physical motion of a fluid over a material. (Remember, gases and liquids both behave as fluids!) Must occur through a medium. When a fluid, such as air or a liquid, is heated and then travels away from the source, it carries the thermal energy along. At the molecular level, the molecules expand upon introduction of thermal energy. As temperature of the given fluid mass increases, the volume of the fluid must increase by same factor. This effect on the fluid causes displacement. As the immediate hot air rises, it pushes denser, colder air down.
How does one determine the harmonic of a standing wave in a closed pipe?
Count the number of quarter wavelengths.
What is reaction coupling?
Coupling is when you pair two reactions so that their overall delta G is negative and the overall reaction is spontaneous.
What are the characteristics of covalent compounds?
Covalent compounds contain discrete molecular units with relatively weak intermolecular interactions, and therefore lower boiling points and melting points. They do not break down into constituent ions, and are therefore poor conductors of electricity.
When multiplying vectors, what type of product should be used to create a new vector?
Cross Product
What is current?
Current is the amount of positive charge passing through a conductor per unit of time.
What is a cyanohydrin?
Cyanohydrins are molecules with a -CN and -OH group on the same carbon.
What is Dalton's Law of Partial Pressures?
Dalton's law of partial pressures states that the total pressure in a container with a mixture of gases will be equal to the sum of the independent pressures.
How does ring strain affect lactams?
Depending on the number of substituents in a ring (5 and 6 are the only real stable ones) the ring strain imparted on a molecule can severely weaken its stability. Even the amide bond, a very strong bond normally, can be easily cleaved if it is shoved into an awkward ring.
What is it called when a gas goes to a solid?
Deposition
What is destructive interference?
Desctructive interference occurs when the a positive displacement wave interacts with a negative displacement wave. The superposition wave will be equal to the sum of the individual wave displacements, but because the waves have opposite signs, the superposition wave will be smaller than either of the individual waves.
What does it mean to be diamagnetic?
Diamagnetic materials are made of atoms with no unpaired electrons and that have no net magnetic field. Repels the magnetic field
How do diamagnetic materials behave when exposed to magnets?
Diamagnetic materials are weakly repelled by magnets (slightly antimagnetic)
What are diatomic molecules?
Diatomic molecules are seven elements that do not exist alone in nature. Instead, they bond with themselves to form more stable di-atomic (2 atom) compounds. They are H2, N2, O2, F2, Cl2, Br2, I2. MNEMONIC: The six in the seven and Hydrogen. Six of the diatomic elements are in a seven shape on the right side of the periodic table, and the only other one is Hydrogen.
How do dielectric materials work?
Dielectric materials are inserted in between the plates of a capacitor in order to increase the capacitance. Because dielectrics are insulators, inserting them in between the plates of a capacitor decreases the strength of the electric field between them. Capacitance is inversely related to the field between the plates, so lowering the strength of the field increases the capacitance.
What is dilution?
Dilution is when you lower the concentration of something by decreasing the moles of solute or increasing the volume of solution.
What is dimensional analysis?
Dimensional analysis is the analysis of the relationships between different phsical quantities by recognizing their basic quantity (length, mass, time, area, volume, etc.) and their unit of measure (miles vs kilometers, grams vs. kilograms, etc.)
What is dispersion?
Dispersion is when various wavelengths of light separate from one another.
What is displacement?
Displacement is a vector quantity that describes an objects change in position in space. It is an arrow from initial position to final position.
What is distance?
Distance is a scalar quantity that describes the length that an object has traveled. It is a tallying of the total length an object has moved to get from its initial position to its final position.
What is distillation?
Distillation is a process by which a mixture of two liquids is separated by boiling one of the liquids out.
How do you find the percent composition of a specific element in a compound?
Divide the specific element's contribution to the molar mass of the compound (can get this from the periodic table) by the total molar mass of the compound and multiply by 100%.
How can we increase the effectiveness of separatory funnel separations?
Do them over and over! At best, you'll pull 99% of the solute you want into one of the layers, but there is always some amount left, and sometimes it can be a lot. So, you can take the filtrate form a sep funnel extraction and run that through another sep funnel extraction to make it even purer.
When multiplying vectors, what type of product should be used to create a scalar?
Dot product
What kind of molecular orbitals go into double bonds?
Double bonds are made of 1 sigma bond with 1 pi bond around it.
What does it mean to have an eclipsed newman projection?
Eclipsed newman projections occur when the substituents are lined up with one another. These can be in either Eclipsed or Totally Eclipsed conformation.
What is Electron Domain Geometry and how do we predict it with VSEPR?
Electron Domain Geometry is the shape made between the electrons on the central atom and the central atom, regardless of whether or not the electrons are in a bond or not. In this case, we simply count up the number of electron pairs, bonded or nonbonded, and refer to VSEPR theory for the shape.
What is Electron Affinity?
Electron affinity is the amount of energy released when an an atom gains an electron. In other words, Electron Affinity describes how easily an atom can capture an extra electron.
What is electron capture?
Electron capture is when an unstable nucleus combines an inner electron with a proton to form a neutron. The neutron stays in the nucleus. This lowers the atomic number while keeping the mass number the same.
What kinds of groups increase the strength of a base?
Electron donating groups near the basic hydrogen. This is because these electron donating groups help to cancel the positive charge of the conjugate acid, stabilizing it. Remember, the more stable the conjugate acid, the stronger the base.
What are common electron withdrawing groups?
Electron withdrawing groups are generally groups that have high electronegativity and pull electrons towards themselves.
What kinds of groups increase the strength of an acid?
Electron withdrawing groups near the acidic hydrogen. This is because these electron withdrawing groups spread the charge density of the conjugate base out, stabilizing it. Remember, the more stable the conjugate base, the stronger the acid.
What is Electronegativity?
Electronegativity is a measure of how much force with which an atom can pull electrons towards itself. The more electronegativity an atom has, the stronger it pulls electrons towards itself.
What does it mean for elements to be in parallel?
Elements in parallel are elements which are placed side by side on different paths. Because there are multiple paths, the current will split and be distributed amongst the elements.
What does it mean for elements to be in series?
Elements in series are elements which are placed sequentially on the same path. Because there is still only 1 path, the each element will have the full current pass through them.
What is an energy shell?
Energy shells are different distances at which electrons can orbit a nucleus with stability. The more energy an electron has, the further out they go.
What is the difference between heat and enthalpy?
Enthalpy is just heat under constant pressure, a commonly made assumption.
What is entropy?
Entropy is the measure of the spontaneous dispersal of energy at specific temperatures. As entropy goes up, more energy gets dispersed or the same ount of energy gets dispersed farther.
What does it mean when we say water follows solutes?
Entropy wants things to go from high concentration to low concentration, and so water will naturally flow into places of high concentration in order to lower the concentration.
What conformation does cyclopentane take to make ring strain as low as possible?
Envelope
What is Eo?
Eo is the standard potential. It is the potential change associated with the reaction being described.
What is it called when a liquid goes to a gas?
Evaporation or Vaporization
What is the difference between evaporization and boiling?
Evaporization is the natural conversion of some liquid molecules into gas that occurs as a result of the equilibrium between the phases. Boiling is the rapid bubbling of the entire liquid with the rapid release of the liquid as gas particles. This happens when the liquid exceeds its boiling temperature.
What does it mean to be ferromagnetic?
Ferromagnetic materials, like paramagnetic materials, are made of atoms unpaired electrons and randomly oriented magnetic fields that cancel out. The only difference is that ferromagnetic fields become strongly magnetized by magnets as opposed to becomming weakly magnetized by magnets.
Describe Filtration?
Filtration isolates a solid from a liquid. In this method, one pours a liquid-solid mixture through a filter of some sort (usually a paper filter). The liquid will pass through and fill a flask. This is known as filtrate. The solid on the other hand will be left in the filter. This is known as residue.
How do we know how many valence electrons an atom is carrying?
Find the atom's element on the periodic table and make note of what column it is in. That will tell you the number of valence electrons on that element, and therefore an atom of that element.
Describe the Michael Addition
First, a carbanion is generated by deprotonating the alpha hydrogen of a ketone or aldehyde. Next, the carbanion is used as a nucleophile to attack an alpha beta unsaturated carbonyl compound, which is a molecule with a double or triple bond between the alpha and beta carbons of a carbonyl. The double bond in the alpha beta unsaturated carbonyl is pushed to the carbonyl carbon, which pushes carbonyl double bond up to the oxygen. The electrons in the double bond are siphoned by a base, which allows the carbonyl double bond to reform.
Describe the first step of aldol condensation
First, an enolate is formed by treating a carbonyl with a base. The Enolate reforms a carbonyl and a carbanion, which it uses to attack another carbonyl (almost always itself as there shouldn't be multiple carbonyl compounds in the same flask.) At this point, a carbon-carbon bond has been formed. The electrons that got pushed to the oxygen pick up a proton, forming an aldol.
How does one calculate formal charge?
First, draw a square or circle around the atom in which you are interested. Make sure to draw the square or circle in such a way so as to capture all of the unbonded electrons on the atom and to split any bonds on the atom in half. Second, make note of the number of valence electrons normally on the atom in question. You can always get this info from the group number on the periodic table. Last, subtract the number of electrons from the normal number of valence electrons on the atom. Unbonded electrons count as one electrons, and any bond on the atom only counts as one electron because you split the bonds in half with your drawing. The number you get from this calculation will be the formal charge on the atom. Example shown below with both carbon and oxygen.
Describe the first step of the Strecker Synthesis.
First, the carbonyl carbon of the aldehyde is activated by the ammonium's acidic proton. Second, the deprotonated ammonium (ammonia) attacks the activated carbonyl. Third, the hydroxyl group takes the extra proton from the amino group and turns into water, a decent leaving group. Fourth, a double bond forms between the amino group which displaces the water leaving group. Fifth, Cyanide as a nucleophile attacks the double bonded electrophilic carbon to generate an aminonitrile.
Describe the esterification reaction
First, the carbonyl is protonated to increase the electrophilicity of the carbonyl carbon. Then an alcohol uses its free electrons to attack the carbonyl. The original -OH group gets protonated, turning it into water, a decent leaving group. The carbonyl reforms and the water leaving group leaves. Finally, the carbonyl oxygen deprotonates, resulting in an ester.
Describe the synthesis of an amide from a carboxylic acid?
First, the free electrons on the nitrogen attack the electrophylic carbonyl carbon. This pushes the double bond electrons up to the oxygen. Then the alcohol group gets protonated to make it a decent leaving group. Finally, the carbonyl reforms and the water group leaves. Leaving an amide. General mechanism below. Specific example
What is fluorescence?
Fluorescence is when a species absorbs high frequency light, but doesn't emit it all right away. Instead, it emits multiple photons with increasingly less energy in a series of steps where the total energy of the emitted photons is equal to the energy of the absorbed photon. Because the light is being emitted in multiple steps, it takes a lot longer. So, when you shine high frequency light on fluorescent material, it will absorb the light and glow for a while afterwards (Slow emission of many photons) as opposed to just flashing a quick color like it would if it emitted one photon in one step.
What is clinical significance?
For an intervention to be clinically significant AKA practically significant, it must result in worthwhile changes in the health status of an individual.
What is the critical modification one must make to the right hand rule for negative charges?
For negative charges, flip the direction of the vector that resulted from the right hand rule. If the right hand rule tells you the force on a proton is coming out of a page, that means that for an electron, that force will be going into the page.
Transition metal charges can be identified with roman numerals, but they can also be identified with suffices. What are these suffices?
For transition metals with two stable ions, the suffix -ous is used to refer to the lesser charge ion and the suffix -ic is used to refer to the higher charge ion.
What is Hill's Criteria?
For two things that are correlated, Hill's criteria can be used to determine if they are actually correlated. Hill's criteria is as follows. 1. Temporality 2. Strength 3. Dose-Response Relationship 4. Consistency 5. Plausibility 6. Consideration of Alternative Explanations 7. Experiment 8. Specificity 9. Coherence MNEMONIC: The Strange Doctors Consistently Poll Cats, Elephants, Snakes, and Crocodiles
What is formal charge?
Formal charge refers to the difference between the number of valence electrons on an atom in a molecule and the number of valence electrons on an atom in its neutral unbonded state. Generally speaking, the larger the formal charge (in either the negative or positive direction), the less likely that the molecule will arrange itself in that lewis structure.
What is Fractional Distillation?
Fractional Distillation is like simple distillation, except that there is a fractionation column connected to the distillation flask. The purpose of the fractionation column is to give the vapor more surface area on which it can condense. This is useful for liquids with close boiling points. For example, a liquid with a 90C and a liquid with a 100C boiling point will both boil at 90C. It's just that the 90C liquid will boil completely while the 100C liquid will boil a little bit. However, if there is a long fractionation column, the tiny bit of 100C liquid that boils will never make it to the condenser, so you're safe from contaminating your distillate!
What is freezing point depression?
Freezing point depression is the fact that, as you add nonvolatile solutes to a solution, it's freezing point decreases. This is described mathematically below. Where Delta T is the change in freezing point, Kf is a constant, m is the molality of the solution, and i is equal to the number of different particles the solute dissolves into. For example, MnCl2 would dissolve into three ions, so i would equal 3.
As you move from left to right on the periodic table, in what way do elements change?
From left to right elements have an increasing number of protons, electrons, and neutrons. More specifically, going from left to right increases the effective nuclear charge in an atom.
In what direction(temperature wise) does heat flow?
From objects with high temperatures to objects with lower temperatures
What is it called when a solid goes to a liquid?
Fusion or Melting
What is Gibbs free energy?
Gibbs Free energy is the amount of "available" energy associated with a reaction. When Gibbs energy is positive, it means the reaction needs energy made available by the environment to drive the reaction. When Gibbs energy is negative, it means the reaction makes the energy it releases during the reaction available for the environment.
What is Graham's Law of effusion and diffusion?
Graham's law allows us to compare diffusion and effusion rates between gases by relating the square root of their molar masses. Where the r's are the diffusion or effusion rates of the two gases, and the MM's are the molar masses.
What is Gravity Filtration?
Gravity filtration is when the liquid and solid just pass through the filter because gravity pulls them through it. This is the preferred method when you are more concerned with pure filtrate, as it is less likely that any residue will make it through the filter.
Where are the Alkaline Earth Metals on the periodic table?
Group 2.
What is High Performance Liquid Chromatography?
HPLC is a specific type of column chromatography in which high pressures and sophisticated computer systems are used to separate compounds that have even tiny differences in their affinities for the mobile and stationary phase. This is method is preferred for separating compounds that are more similar than they are different.
What is Hess's law?
Hess's law is just a consequence of the fact that enthalpy is a state function. It states that enthalpies of a series of step by step reactions will just add up, and the overall enthalpy of the series of step by step reactions will be equal to the sum of each individual step.
How do we perform extractions?
How do we separate a polar and a nonpolar compound in solution? First, find two immiscible solvents with different polarities. The polar layer is called the aqueous phase and the nonpolar layer is called the organic phase. Mix these in a separatory funnel. Next, place your mixed solution into the separatory funnel with the two solvents. Third, shake it all up, making sure to vent the separatory funnel to let any gas out. Fourth, let it settle out. Remember, the two solvents you picked earlier are immiscible, so over time they will naturally separate, like oil and water. The polar compound in the solution will have dissolved mostly into the aqueous layer and the nonpolar compound in the solution will have dissolved mostly into the organic layer. Carefully separate the layers, and viola, you have separated your two products!
What is conductance?
How easily electrons can flow through a substance. The higher the conductance, the easier it is for electrons to flow through the substance.
What is displacement in the context of waves?
How far away from the equilibrium position the wave is.
What is Hund's Rule?
Hund's rule states that energy of the various orbitals in a sublevel are equal. What this implies is that each orbital in the sublevel will receive one electron before it receives two electrons.
What is hydration?
Hydration is the same thing as solvation, it's just what you call it when water is the solvent.
What are Hydrogen Bonds?
Hydrogen bonds are just a particularly strong dipole-dipole interaction formed when hydrogen binds certain very electronegative elements (F,O,N). Hydrogen bonds are so strong, that they can act as intermolecular forces (attraction between different molecules) or intramolecular forces (attraction between a hydrogen dipole within the molecule and another element within that same molecule). MNEMONIC: Hydrogen bonds pick up the FON (phone): Hydrogen bonds are only seen in molecules containing a hydrogen bound to Fluorine, Oygen, and Nitrogen.
In liquids, what two kinds of pressures can potentially exist?
Hydrostatic pressure and osmotic pressure
What is the Interquartile Range?
IQR is related to the median, first, and third quartiles. Specifically, it is the difference between the third quartile (75th percentile) and the 1st quartile (25th percentile).
What must be true of the molecule and the stretch it undergoes for it exhibit IR absorption?
IR absorption can only happen in dipole molecules with asymmetric stretches. So, that means O2, or Br2 would never show on an IR spectra because they are diatomic and there is no net dipole. Furthermore, even molecules like HCl, which has a dipole, will exhibit IR absorption for all of their motions except the symmetric stretch, which results in no change in dipole moment.
In what direction will the reaction proceed if Q < K?
If Q < K then the ratio of products to reactants is lower then it would be at equilibrium. Therefore, we'd expect the reaction to go in the forward direction to reach the equilibrium ratio.
What are london dispersion (Van Der Waals) forces?
In a nonpolar covalent bond, we expect the electrons to be equally shared between the atom's electronegativities are the same. But, even though the electrons aren't actively being pulled to one atom, they can still randomly assort themselves in the orbital in such a way that one atom has a little tiny bit more electron density than the other one. This results in a spontaneous, very short lived, very small dipole. The negative end of this temporary dipole will attract to the positive end of some other molecule's temporary dipole. This low-level but ever present attraction between the spontaneous dipoles of non-polar compounds is referred to as London Dispersion Forces, and is the weakest of the intermolecular forces.
How do we determine the limiting reactant?
In a reaction with two reactants, you can convert the moles of one reactant into the moles of another reactant using normal stoichiometric methods. So what you do is... 1. Identify the moles of both reactants. 2. Pick one of the reactants, it does not matter which. 3. Use the balanced equation to convert the moles of the reactant you picked into the moles of the other one. 4. Now compare the converted moles of the reactant to the original mole of the other reactant. The smaller number is the limiitng reactant.
How are redox titrations similar to acid-base titrations?
In acid base titrations, the pH and thus the transfer of protons is what is used to reach the equivalence point of the reaction. In a redox reaction, the E cell of the reaction and thus the transfer of electrons is what is used to reach the equivalence point of the reaction.
How do reactions respond to changes in temperature as described by Le chatelier's principle?
In an endothermic reaction, heat is a reactant, so increasing the temperature shifts the equilibrium right. On the other hand, in an exothermic reaction, heat is a product, so increasing the temperature shifts the equilibrium left.
What is an overtone?
In an object that produces multiple frequency waves when struck, the overtones are the higher frequency waves.
"Characteristics of Solids "
In compressible. Have very little free space in between them. Sound travels fastest in this medium due to the efficient E transer since the molecules are so close.
What does it mean to be axial or equatorial?
In cyclic molecules, substituents can either be axial (perpendicular up or down) or equatorial (sticking out up or down). As you can see from the picture, both the axial and equatorial positions alternate their direction around the ring. Starting from the top left carbon, the axial bonds go Up, Down, Up, Down, Up, Down. Starting from the top left carbon, the equatorial bonds go Down, Up, Down, Up, Down Up.
What is a limiting reagent?
In every reaction the reactants react in some ratio to make products. For example, two reactants might react 1:1 to make a product. In the case of 6 Weiners and 5 Buns reacting in a 1:1 fashion, the first reaction would leave 5 Weiners, 4 Buns, and 1 product Hotdog. This will continue until there are 0 Buns left, 1 Weiner Left, and 5 HotDogs Notice how, even though there were 6 Hot Dogs worth of Weiners, only 5 Hot Dogs were made. This is because there were only 5 Hot Dogs worth of Buns. The reactant that runs out first and defined the yield of the reaction is the limiting reagent. In this case, the Buns would be the limiting reactant.
Other than being used as leaving groups, how are tosylates and mesylates useful?
In oxidation reactions, alcohols can be oxidized even if you don't want them to be. Converting to Tosylate or Mesylate protects the alcohol from oxidation, so you can convert, oxidize the molecule the way you actually want to, then convert the tosylate or mesylate back into an alcohol. Be careful though, tosylates and mesylates are good leaving groups so make sure you don't accidentally performe a substitution reaction and knock them off.
Describe a simple distillation?
In this method, a distilling flask is filled with a solution of mixed liquids. The distilling flask is connected to a distilling column, which is a condenser and a thermometer. The distillation column is connected to a receiving flask. The distilling flask is heated until one of the liquids boils out. As the one liquid boils, it rises up as vapor. At the top of the flask the vapor will condense. Some of the liquid will fall back down into the flask, but most of it will get trapped in the condenser which sends it to the receiving flask, where it is collected in pure form as distillate.
Describe the production of an Imine
In this reaction, an ammonia molecule serves as a nucleophile and attacks the carbonyl carbon. The oxygen picks up two hydrogens to become water. The attached amino group uses its free electrons to generate a double bond with the carbon, which kicks of the water leaving group. Finally, the double bonded amino group loses a proton to reduce its formal charge and increase the stability of the molecule, resulting in an imine.
"Characteristics of Liquids "
Incompressible. Fit the shape of the container. Liquids distrubte evenly. Decreasing the pressure will cause the liquid to evaporate due to the kinetic energy of the molecules. Decrease P
What is Infrared Spectroscopy?
Infrared Spectroscopy is a type of spectroscopy that uses IR light to measure the molecular vibrations in different moieties. In this method, IR light is passed through a sample and the amount of absorbed light is measured. Specific bonds have specific energy light associated with them, so we can use IR spectroscopy to determine the bonds in a compound.
What is inorganic phosphate?
Inorganic phosphate is just a term used to describe phosphate molecules in biological systems. It is denoted with Pi.
What is integration in the context of NMR?
Integration is when you take the area under the curve, which is kind of like saying how big it is. The integration values are arbitrary, but they will relate to one another in the same ratios that the protons relate to one another. For example, in the NMR below, there are 3 b hydrogens and only 1 a hydrogen. If you were to take the integral of both the b and th a curve, you would find the ratio to be 3:1.
How is the amplitude of a sound wave related to its intensity?
Intensity increases proportional to the square of the amplitude. This means that, if you double the amplitude, you will quadruple the intensity.
How is intensity of sound related to your distance from it?
Intensity of sound is inversely proportional to the square of the distance. This means that if you are twice as far away from a sound, it will be 1/4 times as intense. If you are 3 times as far away from a sound, it will be 1/9 times as intense.
What is Internal validity?
Internal Validity refers to whether or not you actually identified causality in a study between the independent and dependent variable.
What are intramolecular forces?
Intramolecular forces are strong electrostatic interactions between the atoms within a molecule, i.e. the actual bonds in the molecule.
What happens to an ionic compound when you dissolve it?
Ionic compounds will split into their consituent cations and anions when they dissolve.
What special case must we remember when considering Ionization energy?
Ionization energy increases massively once the atom has an octet. This is because a full octet is very stable and it takes a lot of energy to knock an electron out of an octet. Example of this phenomenon shown below.
What is Ionization Energy?
Ionization energy is the energy required to remove an electron from a sample of gaseuos atom. The greater an electron's effective nuclear charge, the stronger the nucleus holds the electron, and therefore the higher its ionization energy.
What are the units of rate constant?
It depends. Each reaction can have different rate constant units, and the MCAT can even ask you about this specifically. You can always figure out the units of a rate constant given the reactants. This is because you know that the rate will have units of Ms-1 and any reactant will have units of M. Just use dimensional analysis to determine the units of rate constant.
How does the spontaneity of a reaction relate to its speed?
It doesn't! Kinetics is entirely separate from Thermodynamics. For example, there are reactions that are non spontaneous that go very fast once they are started, and there are reactions that are spontaneous that go very slowly until they finally reach completion.
What is the energy barrier?
Just another term for Activation Energy, Ea
What is a dielectric material?
Just another way of saying insulator.
How are esters named as substituents and parent chains?
Just like with carboxylic acids, esters won't ever really be a substituent, they'll usually be the parent chain. But, in those rare cases where this isn't true, esters substituents are given the name alkoxycarbonyl- There are two terms to an ester parent name. The second term is the parent chain with the ester, and it is named by dropping the -oic acid and replacing it with -oate. The first term is the name of the group to which the ester is bonded.
What is the naming convention for 5 and higher carbon molecules?
Just use the normal greek roots for numbers. 5. Pent 6. Hex 7. Hept 8. Oct 9. Non 10. Dec 11. Undec 12. Dodec Etc.
What is kinetic friction?
Kinetic friction is the force that acts between two objects sliding against each other.
Of the two, which is made faster, kinetic product or thermodynamic product?
Kinetic product is made faster.
What is laminar flow?
Laminar flow is smooth and orderly flow. It is usually represented as parallel layers of fluid flowing smoothly over one another.
What is log?
Log is a mathematical operator. When you log a number, you are saying, "What number, Y, would I have to raise my base, A, to in order to get this number, X. logA(X) = Y For example, log2(4) = 2. Because I would have to raise my base, 2, to the power of 2, in order to get the number I am logging, 4. For another example, log3(9) = 2. Because I would have to raise my base, 3, to the power of 2, in order to get the number I am logging, 9.
What is the log of any base of 1 equal to?
Log of any base of 1 is equal to 0. This is because any number raised to the 0 will give you 1.
How do we visually determine the harmonic of a string attached at both ends?
Look at the number of Antinodes
How do you determine the number of valence electrons an atom has?
Look at the periodic table and determine which column the atom is in. (the numbers above the periodic table are the number of valence electrons. The noble gases can be thought of as having 0 valence electrons or 8 valence electrons.)
How can one determine how much of a floating object lies beneath the surface of the water in which it is floating?
Look at the specific gravity. The specific gravity will be equal to the percentage of the object that is submerged. For example, an object with a specific gravity of .92 will float with 92% of its volume submerged in the water. Objects with a specific gravity of more than 1 sink in water and are therefore completely submerged. po/pw=%submerged
What do we do if we are working with a lewis structure and seem unable to get a stable octet on all the atoms?
Make sure that one of the elements you are working with isn't an exception to the octet rule. For example, remember some elements can handle less than 8 electrons, and every element in period 3 or larger will be able to hold extra electrons in their d orbitals.
What is a mass spectrometer?
Mass spectrometry involves firing molecules of varying weights through a circular tube and a magnetic field. The higher the molecule's weight, the less it is deflected by the magnetic field. The lower the molecule's weight, the more it is deflected by the magnetic field. We can use the differences in their deflection to separate molecules and identify them individually.
What is mechanical advantage?
Mechanical advantage is the ratio of magnitudes of the force exerted on an object by a simple machine to the force actually applied to the simple machine.
How does mechanical advantage work?
Mechanical advantage is when we use a machine of some sort to reduce the amount of force needed to achieve some outcome. This reduction in force is accomplished through an increase in distance through which the force has to be applied, thus conserving energy. MA=Foutput/Finput
What is median?
Median is the absolute midpoint of the data. This is determined by listing all the data in order of increasing value and determining the absolute middle data point.
What is molar mass?
Molar mass is how much mass you will have of something given a mole of it. It is usually expressed in g/mol
What is molarity, M?
Molarity is the amount of moles of solute in some amount of liters of solution.
What is Molecular Geometry and how do we predict it with VSEPR?
Molecular geometry is the geometry of the molecule as it pertains to the bonds it makes with other atoms. Because there is a distinction here between bonded electrons and nonbonded electrons, we must count them up seperately and then refer to VSEPR Theory for the shape.
What is spectroscopy?
Molecules of different types have different energy states which are associated with certain types of rotation, vibration, electron absorption, and nuclear spin transitions. Depending on the molecule, it will have different energy states. A molecule can be promoted to a higher energy state by shining light of the correct energy (frequency) on it. The molecule will spontaneously revert back to a lower energy state, releasing that same light. We can shine light of different kinds on chemicals and see what kind of light we get back to determine the identity of the molecule. This is the fundamental principle behind spectroscopy.
When a molecule has resonance structures, which of its resonance structures will it behave like?
Molecules with resonance structures will behave as though they were resonance hybrids, that is to say, the hybrid structure of all the resonance forms combined. Some resonance structures are more stable than others (this can be determined with formal charges), and therefore will dominate the overall resonance structures. In these cases, the molecule will act mostly like the dominant resonance structure, but will still have small characteristics of the other resonance structures.
What is the Arrhenius Equation?
NOTE: It is more important you understand the relationship between these variables. It is unlikely you will have to calculate using the Arrhenius Equation. The Arrhenius Equation is a rigorous equation that gives the rate constant for a reaction given various variables. Where k is the rate constant of the reaction, A is the frequency factor, e is the natural base, Ea is the activation energy of the reaction, R is the ideal gas constant, and T is the temperature.
When placing substituents names before the parent name with prefixes, do we consider those prefixes for alphebatization?
No! di-, tri-, etc. are not used in alphebatization. This means that Ethyl- would come before di-methyl, because E comes before M and we ignore the D of the prefix. This rule applies to the hyphenated prefixes like n- and tert- as well. This rule does NOT apply to the non-hyphenate prefixes like iso, neo, and cyclo.
Does the path taken from one equipotential line to another matter?
No, any path from equipotential line to another will take the same amount of work.
Are all resonance structures created equally?
No, certain resonance structures will be much more stable and dominate for that reason. If one resonance structure is way more stable than the other, the molecule might be 99.9999% like the more stable resonance structure with a little tiny bit of the other resonance strucure contributing. Things that make a resonance structure more stable include: Some resonance structures will have less formal charge on the atoms, which is more stable. Some resonance structures will have more full octets or full octets on highly electronegative atoms, which is more stable.
Do we see geminal diols often?
No. Geminal diols spontaneously dehydrate to produce carbonyl compounds.
Is the equilibrium constant a constant?
No. The equilibrium constant is different for every reaction and is different at evey temperature.
Do the stoichiometric coefficients of a balanced reaction tell you the orders of the rate law?
No. The stoichometric coefficients rarely have anything to do with the order of rate law. There are only two very rare cases when the stoichiometric coefficients tell you the order of the rate law. 1. If the reaction mechanism is a single step and the balanced overall reaction is reflective of the entire chemical process 2. When the complete reaction mechanism is given, the orders of the reactants will be equal to the stoichiometric coefficients of the slowest step, assuming there is no intermediate in the slowest step.
Is a reaction always spontaneous?
No. reactions can have different spontaneities at different temperatures. You can always check to see if a reaction will be spontaneous or not at a certain temperature by using the gibbs free energy equation.
What is noise?
Noise is defined scientifically as the sound you hear when an object vibrates at multiple frequencies that have no relation to one another.
What are non-conservative forces?
Non conservative forces dissipate energy into the form of heat/light/sound. e.g. Friction, air resistance, etc.
What are the general characteristics of non-metals?
Non-metals are usually brittle solids with no luster or gases. Non-metals are also poor conductors of heat and electricity.
What is Normality?
Normality is equal to the number of equivalents of interest per liter of solution. An equivalent of interest is a measure of the number of molecules there are to react. To calculate the normality of a solution, you must know what purpose the solution serves and which species is the reactive species. Then, the normality will equal the molarity of the reactive species multiplied by the number of times it could react. For example, H2PO4 could dissociate twice to give 2 protons into solution. This means, in a solution of base, it will be able to react with the OH groups not once but twice. Therefore, it's normality will be equal to twice it's molarity.
Is the rate constant a constant?
Not really. It needs to be experimentally determined for every reaction. But, if you are given the rate constant for a reaction and it matches the conditions of your reaction, you can use it like a constant in the rate equations.
As the charge separation of a cation and an anion increase, {{c1::Ionic Bond strength increases::what kind of intermolecular force increases?}}
Note, the lattice energy getting more negative means that the lattice is more stable, meaning it is comprised of stronger ionic bonds.
What happens if a molecule hits another molecule with less energy than the activation energy of the reaction?
Nothing will happen. If the reaction is to occur, the activation energy must be surpassed.
How does one calculate the weight of a given volume of a substance?
Notice that, if you multiply density by volume, you will get mass, at which point this equation simplifies to the hitherto described equation Fg=mg. Therefore, this equation is actually just a combination of the known force of gravity equation and the equation to calculate density.
What types of nuclei are NMR active?
Nuclei with odd mass numbers, odd atomic numbers, or both will haave a magnetic moment when placed in a field. This means that 12C, for example, is not NMR active.
How do you name cis- and trans- on rings?
On a ring, substituents can either be on the same side or on opposite sides of the ring. These molecules are geometric isomers to one another, and must be able to be identified. If the substituents are on the same side of the ring, the molecule is given the suffix cis- If the substituents are on opposite sides of the ring, the molecule is given the suffix trans-
Describe the formation of acetals or ketals from aldehydes and ketones respectively
Once a hemiacetal or hemiketal is formed, the hydroxyl group is protonated and leaves as a molecule of water, forming a carbocation (Sn1 Mechanism!!). At this point an alcohol molecule attacks, forming a ketal or an acetal depending on if the parent molecule was a ketone or an aldehyde.
What are the three rays that can be drawn in order to use a ray diagram for mirrors?
One must draw at least 2 of the following in order to find the image. 1. A parallel ray that is reflected through the focal point. 2. A ray that passes through the focal point and is reflected parallel to the mirror. 3. A ray that passes straight through the mirror to the center of curvature and is reflected with an angle equal to its incident. Rays 1 and 2 used below All 3 rays used below.
In what direction do frictional forces act?
Opposite that of the accelerating force.
What is optical activity and what are the two types?
Optical activity refers to the rotation of plane-polarized light by chiral molecules. Enantiomers will rotate plane polarized light the same magnitude, but in opposite directions. A molecule that rotates plane polarized light to the right aka clockwise, is dextrorotary (d-) and is labeled (+). A molecule that rotates plane polarized light to the left aka counterclockwise is levorotary (l-) and is labeled (-).
What is the Aufbau Principle?
Orbitals are filled in order of lowest energy to highest energy. The order of low energy orbitals to high energy orbitals can be determined using the diagonal method shown below. An electron not in its lowest energy orbital is called excited and will shortly return to its lowest energy orbital.
Which kinds of organic compounds are likely to be colored?
Organic compounds with conjugated double bonds or aromatic ring systems.
What is Osmotic Pressure?
Osmotic pressure is the "sucking" pressure generated by solutions that draw water into themselves because of the concentration gradient.
What kind of liquids exhibit osmotic pressure?
Osmotic pressure is the pressure associated with concentration gradients of solutes. Therefore, any fluid with dissolved solutes will exhibit osmotic pressure. It opposes osmosis
What is osmotic pressure?
Osmotic pressure is the pressure associated with concentration gradients. Think about it. When solutes go from high concentration to low concentration, what makes them move? It's osmotic pressure that makes them move!
What does it mean for two waves to be out of phase?
Out of phase waves have a phase difference that is not equal to 0 degrees.
What is an oxidation state?
Oxidation state is the charge an element will usually take if it is going to form an ion and become part of an ionic compound. For most elements, this will be the charge assocated with an octet configuration. For example, all of the Alkalie Metals (Na, K, Li) will always have an oxidation state of +1 in ionic compounds. The same is true for some Halogens and their -1 oxidation state. Then, there are some elements that are usually going to have the oxidation number associated with their octet configuration, but not always. Finally, there are the transition metals, many of which take on many different oxidation states. It is important to know the few stable transition metals and then just figure out what the oxidation state of any other transition metal is during the problem.
In organic chemistry, what is a quick way to determine whether or not a molecule was oxidized or reduced?
Oxidized molecules are molecules that have bonds to oxygen, carbons, nitrogens, or halides (heteroatoms). Reduced molecules are molecules that have bonds to hydrogen. If a molecule undergoes a reaction and afterwards it has more bonds to hydrogen than to heteroatoms, it was probably reduced.
What is the ideal gas law?
PV=nRT where P is the pressure , V is the volume, n is the moles of the gas, R is th ideal gas constant (.0821) and T is the temperature.
What is a partition coefficient?
Partitioning is the equilibrium of a molecule between the mobile and stationary phases in a chromatograph. Therefore, the partition coefficient is like the equilibrium constant for a molecule to be associated with the mobile phase and the stationary phase. The lower the partition coefficient, the faster the molecule elutes.
What are dipole-dipole interactions?
Polar molecules share electrons unequally in their bonds, and therefore have areas of partial negative charge and areas of partial positive charge. In dipole dipole interactions, the positively charged region of one molecule will attract to the negatively charged region of another molecule. These dipoles are not temporary, like in London Dispersion forces, and so the dipole-dipole interaction is much stronger.
What is polarity?
Polarity is a phenomenon that occurs when two atoms have a difference in their electronegativity. When these atoms come together, they share the electrons like in a normal covalent bond, but one of the atoms pulls the electrons harder and sort of hogs them. They're still shared, but not 50/50. The new ratio might be 20/80. The presence of more electrons on one atom will establish a slight negative charge there. On the other hand, the presence of less electrons on the other atom will establish a slight positive charge there. Polarity is the term used to describe how unequally shared the electrons are in the bond and how large the partial charges on the atoms are because of the unequal sharing of electrons.
Angular Momentum
Product of rotational inertia and rotational velocity. L=Iw - more inertia lower velocity. If you decrease radius you will increase speed.
What side of the reaction is heat on in an exothermic reaction?
Products side.
What is radiation?
Radiation is the transfer of energy by electromagnetic waves. Radiation is unique in that it requires no contact whatsoever with a material to exert its effects. In fact, radiation can even transfer energy through a vacuum. When the particles accelerate they begin to release electromagnetic radiation through the high E electrons causes radiation to release. EX: Seeing a light from a fire is EM radiation.
What is the purpose of randomization?
Randomization is used to separate groups without bias. You can randomize trials in many different ways, but fundamentally you need to make sure it's not a person picking the groups.
What is raoult's Law?
Raoult's law mathematically describes vapor point depression. It is equal to Pa=XaPao where Pa is the vapor pressure of solvent A when solute is present, Xa is the mole fraction of solvent A in the solution, and Pao is the vapor pressure of solvent A in its pure state.
What are reaction diagrams?
Reaction diagrams are graphs that track a thermodynamic property of a reaction over time. These graphs usually measure free energy change with respect to coordinate, enthalpy change with respect to coordinate, or entropy change with respect to coordinate.
What are real gases?
Real gases are the gases that actually exist in the universe. These are different from ideal gases in that they occupy volumes and exhibit intermolecular forces.
What is recrystallization?
Recrystallization is a method for further purifying crystals in solution. In this method, we put our product in a small amount of solvent so that it is close to dissolving, but not quite there yet. Then, we slowly heat the solvent, which increases the solubility enough to make the product dissolve. Finally, we slowly cool the flask, which causes the product to slowly crystalize out of the solution on its own with no impurities.
What is reflection?
Reflection is the tendency of a wave to bounce backwards when it encounters a boundary between two media. These media can be anything as long as they are different, oil and water, air and glass, etc.
What is relative configuration?
Relative configuration is the configuration of a chiral molecule as it relates to another molecule. It doesn't tell you something specific to the molecule, instead it tells you how it is different from some other molecule. Examples of relative configurations include: saying something is an enantiomer of something else, saying something is a diastereomer of something else, etc.
How do we use dimensional analysis to convert things?
Remember, dimensional analysis is just recognizing the basic quantity associated with the number and the specific unit of measure associated with the number. Once we see the basic quantity and the unit of measure, we can combine it with a conversion factor to convert it into a different unit of measure (but never a different basic quantity). These conversion factors must be memorized and then combined used in such a way so as to cancel out the starting unit of measure and result in only the new unit of measure.
What is meant by ideal bond angle?
Remember, each atom in a molecule has positive and negative charges associated with it. This means that, certain arrangements of the atoms will result in higher/lower electrical potential energies. The molecule will always adopt the most stable configuration, which is the configuration with the least amount of electrical potential energy. This most stable configuration is described by the ideal bond angle. For example, in a molecule with 4 bonded pairs and no unbonded pairs, the lowest potential energy is associated with all the atoms being arranged in a tetrahedron, which has an ideal bond angle of 109.5
How do we name ionic compounds?
Remember, ionic compounds will always have a cation and an anion. 1. Write the cations name as is (Unless it is an element that can form more than one stable positive ion, in which case you denote what its charge is with parentheses and roman numerals. 2. Write the anion's name. If it is a monoatomic (One type of atom, O2-, F-) anion drop the ending of element and add -ide. If it's a polyatomic ion, just write the polyatomic anion's memorized name.
How does one determine whether an atom's ion will be bigger or smaller?
Remember, the electrons are what determine the overall size of the atom. Therefore, if an atom loses electrons to become an ion (like the metals), it will have a smaller ionic radius than atomic radius. On the other hand, if an atom gains electrons to become an ion (like the non-metals), it will have a larger ionic radius than atomic radius.
Amides, Esters, and anhydrides are produced from by {{c1::condensation::condensation or decomposition}} reactions?
Remember, these molecules are produced by bringing together two molecules and losing a small one, in the case of these reactions,the small molecule lost is water.
How does resonance affect molecules?
Resonance spreads electrons out, which reduces the internal repulsion of a molecule, which makes it much more stable! This phenomenon is very powerful and actually has its own name, resonance stabilization.
What is resonant frequency?
Resonant frequency is the natural frequency or frequencies at which an object vibrates. Any solid object, when hit, struck, rubbed, or disturbed physically in any way, will begin to vibrate. Applying a forced frequency to match an objects natural frequency. This can cause a forced osicllation and vibrate at max amplitude. This can also cause a object to shatter.
What is ring strain?
Ring strain is the instability introduced into a molecule by the formation of a ring. It has its own name, but its really just a combination of angle, torsional, and steric strain that occurs when you cyclize molecules in certain ways. For the figure below, remember more energy means more unstable.
What is STP?
STP is standard temperature and pressure. It refers to conditions of 273 K (0C) and 1 atm. Note this is not the same thing as standard conditions!
How do secondary alcohols interact with oxidizing agents?
Secondary alcohols interact with all oxidizing agents to produce Ketones.
What is a semilog and log-log graph?
Semilog and log graphs make nonlinear data linear by messing with the scale of the axes. In a semilog plot, one of the axes is represented as orders of magnitude of 10. In log-log graphs both axes are represented as orders of magnitude of the same base, usually 10. Watch out for these graphs on test day! The axes are important.
What is shielding?
Shielding refers to how much electron density is on a proton. Generally, the less shielding, the farther the chemical shift associated with that proton. This means hydrogens attached to or adjacent to electronegative atoms usually have higher chemical shifts. MNEMONIC: Deshielding moves the proton Downfield (to the left)
Describe the relative strength of sigma bonds compared to pi bonds.
Sigma bonds, because they are a product of actual overlap between atomic orbitals, are much stronger than pi bonds. Note, a double bond is stronger than a sigma bond because a double bond has a sigma bond AND a pi bond, but the sigma bond is still providing most of the bond energy.
What is the solubility product?
Solubility product is just a special form of an equilbrium constant. It describes the equilibrium of a solid dissolving into its constituent ions. You find it using the normal rules for equilibrium expressions.
What are the two components of a solution?
Solute and solvent
How do solutes affect vapor pressure?
Solutes depress the vapor pressure.
What is specific rotation?
Specific rotation is the amount a compound rotates light per concentration of the molecule and length of the tube through which the light passes.
What is spin-spin coupling?
Spin-spin coupling, aka peak splitting, is a phenomenon seen when nonequivalent protons are attached to adjacent carbons. Depending on the number of adjacent carbon bound hydrogens, peaks will be split up into pieces.
How does one approach a projectile motion problem?
Split all motion into x and y components.
How does one calculate the magnitude of a vector from its components?
Square both component vector magnitudes, add them, and square root the sum.
What does it mean to have a staggered newman projection?
Staggered newman projections occur when the substituents are not lined up with one another. These can either be in anti or gauche conformation.
What is standard deviation?
Standard deviation is a number that bsically tells you how spread out the data is. The more spread out the data, the higher the standard deviation.
In closed pipes, what harmonics are standing waves limited to?
Standing waves in closed pipes are limited to odd harmonics. This is because the standing wave in a closed pipe has to have a node at one end and an anti node at another end, and this is only possible with odd harmonics.
What is a static equilibrium?
Static equilibrium is when the reaction is at equilibrium because neither the forward nor the reverse reaction are occuring at all.
"Hooke's Law "
Stress causes Strain (Pressure causes change). As long as the stress is not too large then stresss and strain are proportional. Stress= modulus * strain F=-kx
How can we find the enthalpy of a reaction?
Subtract the enthalpy of the products by the enthalpy of the reactants.
How can we calculate the standard gibbs free energy for a reaction?
Subtract the sum of the standard gibbs free energy of the products by the sum of the standard gibbs free energy of the reactants.
What is superheating?
Superheating is when a liquid is heated to a temperature above its boiling point without vaporizing. Superheating occurs when gas bubbles within a liquid are unable to overcome the combination of atmospheric pressure and surface tension. This is fixed in distillations by adding boiling chips, ebulliators, or magnetic stir bars to the distilling flask.
What is the purpose of TMS?
TMS is used to standardize NMR spectra. TMS will always be calibrated to be equal to 0 ppm. When counting peaks to determine the number of hydrogens in a molecule, skip the TMS peak because its just the standard.
What does it mean for energy in this universe to be quantized?
That the energy in this universe is quantized means that the energy only comes in discrete packets, of which you can have only whole number values. For example, energy is like children. You can either have 2 or 3, you cannot have 2.5.
What are the 2 special d-orbital modifications we must make to the electron filling order?
The 2-special cases of electron filling exist for the Chromium group of elements (Chromium and all the elements below it on the periodic table) and the Copper group of elements. For these elements, instead of taking on a normal 4s23d4 configuration, they will take a 4s13d5 configuration. This is because filling the 3d orbital up with 5 electrons (half) provides the atom with extra stability. So much extra stability, that the atom will pull an electron from the s orbital to fill the d orbital. The same thing happens for the copper elements, only the d orbital electrons go from 9 to 10 instead of 4 to 5. For example, Copper's electron configuration is actually 4s13d10 instead of 4s23d9
What is the SI unit of pressure?
The Pascal (Pa)
What is the Pauli Exclusion Principle?
The Pauli exclusion principle says that no two electrons in a given atom can posess the same set of four quantum numbers. Specifically, this means that electrons in the same orbital must have opposite spins in order to be unique.
What is the effective nuclear charge?
The actual attraction that outer electrons feel from the nucleus when you account for shielding.
What is the adsorbent?
The adsorbent is just another word for the stationary phase in a chromatograph.
Describe the second step of the Strecker Synthesis
The aminonitrile generated in the first step is protonated to activate it for nucleophilic substitution. Next, a water molecule attacks the nitrile group to form an Imine. The attached water deprotonates to an alcohol and transfers the proton to the imine, activating it for another substitution by water. The second water attack results in a compound with a water, alcohol, and amino group on the same carbon. The attached water deprotonates to an alcohol and transfers the proton to the amino group, activating it as a leaving group. One of the hydroxyl groups forms a carbonyl and kicks the amino group off. The Carbonyl deprotonates, resulting in an amino acid.
What is the axis in the context of optics?
The axis is the normal line that passes through the center of the mirror or lens.
What are the characteristic physical properties of aldehydes and ketones?
The carbonyl carbon contains a decently strong dipole due to oxygen's higher electronegativity when compared to carbon. This results in increased intermolecular forces, which leads to higher boiling points and melting points. However, because there is no hydrogen on the oxygen, aldehydes and ketones can interact through hydrogen bonds with themselves, which means there intermolecular forces aren't as high as alcohols and carboxylic acids. Aldehydes and ketones are polar, but not that polar, so their solubility in water is variable depending on how long the carbon chain is. Of the two, aldehydes are generally the better electrophiles.
How can you generally describe the reactions of aldehydes and ketones?
The carbonyl carbon is a good electrophile, so most of the reactions involving aldehydes and ketones involve nucleophilic substitution at the carbonyl carbon. The bond to the nucleophile displaces one of the bonds to the oxygen and pushes it up as a lone pair on the oxygen.
What does it mean if a thermodynamic property is written with a degree sign (prime) or called "Standard"
The changes in enthalpy, entropy, and free energy that occur when a reaction takes place under standard conditions are called the standard enthalpy, standard entropy, and standard free energy changes, respectively, and are symbolized by ΔH°, ΔS°, and ΔG°.
What determines the color of an object?
The color of light that the object reflects back into your eye. In other words, an object will appear to be the color it does NOT absorb. For example, red apples absorb every color EXCEPT for red, which just bounces off the apple and into our eye.
What is the critical point?
The critical point marks the boundary of pressure and temperature at which you will still see normal phases. After the temperature and pressure exceed that of the critical point, the substance becomes a supercritical fluid with gaseous and liquid properties.
What is the Junction Rule?
The current going into a junction must be equal to the current going out of a junction.
What part of the reaction diagram corresponds to the activation energy of the reaction?
The difference in energy between the reactants and the transition state corresponds to the activation energy.
What happens when two liquids at different temperatures mix?
The energies of the liquids will be added together and distributed evenly to the total mixture. Basically, the total energy will be the same before and after.
What do rows allow us to easily ascertain?
The energy level at which the element's valence electrons reside.
What does the principle quantum number represent?
The energy level in which the electron resides.
What is the nth ionization energy?
The energy required to remove the nth electron from a gaseous sample of the compound in question. For example, the first ionization energy is the energy required to remove the first electron from an atom. The 4th ionization energy is the energy required to remove the fourth electron.
How does one find the enthalpy of a reaction using only bond dissociation energies?
The enthalpy of the reaction will be equal to the energy it absorbed by breaking bonds minus the energy it released by forming bonds.
What is the third law of thermodynamics?
The entropy of a perfectly organized crystal at absolute zero is zero. This really means that there can be no temperature lower than absolute zero.
What makes music sound like music and not like noise?
The fact that the multiple frequencies at which the object vibrates are related to eachother by whole number ratios instead of just being randomly related.
What is the focal point?
The focal point is the point at which light rays parallel to the mirror or lens are focused (or virtually focused in the case of negative focal lengths)
How does one calculate the position of the focal point?
The focal point will always be half the distance of the radius of curvature. R/2
What is the purpose of the four quantum numbers?
The four quantum numbers exist so we can quickly and easily describe every electron's position in the atom. For example, if I assign the quantum numbers 2, 0,0,1/2, I know exactly which electron I am talking about: the electron in the second energy level, in the s orbital, in the up spin configuration.
What is the standard enthalpy of combustion?
The heat associated with combusting something at standard conditions under constant pressure.
What is enthalpy of fusion?
The heat associated with fusion (going from solid to liquid) under constant pressure.
What is the enthalpy of vaporization?
The heat of vaporizing (going from liquid to gas) at a constant pressure.
What is the Ion Product (IP)?
The ion product is the state of the dissolving equilibrium at any given point. It can be compared to the ksp to determine whether or not the solution will precipitate. It is calculated in the same manner as Ksp.
What is the kinetic molecular theory?
The kinetic molecular theory is a series of assumptions that is used to explain the behaviors of gases. These assumptions makes it possible to derive the ideal gas laws.
When using and analyzing newman projections, which substituents are the most important?
The largest ones. This is because we use the largest substituent's angle from one another to determine the conformation of the Newman Projection
What is cos theta equal to?
The length of the adjacent side of the angle over the length of the hypotenuse.
What is the absolute lowest dielectric constant and to what material does it belong?
The lowest dielectric constant is 1 and it belongs to vacuum, which is when there is absolutely nothing between the plates of a capacitor. The dielectric constant for a material will ALWAYS be higher than this value, and never lower. There are no negative or less than 1 dielectric constants.
How can there be a range of static frictions?
The magnititude of static friction depends on factors like the amount of surface area in contact (more = higher).
What is the mode?
The mode is the data point that is represented the most in the data.
What is the molar solubility?
The molar solubility is the concentration of an ion in molarity in its saturated solution.
Why does surface tension occur at the surface?
The molecules in a liquid experience an attractive force with one another known as cohesion. Under the surface of the liquid, each molecule is completely surrounded by other liquid molecules. This results in the cohesion forces being felt in all directions, causing them to cancel out. At the surface, on the other hand, molecules are only experiencing cohesion forces from beneath them. This causes the molecules at the surface of the liquid to be pulled inward, leading to the tension force at the surface.
How do the moles of a molecule relate to the moles of the atoms that make it up?
The moles of a molecule are related to its subsitituent atoms by their subscripts. For example, one molecule of H2O is comprised of 1 oxygen and 2 hydrogens. Therefore, to make 1 mole of H2O I would need to collect 1 mole of Oxygen and 2 moles of Hydrogen, and combine them together to make 1 mole of H2O. Notice that there are 2 moles of Hydrogen in 1 mole of H2O because H2O explicitly calls for twice as many hydrogens than oxygens.
Describe the Hill Criterion of Consideration of Alternative Explanations?
The more plausible alternative explanations for a phenomenon, the less likely your explanation is right. On the other hand, if you can show that your explanation is the only plausible one and there aren't any other plausible explanations, your explanation is much more likely to be right.
Describe the Hill Criterion of Plausibility?
The more reasonable the mechanism of action between the independent variable and the dependent variable, the more likely they are actually causally related. For example you can get good correlations between ice cream sold and shark bites. But, just think about it, it is extremely unlikely that ice cream sales could be having an effect on shark bites. What is actually the case is that a confounding variable, in this case temperature (in the summer more people eat ice cream and more people go to the beach where sharks hang out.) is the more plausible explanation.
What is the natural log ln?
The natural log is just a log with a base of euler's number = e = 2.72
What is NMR spectroscopy?
The nucleus of an atom, when placed in a magnetic field, can be aligned with the magnetic field or unaligned. The difference in energy between these two states depends on the type of atom and the types of atoms around it. What we do is we put molecules in heavy magnetic fields and then shine different frequencies of light to see which ones they absorb. Depending on the types of absorptions we see in the NMR read out, we can determine the types of atoms in the molecule, and determine its overall structure.
What is a null hypothesis?
The null hypothesis is the hypothesis that two things do not influence one another at all. This is what we are trying to disprove when we do research.
What is the atomic number of an element equal to?
The number of protons in the element's nucleus
What is the rule that describes the way atoms join to form compounds and what does it state?
The octet rule. The octet rule states that to have a full octet of electrons in the outermost shell is the most stable state for an atom, and atoms will give/take/share valence electrons in such a way so as to ensure that both (or more) atoms in the compound have noble gas configurations
What is the overall order of a reaction?
The overall order of a reaction is just the sum of the orders of the individual reactants.
What is unique about the phase diagram for water?
The phase diagram for water has a negative slope for the solid<>liquid equilibrium line. This is out of the ordinary. Almost every phase diagram will only have positive slopes on its equilibrium lines. This is due to the hydrogen bonds in water and how they space out the crystalline structure of ice.
Describe the placebo effect?
The placebo effect is a phenomenon in which people observe or report changes despite the fact that they were given a fake intervention. This is a primarily psychological phenomenon, the mere expectation of results from the intervention produces them, even though the intervention itself doesn't. Often, negative controls are used to determine the magnitude of the placebo effect. The most common form of a placebo is a sugar pill that you give to people under the guise that it is a real drug.
What is a system in the context of thermodynamics?
The portion of the universe we are interested in observing or manipulating. The rest of the universe is the surroundings.
Explain how something like pressure is a state function.
The pressure in a system is defined only by the current equilibirum state of the gas particles. Take for instance, 2 balloons with a pressure of 1 atm each. The pressures in these balloons are identical. It does not matter if the first balloon came to 1atm from 10atm and the second balloon came to 1 atm from .01atm. The fact of the matter is that, right now, their pressures are both 1atm.
What is the principle of superposition?
The principle of superposition states that when waves interact with eachother, the displacement of the resultant wave will be equal to the sum of the displacements of the two interacting waves. This means waves add when they have the same sign and they subtract when they have opposite signs.
What is the radius/center of curvature for a spherical mirror?
The radius/center of curvature is the distance to the center of the theoretical sphere that the mirror would make if it was a complete sphere.
What is the range of data?
The range of a data set is simply the difference between the largest and smallest value. Range is heavily affected by the presence of outliers and is not a very good measure of distribution for this reason.
What is power? (No calculation, qualitative)
The rate at which energy is transferred from one system to another.
What is a rate determining step?
The rate determing step is the slowest step of the reaction mechanism because it acts like a kinetic bottleneck.
What is acceleration?
The rate of change of velocity m/s2
How do we calculate the rate of a reaction?
The rate will always be equal to the rate constant of the reaction times the concentration of the rectants raised to experimentally determined exponents.
What is the retardation factor?
The retardation factor, Rf, is a way of identifying a molecule after it has been TLC'd. The retardation factor is equal to the distance a certain molecule moved over the total distance the whole solvent moved. The Rf is relatively constant for a particular compound in a particular solvent, and can therefore be used as a reference to identify compounds.
Describe the Retro-Aldol Reaction
The retro-aldol reaction is just the reverse of the aldol condensation. In this reaction, aqueous base and heat is applied to an aldol. The result is that the bond between the alpha and beta carbon breaks, resulting in two carbonyl containing compounds.
How does one calculate the wavelength of the standing wave in an open pipe?
The same way you do it for a string, except both ends are anti nodes instead of nodes. Where L is the length of the pipe and n is a non-zero positive integer known as the harmonic.
What is the solvent?
The solvent is the component of the mixture that stays in the same phase after mixing. For example, water is the solvent because it was a liquid before mixing and after.
What is specific gravity?
The specific gravity of a substance is the ratio of the substance's density to the density of pure water at 1atm and 4 degrees celsius. These paramaters are chosen because pure water has a density of exactly 1g/cm3 at them.
How can we calculate the standard enthalpy of a reaction?
The standard enthalpy of a reaction will be equal to the sum of the standard enthalpies of formation for the products minus the sum of the standard enthalpies of formation of the reactants.
What is the standard enthalpy of formation?
The standard enthalpy of formation of a compound, Hfo is the enthalpy required to produce one mole of a compound from its elements in their standard states. For example, the standard enthalpy of formation of CO2(g) would be the enthalpy required to make one mole of CO2 from 1 mole of C(s) and 1/2 mole of O2(g)
How does one find the equivalent capacitance for capacitors in series?
The sum of the inverses will be equal to the inverse of the total capacitance.
What is an object's total mechanical energy?
The sum of the kinetic and potential energy (basically, the usable energy).
What are the symmetric molecular geometries and why are they important to know?
The symmetric molecular geometries are... 1. Linear 2. Trigonal Planar 3. Tetrahedral 4. Octahedral 5. Square Planar It is important to know these symmetric molecular geometries because their symmetry can cause their dipoles to cancel out. This means that, even if you have polar bonds in an atom, they could cancel out in a linear/trigonal planar/etc. configuration and result in a molecule that is, overall, non-polar.
Describe the tail to tip method?
The tail to tip method is a way of calculating the sums (or substractions) of vectors. Simply put the vectors tail to tip (flip the vector for negative)
What is absolute (hydrostatic) pressure?
The total pressure that is exerted on an object that is submerged in a fluid. For objects on planets with an atmosphere, the absolute pressure will be comprised of the pressure on the object from the liquid in which it is submerged and the pressure on the object from the atmosphere.
How does one separate a racemic mixture if the enantiomers have basically equivalent physical properties?
The trick is to react the racemix mixture with another chiral compound to make two different diastereomers. Think about it, let's say a racemix mixture is 50/50 the + and the - enantiomers. Well, if you react them with a + molecule, there will be two results, a molecule with both chiral centers + (+,+) and a molecule with one chiral center - and the other + (+,-). Diastereomers have different physical properties, and so from here you can separate the molecules using common lab techniques like crystallization, filtration, distillation, etc. Once you have both the diastereomers isolated, you take the diastereomer that has the enantiomer you want in it and run the original reaction backwards to regenerate the enantiomer you want.
Explain how something like work is a process function
The work done by or on a system is defined by the path the work took. Work can be calculated using W = F*d*costheta where F is force and d is distance. Therefore, differing path lengths (d) are built into the equation and must be considered. For further elaboration, consider the following. Two weights are at a height of 10 meters. The first weight was brought from 0 meters to a height of 10 meters, which took some amount of work. The second weight, on the other hand, went up 10 m, left 5 meters, and then right 5 meters. Both weights are in the same final position, 10 meters above ground level, but the second case took more work.
What is the work energy theorem?
The work energy theorem says that the total change in energy (work) of an object can be calculated by determining the change in an object's kinetic energy. Mechanical energy is conserved when external forces=0. Wnc=dKE+dPE When Wnc=0 Ei=Ef
What is the work function?
The work function is the amount of energy required to knock an electron off of the surface of a metal. This is similar to but not identical to ionization energy.
What is theoretical yield?
Theoretical yield is the maximum amount of product that can be generated according to the balanced equation. This number is the yield associated with 100% of the limiting reactant reacting, absolutely no side reactions of any kind occuring, and no accidental loss of product during collection.
What does it mean to be isothermal and how does that affect the first law of thermodynamics equation?
There is no change in temperature (and therefore no change in internal energy) Q=0 bc no change in temp
Of the two, which is more stable, kinetic product or thermodynamic product?
Thermodynamic product is the more stable of the two.
Ultimately, what determines something's solubility in a solvent?
Thermodynamics. If the electrostatic interactions between solvent and solute are favorable compared to the interactions between solute and solute, then the solvent will surround the solute and dissolve it.
How do the flow of electrons and current relate to one another?
They are opposite! The flow of electrons is opposite of the flow of current in an electrochemical cell.
What are the general characteristics of metals?
They are usually lustrous solid with high melting points. Metals also have the ability to be deformed without breaking (malleability and ductility). Finally, metals are usually good conductors of heat and electricity.
How do catalysts modify reaction diagrams?
They lower the activation energy by lowering the energy of the transition state.
Describe Thin Layer and Paper Chromatography
Thin Layer and Paper chromatography differ only in the stationary phase. In TLC, the stationary phase is silica gel or alumina. In Paper chromatography, the stationary phase is paper, which is composed of cellulose. In these methods, we take our mixed product and place it on the silica or paper plate. This is called spotting, because you just make a little spot. The plate is then treated with a solvent of some sort. The solvent is the mobile phase. Generally speaking, the plates are stood upright, and capillary action pulls the solvent up the plate. The mobile phase will pull the various molecules in the spot up the plate at different rates, and as long as the rates are different enough, the samples will separate.
What kinds of molecules make good reducing agents?
Things that oxidize well (i.e. try to lose electrons).
How do you approximate the value of a non-perfect square?
Think of the two surrounding perfect squares and estimate the value based on which perfect square the number you are squaring is closer to. We would expect the answer here to be a little above 4, because 18 is a little above 16. We would expect the answer to be even less less than 5, because 18 is even less than 25.
Anti Bonding orbitals are {{c1::higher::higher or lower energy?}} than bonding orbitals
This also means they are less stable!
Describe the Hill Criterion of Experiment?
This criterion states that if you really want to determine a causal relationship, you need to use an experiment.
Describe the Hill Criterion of Coherence?
This criterion states that the general body of scientific knowledge is pretty accurate, and if a causal relationship is claimed that is consistent with and fits well in the modern understanding, it is more likely to be a true causal relationship.
Describe the Hill Criterion of Dose-Response Relationship
This criterion states that the more an increases in the independent variable increases the dependent variable, the more likely the independent variable is causing the dependent variable.
Describe the Hill Criterion of Specificity?
This criterion states that the more specific the dependent variable is in regards to the independent variable, the more likely they are causally related. For example, if the dependent variable only ever changes when I change the independent variable, they are very likely to be causally related. However, if I can change the dependent variable by changing 10 other variables, then it is way less likely that the independent variable and the dependent variable are causally linked.
Young's Modulus
This is a constant of proportionality that is dependent on stress and strain. Essentially it tells us how resistant it is to stress or strain. This depends on type of material made. More IMF bigger modulus. EX: steel is wekear when subjected to shear forces vs tension and compression
All L-amino acids have (S) configurations except for {{c1::cysteine::which amino acid?}}
This is becasue the Sulfur in Cysteine's side chain flips its priority around. Try it yourself!
Sn1 reactions result in {{c1::racemix mixtures::inversion of stereochemistry or racemix mixtures?}}
This is because the carbocation is a trigonal planar intermediate, and the nucleophile can either attack it from the top or the bottom, resulting in two different stereochemistries.
Swapping two pairs on a fischer projection will {{c1::retain the stereochemistry::how is the sterochemistry affected?}}
This is equivalent to rotating the fischer projection 180 degrees.
What is a tosylate?
Tosylates contain the functional group -SO3C6H4CH3. Tosylates are good leaving groups. Tosylates are prepared by reacting alcohols with p-tolouenesulfonyl chloride.
What are the tenets of Transition State Theory?
Transition State Theory states that when molecules collide with energy equal to or greater than the activation energy, they form a transition state in which the old bonds are weakened and the new bonds begin to form. The transition state then falls apart into the products.
How are alcohols commonly modified to make them better leaving groups?
Treatment with acid to protonate the alcohol makes it a better leaving group. Conversion of the alcohol to a Mesylate or a Tosylate make it a better leaving group.
Describe Ultraviolet-Visible Spectroscopy?
UV-vis spectra are obtained by passing utraviolet and visible light through a sample in an inert non-absorbing solvent. The absorbance of the light at various wavelengths is recorded. UV-vis light is used to promote electrons to higher orbitals, and so based on the absorbance of certain types of UV-vis light, one can glean information about the molecules electronic structure.
What is ubiquinone?
Ubiquinone is a biologically important quinone. It is known as Coenzyme Q and it is a vital electron carrier in associated with complexes I, II, and III of the electron transport chain. In the body, it switches back and forth from its oxidized version Ubiquinone to its reduced version Ubiquinol
What is a substance's standard state?
Under standard conditions (25 C, 1 atm pressure, 1 M concentration) the state (gas, solid, or liquid) a substance takes is its standard state. FOr example, oxygen, at standard conditions, is a gaseous, neutral, diatomic compound. Iron, at standard conditions, is a solid, neutral, monoatomic compound.
What is a vacuum distillation?
Vacuum distillation is just like simple distillation, except a vacuum adapter is used and hooked up to a vacuum that lowers the atmospheric pressure inside the distillation apparatus. By lowing the atmospheric pressure, one lowers the boiling points of all liquids present in the distilling flask. This method is used on compounds with higher than 150 C boiling points to lower their boiling points. Heating a reaction mixture past 150 C is not a good idea, because it will put so much heat energy into the solution that it will probably cause it to start undergoing undesired reactions.
Scalar vs Vector Quantities
Vector Quantities depend on direction.
What is velocity?
Velocity is a vector quantity that describes the change in displacement per unit of time.
Should you place a voltmeter in parallel or series?
Voltage is equivalent across parallel elements and split between series elements. Therefore, one should wire a voltmeter in parallel with the two points between which one wants to measure the voltage. If you place the voltmeter in series with the two points, the voltage will be split and the voltmeter will read lower than the actual voltage.
What are the units of potential?
Volts (V = J/C)
How do we name carbons relative to the carbonyl group?
We could just call any specific carbon out on the chain using its number, but we can also call out carbons as they relate to the carbonyl group. Alpha carbons are carbons that are adjacent to the carbonyl carbon. Beta carbons are carbons that are two away from the carbonyl carbon. Gamma carbons are three away. Delta carbons are 4.
Why do we need to know about effective nuclear charge?
We need to know about effective nuclear charge because inner electrons shield the outer electrons from the charge of the nucleus. This means that, even though the electrons are all being pulled upon by the same nucleus, that pull varies for each electron.
How do we know which substituents have higher priorities than others in naming E/Z and R/S?
We use Cahn-Ingold-Prelog Priority rules.
When do we use fractional distillation?
We use fractional distillation when we are trying to distill a liquid that has a boiling point less than 25 degrees C different than another. For example, we would use fractional distillation to separate two liquids with boiling points of 100 and 115, but not on two liquids with boiling points of 100 and 145.
How do we signifiy groups that are bound to nitrogens in nitrogen containing compounds?
We use the prefix N- instead of a number to indicate that the group is bonded to a nitrogen.
How does one create a lewis structure for an atom/molecule?
We will use the example of HCN to illustrate the steps of lewis dot structure construction. 1. Draw out the backbone of the compound, that is, the arrangement of the atoms. In general, the least electronegative atom will be the central atom, and Hydrogen and Halogens almost always occupy a terminal position. For now, just make single bonds between them. 2. Add the valence electrons of each individual atom in order to determine how many valence electrons you have total to use. 3. Place the electrons in the lewis structure, trying to do the best job you can of making sure everyone is in an octet and everyone has a formal charge of 0. 4. Sometimes it will be impossible to get every atom to an octet with the number of valence electrons in the compound. In this case, try to replace single bonds with double bonds/triple bonds strategically. The use of double and triple bonds will almost always allow you to get every atom to an octet.
What is a phase change?
When a molecule goes from one phase (gas for example) to another (liquid for example).
Uniform Circular Motion
When an object is moving at a constant speed in a unfirom circular motion. The acceleration is always toward the center of rotation. The acceleration is only changing the direction of the velocity to keep it moving. If the object were detached and no external force is acted on it it will travel in a straight line at constant velocity
What is the zeroth law of thermodynamics?
When an object x is in thermal equilibrium with an object y, and that object y is in thermal equilibirum with another object z, x will be in thermal equilibrium with z.
What is uniform circular motion?
When an object's instantaneous velocity vector is tangent to the circular path but centripital force (which is pointed radially inward) keeps the motion circular. Do not count centripedal force as a force on objects.
What is gamma decay?
When an unstable nucleus emits a gamma ray AKA a high energy photon. Gamma rays are massless and chargeless, they just carry energy and their emission helps to stabilize a high energy nucleus. They do not affect the atomic number or mass number of a nucleus.
When do we use vacuum distillation?
When we are trying to distill a liquid with over a 150 C boiling point. The whole point of vacuum distillation is to decrease the pressure in the system, which lowers the boiling point of the liquid so we don't have to worry about degrading the product with that much heat.
When do we assign positive or negative values to work?
When work is being done on the system (compression) or work is being done by the system (expansion).
How do reactions respond to changes in concentration, as described by Le Chatelier's principle?
When you increase the concentration of something at equilibrium, the equilibrium will oppose this change by pushing the reaction to the other side of the equation. When you decrease the concentration of something at equilibrium, the equilibrium will oppose this change by running the reaction to the same side of the equation so it can replace what was lost.
What happens when you multiply numbers with exponents?
When you multiply numbers with exponents, the exponents add up.
What happens when you take the log of the product of two numbers?
When you take the log of the product of two numbers, the answer is equal to the sum of the log of each number individually.
How does one calculate the speed of sound in a given medium?
Where B is the bulk modulus of the material and rho is the density. v=(B/p)^(1/2)
Capacitors store energy by separating charges and creating an electric field in which to store energy. How does one calculate the amount of electrical potential energy in a capacitor?
Where C is the capacitance of the capacitor and V is the potential across the capacitor.
How does one calculate the modified capacitance due to a dielectric?
Where C is the original capacitance and k is the dielectric constant.
How does one calculate the amount of work done on an object?
Where F is the force, d is the distance over which the force was applied, and theta is the angle between the force and the displacement vector. W=dKE/PE W=F*d*coso
How does one calculate sound level?
Where I is the intensity of the sound wave and Io is the threshold of hearing 1*10-12
How does one calculate the wavelength of the standing wave in a closed pipe?
Where L is the length of the pipe and n is limited to odd integers above zero (1,3,5... etc.)
What is the equation for the wavelength of a standing wave on a string?
Where L is the length of the string and n is a non-zero positive integer known as the harmonic.
How do you calculate the change in volume and molarity during a dilution?
Where Mi is the initial Molarity, Vi is the initial volume, Mf is the final molarity, after dilution, and Vf is the final volume, after dilution.
What is the equation for calculating the absolute(hydrostatic) pressure on an object?
Where Po is the ambient pressure on the liquid (usually atmospheric pressure but not always) and pgz is the pressure due to being submerged in the liquid. z indicates the depth at which the object is submerged. Remember gauge pressure only deals with height difference. Does not matter the shape container. Anything on the same level has no effect. Calculates the pressure at certain heights.
How does one relate the equilibrium constant for a reaction and the standard gibbs free energy of the reaction?
Where R is the ideal gas constant 8.314, T is the temperature, and Keq is the equilibrium constant.
What is the equation for the Nernst Equation?
Where R is the ideal gas constant, T is temperature, n is the number of moles exchanging, F is the faraday constant, and Q is the reaction quotient. If the temperature is at 298 K (Standard conditions) the following simplified version of the equation can be used.
How does one calculate the energy required to promote an electron from one energy level to another?
Where RH is the Rydberg constant, ni is the initial energy level and nf is the final energy level.
What is the equation for the delta G of an electrochemical cell?
Where delta G prime is the standard gibbs free energy, n is the number of moles of electrons exchanging between the anode and the cathode, F is the Faraday constant, and Ecell is the standard electrode potential.
How does one calculate a fluid's critical speed?
Where v is the critical speed. Eta is the viscosity. p is the density. D is the diameter of the tube. NR is a constant known as Reynold's number which changes based on the size and shape of objects within the fluid.
Do nonionic solutes contribute to the conductance of an electrolytic solution?
Yes, but negligibly. The concentration of the ionic solutes in the solution will always be more important than the nonionic solutes for determing conductance.
Do diastereomers rotate plane polarized light?
Yes, but they rotate plane polarized light in weird ways. It's not like with enantiomers how its the same amount just in opposite different directions. For this reason, the optical activity of diastereomers is not as useful to analyze.
What is yield?
Yield refers to the amount of producted predicted or actually obtained when a reaction is carried out.
What should the change in total mechanical energy of an object be equal to when only dealing with conservative forces?
Zero
Describe sp2 orbitals.
sp2 - seen in molecules with 3 areas of electron density. Results from the combination of an s orbital and 2 p orbitals. There is one p orbital left unused. This p orbital can interact with other nearby p orbitals to form a pi bond.
Describe sp3 orbitals.
sp3 - seen in atoms with 4 areas of electron density. Results from the combination of an s and all 3 p orbitals. No free p orbitals to pi bond with.
What is the formula for calculating the force on a current carrying wire placed in a magnetic field?
where I is the current, L is the length of the wire, B is the strength of the magnetic field, and theta is the angle between the magnetic field and the length of the wire.
How does one relate standard gibbs free energy of a reaction and non standard gibbs free energy of a reaction?
where R is the ideal gas constant 8.314 and Q is the reaction quotient of the reaction (concentration of products raised to their coefficients divided by concentration of reactants raised to their coefficients).
How does one calculate the frequency of the vibration of a string?
where f is frequency, T is tension in the string, p is the linear density (mass per unit of length), and lambda is equal to the wavelength. f=(B/p)^(1/2)/wavelength
What is the equation for the distances of objects and images in optics?
where f is the focal length, o is the length at which the actual object is, and i is the length at which the image of the object is. NOTE: Different types of optics will have different sign conventions. It's extremely important you remember the sign conventions for the different optics and assign them correctly.
How does one calculate the energy of a photon?
where f is the frequency of the proton and h is planck's constant
How does one calculate the magnification of an object?
where i and o are the distances to the image and the object, respectively.
What is the equation to calculate the force on a charged particle moving into a magnetic field?
where q is the charge, v is the velocity of the particle, and theta is the angle between the magnetic field and the velocity vector of the particle
What is the equation for the heat absorbed or released due to change in temperature?
where q is the heat, m is the mass, T is the temperature, and c is the specific heat of the substance.
What is the formula for Coulomb's law?
where q1 is the charge on the first particle, q2 is the charge on the second particle, r is the distance between the particles, and k is the Coulomb constant = 9*109
What is snell's law of refraction?
where the n's are the indices of refraction for the two media and the theta's are the angle from the normal of the two media. It is important to make sure you know exactly which angle is which and how to identify them on test day. Picture below clearly labels the angles.