Phys 101 exam 2
Which wave has the largest amplitude?
(The one with the biggest bumps)
What is the charge of iron (Fe) in the compound Fe2O3?
+3
What would be the charge of bromine, Br, in order to satisfy the octet rule?
-1
How many electrons would potassium, K, need to get rid of to satisfy the octet rule?
1
A sample of radioactive material with a half-life of six hours sits for a day (24 hours). How much of the original radioactive material remains?
1/16th
A sample of radioactive gas is produced. After 20 minutes, only 1/4 of the original gas remains. What is the half-life of the gas?
10 minutes
The Second Law of Thermodynamics (Law of Increasing Disorder) places limits on the efficiency of energy conversion. Which of the following is allowed?
100% conversion of electricity to ambient temperature thermal energy
In the chemical equation C6H12O6 + 3O2 => 3CO2 + 6H2O, how many oxygen atoms are on the right side of the equation?
12
Each molecule of methane has the formula CH4. If there are 4,000 carbon atoms present, how many hydrogen atoms will be required to convert all the carbon atoms into methane?
16,000
How many hydrogen atoms are in three cis-platin molecules (3PtCl2N2H6)?
18
The mass of a chlorine atom in atomic mass unites is approximately 35. The atom has
18 neutrons
How many electrons will need to be shared between the two chlorine atoms?
2
How many electrons would sulfur need to gain to satisfy the octet rule?
2
How many more electrons does unbound oxygen need to fill its 2nd shell?
2
Now ask yourself how many potassium (metal) atoms are needed to give all the electrons that one sulfur (nonmetal) atom wants to take
2
What would be the charge of calcium, Ca, in order to satisfy the octet rule?
2
How many nonmetal atoms (bromine) are needed to take all the electrons that the metal atoms (calcium) want to give?
2 bromide atoms, 1 calcium atom
Carbon and oxygen react according to the equation: 6O2 + C6 -> 6CO2. If the reactants in the box react completely, which of the pictures below best represents the total products that are formed?
2 oxygen for every carbon, symmetrical (looks like 3 in a row)
Uranium-238 alpha decays, emitting a helium-4 nucleus. What is the mass number of the product?
234
Which of the following is a correct and balanced equation showing the reaction of calcium and oxygen?
2Ca + O2 = 2CaO
In which of the following processes is the end product more ordered than the reactants? (In which process does entropy decrease in the system?)
2H2 (gas) + O2 (gas) = 2 H2O (gas)
How many electrons does a nitrogen (N) atom "want"?
3
If the activity of a radioactive substance drops to 1/16 of its initial value in 12 hours, what is its half life?
3 hours
Light travels
3 x 10^8 meters/second
Each orbital can hold two electrons. How many bonding orbitals will there be in a N2 molecule?
3. A triple bond
How many bonds does each carbon have in propanol?
4
If two nitrogen atoms combine to make N2, how many total electrons need to be shared between the two atoms?
6
If two nitrogen combine to make an N2 molecule, how many total electrons will be shared?
6
Suppose the carbon and oxygen react according to the equation: O2 + 2C = 2CO. If you'd started with sixty oxygen molecules (60O2) and sixty carbon (60C), how many carbon monoxide molecules could you make?
60
To have a "full" shell, most atoms "want" to have how many total electrons in their outermost shell or subshell
8
Plasma force support
??? Too complicated ???
The diagrams show how a photon can be emitted from three different semiconductors: one red, one yellow, and one blue. Which emits a red photon?
A (the longest distance)
Ionic bond
A bond formed between positive and negative ions that is held together by the electromagnetic force
If you shoot particles at two slits, what will you see on the screen? (Shooting paint balls would be a good example of shooting particles at a screen)
A bunch of dots clustered into two bands directly behind the two slits
Ion
A charged atom or molecule. An ion is negatively charged if the atom gained an extra electron or electrons. An ion is positively charged if the atom lost an electron or electrons. The charge of the ion is indicated by a superscript number listed after the element symbol or molecular formula, such as H+ (a hydrogen ion with a positive 1 charge) or CO3^-2 (a carbonate ion with a negative 2 charge)
Catalyst
A chemical that speeds up a reaction without being destroyed or consumed by the reaction
Alloy
A combination of two or more metals into a single homogeneous substance
Two or more different elements that are chemically combined are always what kind of substance?
A compound
Ionic compound
A compound formed between a metal and nonmetal
Polar covalent bond
A covalent bond between atoms that differ in electronegativity. The shared electrons are pulled closer to the more electronegative atom, making it slightly negative and the other atom slightly positive.
Molecular ion (or polyatomic ion)
A covalently bonded molecular ion is formed when an unstable grouping of atoms adds or loses extra electrons, forming stable but charged compounds. They can form an ionic bond w/ another oppositely charged molecular or metal ion
Potential energy surface
A diagram plotting the total energy of the reactants and products as chemical reaction occurs
Trans-fatty acids
A fatty acid with at least one double bond between the carbon atoms in the carbon chain. Where the double bond occurs, the hydrogen atoms have switched places to be on opposite sides of each other. This removes the kink in the molecule due to the double bond
Unsaturated fatty acids
A fatty acid with fewer than the maximum possible number of H atoms, which means there is at least one double bond between the carbons in the carbon chain
Saturated fatty acids
A fatty acid with the maximum possible number of H atoms, which means there are no double bonds between the carbons in the carbon chain
Covalent bond
A force that holds atoms together to make a molecule in the first place, not a force between molecules
Dipole-dipole interaction
A force that holds molecules together when that molecule has positive and negative ends
Dispersion force
A force that holds molecules together when the molecule is nonpolar
Molecular ion
A group of atoms covalently bound to each other that have a net charge because electrons have been lost or gained in order to form a stable covalent molecule
Triglyceride
A large molecule created by reacting three fatty acids with glycerol
What is a material that will flow to assume the shape of its container, but will maintain its volume?
A liquid
Moderator
A material used to slow down neutrons, which increases the likelihood of the neutron being absorbed by the large nucleus
Solvent
A material, usually a liquid, in which another material dissolves
Electronegativity
A measure of how strongly atoms attract electrons. Electronegativity increases from the left to right across the rows of the periodic table and decreases down a column of the periodic table
Electronegativity
A measure of the ability of an atom in a chemical compound to attract electrons
Electrical conductivity
A measure of the degree to which a substance conducts electricity. It is how easily current can move through a substance
Thermal conductivity
A measure of the degree to which a substance conducts heat. It is how easily heat can move through a substance
The substance that a wave travels through is known as what?
A medium
Solution
A mixture containing at least two compounds with at least one o the compounds in liquid form
Polar molecule
A molecule that has an unequal distribution of charge so that one end is positive and the other end is negative. Water is an example of a polar molecule
Fatty acids
A molecule with a long hydrocarbon tail and an acid group - COOH at the other end
A metal can best be described as
A network solid consisting of positively charged atoms in a sea of electron
Which of these statements best describes a metal?
A network solid consisting of positively-charged atoms in a sea of electrons
Transition state
A new complex formed by the addition of energy to excite molecules
Which of the following would best describe the characteristics of the material formed?
A non-conducting material with low melting and boiling points, likely liquid or gas at room temperature
What is a material that doesn't conduct electricity regardless of whether it is in a liquid state or solid state called?
A nonconductor
Nucleon
A particle found in the nucleus - proton or neutron
What is the best description of a photon?
A particle without mass and no charge
Which of these processes is closest to an ideal reversible process?
A pendulum swinging with almost no friction
Positron
A positive electron
Irreversible process
A process in which the total amount of disorder in the universe increases
Reversible process
A process in which the total amount of disorder in the universe remains the same
Entropy
A quantitative measure of disorder. It increases as disorder increases
Law of increasing disorder
A reversible process does not change the total amount of disorder in the universe. An irreversible process increases the total amount of disorder in the universe
N-type semiconductor
A semiconductor with extra electrons in the valence band. It is formed by adding a different semiconductor that has more valence electrons than the host semiconductor to the host semiconductor. Phosphorus can be used to create an N-type semiconductor
P-type semiconductor
A semiconductor with vacancies in the conduction band. It is formed by adding a different semiconductor that has fewer valence electrons than the host semiconductor to the host semiconductor. Aluminum can be used to create a P-type semiconductor
Light from a laser shines on a pair of closely spaced slits and then fall on a screen. No attempt is made to detect the light until it hits the screen. What best represents the resulting image on the screen?
A series of bright and dark bands
Glycerol
A small molecule that contains only three carbons and reacts easily with molecules that belong to the family of organic acids
System
A small piece of the world around which we draw a mental box and upon which we focus our attention
Oil
A substance that is liquid at room temperature and that does not dissolve in water but can dissolve in hydrocarbon liquids
Fat
A substance that is solid at room temperature and that does not dissolve in water but can dissolve in hydrocarbon liquids
Atomic mass unit (amu)
A unit to measure mass of very small amounts. 1 amu = 1.66 x 10^-27
A proton has a mass that is ___ than the mass of a neutron
About the same
Black light
Absence of any colors of light
The energy required for a reaction to take place is known as the
Activation energy
Chemical reaction rate
Affected by conditions such as temperature, pressure, and even concentration of molecules
If GaAs forms a semiconductor like Ge, which of the following elements will form a semiconductor like Si?
Al and P
Reflection
All mechanical waves travel through a medium. When a wave encounters a change in medium, part or all of the wave bounces off the boundary between the two different substances. When a wave bounces off the surface of a new medium, it is reflected
What combinations of atoms make covalent bonds?
All of the atoms are nonmetal
What are compounds between two different metals called?
Alloys
Which of the following is not why alloys are useful to us today?
Alloys have a higher conductivity rate.
Which of the following describes a wave property, not a wave phenomenon? Select all that apply.
Amplitude, frequency
Octet rule
An atom will most likely form an ion that has the ns^2np^6 configuration of the closed noble gas
Isotope
An atom with the same number of protons but a different number of neutrons
Beta particle
An electron
Which of the following processes is closest to an ideal reversible process?
An ice cube floating in a glass of water at zero degrees
Lithium fluoride does not conduct electricity as a solid, but will conduct if melted or dissolved in water. What kind of material is it?
An ionic material
Molecular orbital
An orbital (standing waves describing the probability of finding an electron) around the two or more nuclei that compose the molecule in question
Atomic orbital
An orbital (standing waves describing the probability of finding an electron) that is associated with a single atomic nucleus
Salt
Another name for an ionic compound
Molecules in matter
Are constantly moving about, sometimes colliding with one another. During collisions, molecules exert forces on one another, exchange energy, and change direction
Different kinds of matter
Are made up of different molecules
Opacity and Luster
Are opaque, cannot see through them. They are shiny, high reflectivity, called a metallic luster
What is the relationship between mass and the average speed of the molecules?
As mass increases, the average speed decreases
What is the relationship between temperature and the average speed of the molecules?
As temperature increases, the average speed increases
Salt
At least one metal and nonmetal bonded together to form network matter
Amu
Atomic mass unit; a measure of mass used for atoms
Number of protons
Atomic number
Number of electrons
Atomic number but only in a neutral atom
Network matter
Atoms are connected together
Bond
Attractive interaction between atoms
As the temperature of the water increases from 30*C to 80*C, which of the following is also increasing?
Average kinetic energy of the molecules
When you compare the melting point of the 3 molecules, what do you find? (Butylene molecule can actually form 3 different ways)
B does, the curved ones. Kinks = lower melting point
As a compression elastic wave passes through a medium, how does each piece of the medium move?
Back and forth in a direction parallel to the direction the wave is traveling
Why is cookware (pots and pans) most often made of metal?
Because it is easy to shape into a pan, has a high melting point, and is a good conductor of heat and electricity
In another experiment that provides information about the nature of light, we can shine light on a pair of slits. When very dim light is shone at a pair of closely spaced slits, the pattern shown below develops. Initially, the dots of light appear random, but as they accumulate, a pattern emerges. When you look at the image to the right, why does light passing through two slits produce 5 lines?
Because light is a wave and waves interfere
Why are metals opaque?
Because metals have empty, overlapping orbitals for their electrons that create very closely spaced energy levels
When you hit oobleck (corn starch + water (slime)) with a hammer, why does it act like a solid?
Because the hammer exerts a shear force and only solids can resist shear forces
Why is overheating such a problem for electronics?
Because the hotter a semi-conductor becomes, the better it conducts electricity
What best explains why metals are opaque and shiny?
Because there are so many empty orbitals that the electrons can absorb and emit any frequency of light
A box has a separator between molecules. When does the system have more order
Before the separator is removed
In which kind of radioactive decay would the number of protons in the resulting nucleus be more than in the initial nucleus?
Beta decay
Polar
Bonds or molecules having an unequal distribution of charge so that one end is positive and the other end is negative
I change direction when I change what material I am traveling through. What am I?
Both waves and particles do this
Which of the following is not a characteristic of a metal or alloy?
Brittle
Which of these statements best describes the room temperature characteristics of ionic substances?
Brittle, non-conducting solid with high melting points
Which of the following would best describe the room temperature characteristics of the substance that results from the reaction between magnesium (Mg) and oxygen (O)?
Brittle, transparent, electrically non-conducting solid.
Which of the following would best describe the room-temperature characteristics of an ionic substance?
Brittle, transparent, electrically non-conducting solid.
Which of these equations is balanced correctly?
C + O2 = CO2
What is the formula for Ethene?
C2H4
What is the chemical formula for acetaldehyde?
C2H4O
Which of the equations below is balanced correctly?
CH4 +2O2 ⇒ CO2 + 2H2O
Which ion would Ca most likely form?
Ca2+
What would be the chemical formula of the ionic compound between calcium and bromine?
CaBr2
What would be the name of this ionic compound?
Calcium bromide
Malleability
Can be hammered without shattering
Polar molecule
Can result if the dipoles of the individual parts of the molecule add up to create a total dipole for the entire molecule
Satisfy octet rule- Lattice
Carbon atom form single bond w/ 4 neighboring carbon atoms- forms lattice structure that we call a diamond (extremely high melt temp- if you try to melt diamond you are breaking covalent bonds b/t atoms rather than intermolecular forces b/t molecules)
According to Dr. Planck's model, if I want to knock electrons off of a negatively charged electroscope, how would I increase the energy of the light particles?
Change the color to purple, or better yet UV or x-rays
Bonding orbital
Chemical bond can occur with this type of orbital
Pure substances
Chemical matter that have defined and unchanging chemical compositions
What happens to the entropy of the universe as the products are formed in an exothermic chemical reaction?
Chemical potential energy is converted into thermal energy resulting in an increase in entropy
What happens to the entropy of the universe as the products are formed?
Chemical potential energy is converted into thermal energy resulting in an increase in entropy.
Which of these elements from diatomic gases?
Chlorine (C), Nitrogen (N), Hydrogen (H), Oxygen (O)
Which of the following is not used as a measurement technique for identifying chemical substances?
Color spectroscopy
White light
Combination of all colors of light
Salts have which of these properties?
Combination of metal and nonmetal atoms, ionic bonds, transparent
Fusion
Combining of two smaller nuclei to make a larger nucleus. Energy is released
Tension Forces
Come from pulling on or stretching the object
Compression Forces
Come from pushing on the object
Shear Forces
Come from sliding it in opposite directions on each side or twisting the object
A sound wave is an example of what type of wave?
Compression
Gas force support
Compression
If you pluck a guitar string, what type of wave does the soundboard produce in the air?
Compression
Liquid force support
Compression, tension
Solid force support
Compression, tension, shear
When a material conducts electricity in the solid and liquid forms, what is it called?
Conductor
Fuel rods
Contain isotopes that undergo fission
Mixtures
Containing multiple substances
A rainbow is an example of a ___ spectrum
Continuous
Which of the following substances is most likely to be a pure element?
Copper
Bonds are localized (I.e. molecules, not network solids, are formed)
Covalent
What type of bond would exist between the carbon and oxygen?
Covalent
The bond between two nonmetal atoms
Covalent bond
Quadruple bond
Covalent bond involving four pairs of electrons (8 electrons) shared between two atoms. This type of bond rarely occurs and is most stable among the transition metals
Single bond
Covalent bond involving one pair of electrons (2 electrons) shared between two atoms. It is represented by a single line (-)
Triple bond
Covalent bond involving three pairs of electrons (6 electrons) shared between two atoms. It is represented by a triple line
Double bond
Covalent bond involving two pairs of electrons (four electrons) shared between two atoms. It is represented by a double line (=)
Energy levels are widely spaced
Covalent, ionic
Bonds arise from electrostatic interactions
Covalent, ionic, metallic
Does a double bond between two carbon atoms increase or decrease the number of hydrogen atoms that could bond to carbon in these molecules?
Decrease
If the average kinetic energy of the water molecules decreases, their temperature will
Decrease
If the fastest ones leave, the average kinetic energy of all the water molecules left behind will
Decrease
Would adding another double bond between two carbon atoms increase or decrease the number of hydrogen atoms that are bound to carbon in these molecules?
Decrease
Chemical equation
Describes chemical reactions
Number of neutrons
Difference of mass number minus atomic number
When sunlight passes through a large opening, such as a door or window, it is concentrated immediately behind the opening. When light passes through a very small opening, such as a pin hole, it spreads out over an area much larger than the size of the opening. This is an example of what?
Diffraction
Waves may be observed to reflect, refract, diffract, and interfere. Two of these behaviors are unique to waves only and two of them may also be observed for particles (or convincingly counterfeited by particles). Which two are wave behavior only?
Diffraction and interference
Ultraviolet light ("black" light)
Dim Light: Electrons knocked off slowly; Bright Light: Electrons knocked off quickly
Visible light
Dim Light: No electrons knocked off; Bright Light: No electrons knocked off
Nonpolar
Dipoles are symmetrical, even and opposite, so they cancel out
Polar
Dipoles are uneven on the molecule
Entropy is a measure of the ___ of a system
Disorder
Which appears more chaotic, the gas with the higher temperature or the lower temperature?
Disorder is greater when the temperature is higher
For the Butylene molecule C, what forces would be the largest forces holding one of the molecules to another molecule? (What are the largest intermolecular forces?)
Dispersion forces
Rank the following according to their strength, weakest first, strongest last
Dispersion forces, dipole-dipole interactions, hydrogen bonding, covalent bonding
Quadruple bond
Doesn't really happen- fitting the waves for 8 electrons b/t two atoms creates too much electromagnetic repulsion
Chemical potential energy is one form of internal energy. What is the source of chemical potential energy?
Electrical potential energy of molecules
Intermolecular forces
Electromagnetic forces between individual molecules. These forces are weak when compared to the forces between the individual atoms making up the molecule itself
Metallic bonds
Electrons move freely
Molecular matter
Elements have strong interactions between a set number of the same element so molecules are formed, but there are weak interactions outside the individual molecules
Daughter
Elements produced in a radioactive decay process. The daughter elements are found on the right side of a nuclear reaction equation
Parent
Elements that decay into a different element in a nuclear reaction. The parent elements are found on the left side of a nuclear reaction equation
In a mechanical wave, what is actually traveling from one place to another?
Energy
What happens to the energy of the system as this compound is formed?
Energy decreases
In order for an energetically favorable chemical reaction to occur
Energy must decrease as a result of the reaction
Activation energy
Energy that has to be added to start the reaction
A car can't convert all the energy from its fuel to macroscopic kinetic energy. Why?
Entropy would decrease
When two molecules collide, the force each exerts on the other is ___
Equal
Surroundings
Everything outside the system
Surroundings
Everything outside what we have defined to be the system
N-type semiconductor
Extra electrons
Which of the following is an example of refraction?
Eyeglasses correcting a person's vision
A very fast reaction has a very high activation energy
False
Because it is possible to separate the atoms back into different areas, the process is reversible
False
Dispersion forces are stronger than covalent bonds
False
Dispersion forces, polar forces, and hydrogen bonding are all types of bonds that hold atoms together to make molecules and compounds
False
Fatty substances that are solid at room temperature are classified as oils
False
If a molecular material is solid at room temperature, the high melting and boiling temperatures indicate there must be polar forces holding the molecules together
False
In the future, engineers will be able to design a car that is 100% efficient
False
It is impossible to do work and sort the molecules into separate areas
False
It is possible to predict exactly when a radioactive nucleus will decay
False
Metals have higher ionization energies than nonmetals do
False
Mica is a silicate that has strong bonds throughout its entire structure
False
Molecular orbitals are the same shape as atomic orbitals
False
Quartz, a mineral with no regular pattern when seen in large quantities, has fibrous layering in its atomic structure
False
The energies of the orbitals that form when metals interact are very widely spaced in energy
False
The forces between N2 molecules are very strong
False
The molecular model cannot explain why the pressure of a gas in a container with fixed volume,s inch as car or bike tires, increases with increasing temperature
False
The temperature at which a liquid evaporates to form a base is different from the temperature at which the gas condenses to form a liquid
False
True or false: Current can flow in all directions in an LED
False
True or false: Molecular ions are poor conductors of electricity in solid and liquid forms
False
True of false: A valence electron in a nonmetal has a very low ionization energy
False. As you go from left to right across a period, the ionization energy increases. Nonmetals are on the right side of the periodic table, so they have high ionization energies
Are the fastest or slowest molecules more likely to have the energy to "escape" (evaporate) from your finger
Fastest
Monounsaturated fats
Fats containing fatty acids with a single double bond
Polyunsaturated fats
Fats containing fatty acids with two or more double bonds
Which of the following fatty acids is best for human health?
Fatty acids that have one or more 'bent' cis-double bonds between carbon atoms
It has been harnessed for commercial electricity generation
Fission
It involves breaking up large nuclei into smaller ones
Fission
In acetaldehyde, how many of each type of bond are there?
Five single, one double, zero triple
Liquid
Fixed volume, change shape to match container
Gases are
Fluids
Pressure
Forces exerted on walls by collisions between molecules
Ionic bonds
Form because the energy of the resulting product is lower in energy and the entropy of the universe increases
Thermal energy
Form of energy that flows or conducts between two objects because they are at different temperatures
What is the energy of a photon related to?
Frequency
Wave speed =
Frequency x wavelength
Complete conversion of one form of energy to another can occur only in which direction?
From higher to lower organized forms
Advantages for fusion energy production
Fuel inexpensive and readily available, doesn't release greenhouse gases, fuel and byproducts aren't useful in making weapons, no risk of catastrophic nuclear accident, and radioactive byproducts are relatively easy to contain and dispose of
Fission reactor problems
Fuel is relatively expensive and rare, byproducts of the reactor have dangerous radioactivity, danger of fuel being misappropriated for weapons, though very rare, mistakes, accidents, or natural disasters at the reactors can result in serious accidents create dire environmental and health hazards
Fuel for the process is relatively plentiful on earth
Fusion
It combines small nuclei to make larger ones
Fusion
It occurs on the sun
Fusion
Primary process in the most powerful nuclear weapons
Fusion
Band gap
Gap between the highest energy occupied states and the empty conduction band, gives a semiconductor different properties than a metal
Which of the following set of properties is most likely those associated with methane, a covalently bonded compound?
Gas at room temperature, colorless, does not conduct electricity when solid
Which of these sets of properties is most likely those associated with methane, a covalently bonded compound?
Gas at room temperature, colorless, does not conduct electricity when solid
What best depicts how the temperature of the water varies with time as it changes from ice to liquid to steam?
Going up like stairs
Metals have which of these properties?
Good electrical conductors, malleable, shiny, metals easily form alloys
The motion of molecules
Governed by the laws of motion, force, and conservation
Satisfy octet rule- Sheets
Graphite is 2nd structure formed- carbon atoms arrange in sheets. There are covalent bonds b/t atoms in the same sheet but interaction b/t atoms in diff sheets is v diff. Some electrons are in orbitals that are delocalized on the surface. These electrons form a very weak version of a covalent bond b/t sheets- allows sheets to "slide" past one another and makes graphite useful as a lubricant
What type of energy is the most ordered?
Gravitational potential energy
Order the following substances from lowest to highest density: granite rock, helium gas, and ocean water
Helium gas, ocean water, granite rock
Alpha particle
Helium-4 nucleus
How would you describe the melting point of a substance formed by a molecular ion?
High
Why is a high temperature required for nuclear fusion to occur?
High temperatures are required to allow the nuclei to have enough kinetic energy to overcome the electromagnetic repulsion and have the strong force attraction take place
Gamma ray
High-energy, high-frequency electromagnetic radiation
Described experiment
Higher frequency light discharged the electroscope
Wave Speed
How fast it is moving (disturbance is moving, not the medium- only changes when a wave passes from one medium into another or when some characteristic of the medium changes)
Wavelength
How long the wave is. Measured from crest to crest or trough to trough, or point on wave to whenever the wave repeats itself at the same point
Frequency
How many waves occur in a second (count how many crests/troughs pass in a second) ((related to wavelength))
Which of the following is a true statement about melting and boiling points in materials made of covalent molecules?
Hydrogen bonding between molecules increases melting and boiling points
Rule of reaction
If the new molecular orbital is lower in an energy well and overall entropy increases, electrons go to this state and can't get out- thus, a chemical bond is formed. This chemical bond is stable unless energy is added
In a bonding orbital between two atoms, where is the electron density the highest? (Where do you have the highest probability of detecting an electron?)
In between the two atoms
In the early 1800s scientists demonstrated that light was a wave. How do you increase the energy of a wave?
Increasing the amplitude
Dr. Maxwell Planck developed a particle model of light. In his particle model, how do you increase the energy of the photons?
Increasing the frequency
Control rods
Inserted into the reactor to control the rate of reaction
Hydrogen bonds
Interactions between hydrogen atoms bound to oxygen, nitrogen, or fluorine atoms bound with oxygen, nitrogen, or other fluorine atoms. Hydrogen bonds are among the strongest of the intermolecular interactions
Chemical bonds
Interactions between the atoms in a single molecule or network matter
Laser light passed through narrowly spaced slits to form a pattern of light and dark spots on a screen
Interference
The bond between a metal and a nonmetal
Ionic bond
Which of the following is unimportant in the determining in the characteristics of fatty acids?
Ionic bonds
Bonds are long-range
Ionic, metallic
An ice cube melts in a glass of warm water. This is an example of which type of process?
Irreversible
Pure aluminum metal has a melting temp of 660*C. The process of liquid aluminum freezing to solid aluminum at this temp is ___
Irreversible
Electromagnetic radiation
Is all radiation associated with accelerating electric charges
Electromagnetic radiation when divided into its smallest state and unobserved
Is described by waves- shown in experiments like showing effects of diffraction and interference
Electromagnetic radiation when divided into its smallest state and observed
Is particles- shown in experiments like the photoelectric effect and looking at dim images on a CCD (detector) in a camera
What is the term for two atoms that have the same atomic numbers but different atomic mass numbers?
Isotopes
As you change the frequency what happens to the wave?
It changes width left-to-right
As you increase the amplitude what happens to the wave?
It gets taller up-and-down
As the temperature of a material increases, what happens to the average kinetic energy of the molecules of the material?
It increases
In an irreversible process, what happens to the overall disorder of the universe?
It increases
Objects normally contract when you cool them. As an object contracts, what happens to its density?
It increases
What happens to the wave speed as the tension in the string increases?
It increases
We see a large amount of order in the world around us, from life to currents in the air and ocean. How is this consistent with the law of increasing disorder?
It is because the sun provides additional high-order energy to the world to create this order
Which of the following correctly applies the law of increasing disorder to an air conditioner?
It is true that the heat flow from the cold region to the hotter region increases order, but this is made up for by increasing the disorder of energy from another source
How does a catalyst affect a reaction?
It lowers the activation energy
What would be the chemical formula of the ionic compound between potassium and sulfur?
K2S
Which if these is the most ordered form of energy?
Kinetic energy
On average, molecules in the gaseous state are farther apart than those in the solid state. For this reason, the internal electrical potential energy of molecules in the solid is ___ that of molecules in the gaseous state
Less than
When a heavy molecule collides with a lighter molecule, the acceleration of the heavy molecule is ___ that of the lighter molecule
Less than
Continuous spectrum
Light from the sun or a common lightbulb
What does this demonstrate about the behavior of light?
Light has wave properties
When sunlight passes through a large opening, such as a door or window, it makes a bright spot about the size of the opening. When light passes through a very small opening, such as a pin hole, it spreads out over an area much larger Thant he size of the opening. Why does this occur?
Light has wave properties
What does this mean about light?
Light is acting like a particle, not a wave
Discrete spectrum
Light made by passing a current through a low-pressure gassed tube, and then passing it through a prism- spectrum consisting of distinct bars of particular colors
These graphs show energy as a function of time for several different reactions. Which of the reactions shown below would end up absorbing energy from the surroundings?
Line rises a bit and doesn't return below where the energy line is
Solutions
Liquid mixtures of compounds - one or more compounds are dissolved in another type of compound, such as water
Satisfy octet rule- buckminsterfullerenes (buckyballs)
Looks like a tiny carbon soccer ball. Have a free electron and can therefore conduct electricity- currently used in nanotechnolo
Properties of covalent materials
Low melting point (liquid or gas near room temperature), , insulator, brittle,
Antibonding orbital
Low probability of electrons being between the two atoms
What are some fluids?
Maple syrup, hydrogen gas, liquid nitrogen
Density
Mass divided by its volume (mass per unit volume) - depends on the type of material, not how much is present
Ionic conductors
Materials that are nonconductors (insulators) as solids, but conduct electricity as liquids or when dissolved in water (salt)
Solid
Matter has definite shape and volume
Mixture
Matter that contains multiple substances. These substances can be physically separated into their pure substances
Element
Matter that contains only one kind of atom
Compound
Matter that contains two or more kinds of atoms in a fixed and definite proportion
Pure substance
Matter that has a defined, unchanging chemical composition
Plasma
Matter that is so hot that charged particles making up the material no longer stick together but move independently of each other
At room temperature, liquid water has a density of about 1 g/cm^3, while that of liquid mercury is about 13.6 g/cm^3. What could possibly explain this?
Mercury's molecules have more mass and are larger
Which type of atom has valence electron states high enough in energy that they overlap with the stacked-together molecular orbitals that form the conduction band?
Metal
Which type of atom has valence electrons higher in the energy well?
Metal
Charge carriers (electrons or ions) are free to move in the solid state
Metallic
The bond between two metal atoms
Metallic bond
Thermal and electrical conductivity
Metals are good conductors of heat and electricity
Which of the following is a correct comparison of metals and semi-conductors?
Metals' resistance increases when temperature increases while a semi-conductors resistance decreases.
Magnesium chloride forms a solid in which two chloride ions are found for every magnesium ion, but no discrete molecules are observed in the solid. What is the simplest formula for this compound?
MgCl2
Which of the following is an ionic compound?
MgF2
Bonding molecular orbital
Molecular orbitals that have a high probability of finding electrons between the atoms' nuclei. A bond is likely to form with this orbital
Antibonding molecular orbital
Molecular orbitals that have a low probability of finding electrons between the atoms' nuclei. A bond is unlikely to form with this orbital
In the molecular model of matter, matter is said to consist of tiny units called
Molecules
How many double bonds exist between carbon atoms in these unsaturated fatty acids?
More than one
Covalently bonded substances
Most are colorless and transparent. Often are very toxic (there are exceptions to both, though)
How does the mass of a proton compare to the mass of an electron?
Much larger than the electron
Gas
Neither definite shape or volume- will expand to match both volume and shape of container
What would happen if the electroscope had a positive charge placed upon it (rather than a negative charge) and then visible light and ultraviolet light were shone on the electroscope? (Hint: Think about what happens with electrons in a positively charged object and how that would affect this environment.)
Neither the visible light nor the ultraviolet light would discharge the electroscope
What classification of matter is magnesium chloride?
Network matter
Which of the following tends to have the highest melting and boiling points?
Network matter
Molecular orbitals
New orbitals
Dipole-dipole interactions
Next strongest in intermolecular forces lineup after hydrogen bonds, slightly higher melt/boil temp, polar molecules and ionic materials dissolve better in a polar solvent
Which of the following are most chemically similar to Pd?
Ni and Pt
Are any colors absorbed when light hits a white sheet of paper?
No
Are the hydrogen atoms still balanced? H2 + O2 -> 2H2O
No
Consider a refrigerator and its contents to be the system. Warm food is cooled to a lower temperature. Warm water is cooled int ice freezer and eventually frozen to ice. Do these two processes, cooling food and freezing water, increase the entropy inside the refrigerator?
No
Do all the water molecules on your finger have exactly the same kinetic energy?
No
If you were to put your hand behind the back of an operation refrigerator, would you feel cold air coming out of the exhaust?
No
The unbalanced equation is as shown: H2 + O2 -> H2O. Are the oxygen atoms balanced?
No
The unbalanced equation is as shown: H2 + O2 -> H2O. Could you balance the oxygen atoms by changing H2O to H2O2?
No
Can sulfur be considered a compound? Why?
No, it is composed of only one type of atom
Atomic matter
Noble gases exist as individual atoms with little or no interaction between the individual atoms themselves
What colors are reflected when white light hits the black interior of a car?
None
Which type of atom has the highest ionization energy?
Nonmetal
The process that produces most of the explosive energy of a hydrogen bomb and that is believed to be responsible for the energy released by the sun is called
Nuclear fusion
Covalent bonds
Occur between two or more nonmetal atoms (BETWEEN)
Atomic orbitals
Occur within a single atom
Suppose Gas 1 is composed of N2 (mass 28) and Gas 2 is composed of O2 (mass 32). Both gases are at the same temperature. Which statement is true concerning the speed of the molecules?
On average, Gas1 molecules are moving faster than Gas 2 molecules
Reversible processes
Only occur in a very narrow set of idealized conditions- common in chemistry, but true reversible processes are not really possible
If I'm sent straight towards a pair of openings that are a bit larger than I am, spaced a bit farther apart than my size, I can only be found directly behind one or the other of the openings.
Only particles do this. You're a particle
If I'm sent straight towards an opening that is a little bigger than I am, I can be found both directly behind the opening, and for a good distance to either side.
Only waves do this. You're a wave.
The various forms of energy can be ranked according to their level of what?
Organization
The photoelectric effect shows that light has ___ properties
Particle
What will I see in the double-slit experiment if I put some sort of detector at one of the slits that will permit me to see which slit each photon goes through?
Particle pattern
Which of the following is the best general description of the behavior of the liquid water molecules?
Particles in random motion that collide, transfer energy, and exert forces according to the conservation laws and Newton's laws of motion.
What is true regarding red and blue light?
Photons from blue light have more energy
Spectrum
Picture of white light's constituent colors
The ___ of a gas is attributed to collisions of the gas molecules
Pressure
The modern definition of an element is a substance made up of atoms that all have the same number of what particle?
Protons
Elements
Pure substances composed of one kind of atom only
Compounds
Pure substances composed of two or more different kinds of atoms
Atomic matter
Pure substances, such as noble gases (group 8A), that exist as individual atoms with little or no interaction between the individual atoms themselves
Of the following, which has the longest wavelength?
Radio waves
An unstable nucleus which has a tendency to spontaneously change its form with the emission of high-energy particles or photons is said to be
Radioactive
Gamma decay
Radioactive decay process in which a gamma ray is emitted
Alpha decay
Radioactive decay process in which an alpha particle is emitted
Beta decay
Radioactive decay process involving a neutrino and an electron or positron
Which color is reflected when white light hits a red apple?
Red
Which has the longer wavelength? (Red vs Blue)
Red
Man looking at self in mirror
Reflection
Suppose you are in a room with no windows and no lights on but the door is open. Light from the hall fills most of the room. the light entering the room can best be explained by:
Reflection
A blue car ___ more blue light than any other color(s)
Reflects
Light focusing through a lens
Refraction
Water waves bending as they come to shore
Refraction
Amplitude of sound waves
Related to how loud sound is- loud sound = higher amp
Fuel rods
Rods of fissile material, usually uranium-235, but plutonium also can be used
Control rods
Rods used in a nuclear reaction to absorb neutrons and slow or stop the fission reactions
Which of the following pairs would you expect to be covalently bonded? (Covalent- closest on periodic table, ionic- farthest)
S and Br (diagonal, big electron difference)
What is the chemical formula for sulfur?
S8
When you compare saturated with unsaturated fatty acids containing the same number of carbon atoms, what is true?
Saturated fatty acids have more hydrogen atoms
Second law of thermodynamics
See law of increasing disorder
Polyatomic ion
See molecular ion
Dipole
Separation of positive and negative charges due to the polar bond- stronger if charges are separated more
What are the electrons in a covalent bond doing?
Shared between specific pairs of atoms
If you pluck a guitar string, what type of wave are you producing in the string?
Shear
Doppler effect
Shift in the frequency of a wave- caused as source of wave moves towards or away from you (closer = higher, further = lower) amount of shift in frequency depends on speed of source
Locate the elements palladium (Pd, atomic #46) and nickel (Ni, atomic #28) on the periodic table. If Pd is combined with Ni, which of the following characteristics will the product show at room temperature?
Shiny, malleable solid
Chemical equation
Shorthand notation for describing a chemical reaction
Amplitude of light (an electromagnetic wave)
Shown by brightness- bright light = higher amp
Potential energy surface
Shows how the energy of the system changes as the chemical reaction occurs
If the two chlorine atoms combine to make Cl2, what type of covalent bond will exist between the atoms?
Single
Moderator
Slows down he fast neutrons so that they are likely to interact with other nuclei in the fuel
Fusion
Smaller nuclei combine to form a larger nucleus
In which state of matter does nitrogen keep its shape and volume
Solid
Crystalline
Solid matter where the constituent particles are arranged in an orderly, repetitive pattern
Blend/composite
Solid mixture of compounds
Which is the best definition of an alloy?
Solid mixture of metals
Blends or composites
Solid mixtures of compounds
Alloy
Solid mixtures of different metals
Changes of state occur with increasing temperature in which following order?
Solid, liquid, gas, plasma
the gasoline engine of an automobile is considerably less than 100% efficient. This means that not all of the energy int he gasoline is turned into kinetic energy of the car. Which of the following best explains why?
Some of the chemical potential energy in the gasoline engine must become ambient thermal energy if the rest is to supply the kinetic energy of the automobile. This means some energy must be wasted
The gasoline engine of an automobile is considerably less than 100% efficient. This means that not all of the energy in the gasoline is turned into kinetic energy of the car. Which of these statements best explains why?
Some of the chemical potential energy in the gasoline must become ambient thermal energy if the rest is to supply the kinetic energy of the automobile. This means some energy must be wasted
Activation entropy
Sometimes reactions will only take place when the reactants are lined up in a particular orientation
Standing waves
Special type of interference- waves confined to certain boundaries produce interference patterns with waves traveling in opposite directions in the medium (if waves moving to left and right in medium have same amp, they can produce standing waves)
Catalyst
Speed up the rate of the chemical reaction, is a chemical
Fission
Splitting apart of a very large nucleus to make two smaller nuclei. Two or more neutrons are released, along with energy
Octet rule
States that atoms lose, gain or share electrons in order to acquire a full set of eight valence electrons
Network matter
Substances where every atom interacts strongly with many of its neighbors. An extended network of linked atoms or ions forms
Molecular matter
Substances where the elements have strong interactions between a set number of elements so molecules are formed, but there are weak interactions outside the individual molecules
Sugar is a covalent molecule that is solid at room temperature and dissolves easily in water. What does this information tell us about the molecule?
Sugar molecules are polar
Here are the common names and contents for a number of common substances. Four are compounds, one is not. Which is not a compound?
Sulfur, consisting of molecules having eight S atoms
If you pluck a guitar string, what type of wave are you producing in the soundboard?
Surface
Which of the following substances would you expect to have the highest melting point?
Table salt, which boils at 1413*C
Ionic bonds
Take electrons
As the hot stove delivers additional energy tot he container of water, the temperature of the water remains constant. Why does this happen?
The additional energy is becoming internal electrical potential energy int he water and vapor rather than changing the temperature
If you change how loud a sound wave is, what are you changing?
The amplitude
When the average speed of the molecules increases, what happens to the average force with which the molecules hit the walls of the container?
The average force increases
Which molecule has the highest average kinetic energy?
The average kinetic energies are the same (if they are at the same room temp)
If you increase gas temp but keep volume and # of molecules the same, what happens to the average speed of the molecules?
The average speed increases
When the water begins to boil, he adds some salt. Water molecules have less mass than the sodium atoms in the salt. At any given temperature, how does the behavior of the two compare?
The average speed of the water molecules is higher, but the average kinetic energy is the same.
Compare the density of a ball bearing and a cannonball made of the same material
The ball bearing and cannonball have the same density
If a white light is shone on all three objects, which is going to heat up the most?
The black car interior heats up the most
If light actually were only a wave and I wanted to increase the energy of the light wave so that I had enough energy to knock the electrons free, what would I need to change in order to change the energy?
The brightness
Reflectivity
The characteristic of being capable of or producing reflection
Malleability
The characteristic of substances that allows them to be worked into desired shapes or drawn out into wires. It is the opposite of being brittle
What determines the color of objects?
The color of objects we see is determined by which colors they reflect and absorb. The ones that are not absorbed are reflected into our eyes (tomatoes do not absorb red)
Universe
The combination of the system plus surroundings
Ammonium nitrate (NH4NO3), a common fertilizer, is an ionic ally bonded substance involving two polyatomic ions, ammonium (NH4^4) and nitrate (NO3^-). Ammonium nitrate dissolves in a polar solvent such as water. Which of the following statements best describes what happens when this fertilizer dissolves in water?
The compound breaks up into the two oppositely charged ions. The ions do not break apart
Equilibrium
The condition where the forward rate and reverse rate of a chemical equation are the same, so there is no net change in the system. Energy is a minimum and entropy is a maximum
Transition state
The critical point that separates reactants from the products on a potential energy surface
Amplitude
The distance from the maximum point of the wave to the equilibrium point of the wave, and it is related to the energy of the wave
The motion of molecules is governed by which of the following?
The electromagnetic force, conservation of energy, and newton's laws of motion
Band gap
The energy difference between the bottom of the conduction band and the top of the valence band in semiconductors
Activation energy
The energy needed to allow a reaction to occur, break the bonds of the reactants, and allow the product to form
What is the best description of activation energy?
The energy that must be put into a system before a reaction can take place
A glass that contains a mix of ice and water stays at 0*C as long as there is ice left, even when the temperature of the room is much higher than 0*. Why?
The energy transferred from the room is increasing the potential energy of the water molecules
Activation entropy
The entropy associated with the formation of the transition state
When looking at the Brownian motion of dust particles in water, what would be observed if the temperature is increased?
The erratic motion of the dust particles increases.
Morphology
The form or structure of a material
If you change the wavelength of a sound wave, what else will change?
The frequency
Metallic luster
The high reflectivity or shininess of metals
This plot is a graph of average nucleon mass versus atomic mass for nuclei. What can you determine
The individual proton's and neutron's mass is smallest for atoms with a mass of about 50, and larger for atoms with very small or very big mass
How do the densities of an iron shaving and the entire Pacific Ocean compare?
The iron shaving is denser than the Pacific Ocean
What happens to the average kinetic energy of the water as heat is added to the ice?
The kinetic energy increases
A fast-moving molecule collides with a slow-moving molecule. The slow molecule speeds up while the fast one slows down. The extent to which their speeds change depends on their relative masses. This is an example of ___
The laws of conservation of energy and conservation of momentum
What happens to the valence electrons as the product (MgO) is formed?
The magnesium atoms' valence electrons are effectively transferred to oxygen.
A scientist is investigating how an unknown material responds to mechanical vibrations. During his studies he notes that compression waves travel through the substance, but shear waves do not. What can he conclude from this information?
The material could be a liquid or gas, but is not a solid
Products
The material(s) produced in a chemical reaction, written on the right side of the chemical equation
What happens to the melting temperature as the size of the molecule increases?
The melting temperature increases with size
What happens to the valence electrons as an ionic compound is formed?
The metal atoms' valence electrons are effectively transferred to non-metal.
Why do we say that the evidence for molecules using Brownian motion is indirect?
The molecules are too small to actually be seen with a microscope
Why do nearly all materials increase in density as they change state from a liquid to a solid?
The molecules in a solid are packed closer together
Both fission and fusion can result in a release of energy. Why?
The nuclei of atoms near the middle of the periodic table have the least energy and the nucleons with the smallest mass
The oxidation state of an atom refers to
The number of electrons gained or lost when an ionic bond is formed
What happens to the number of molecular orbitals as the number of atoms that come together increases?
The number of molecular orbitals increases
Wavenumber
The number of wavelengths in a particular length such as centimeters or meters (1//wavelength)
What illustration best describes the molecular orbitals in metals?
The one in the single solid block, with electrons seemingly random inside
Which of these is a saturated hydrocarbon?
The one that doesn't have a double or triple bond
For the reactions shown in the graph for the problem above, which reaction releases the most energy?
The one that goes the highest
In the graph, what reaction has the highest activation energy?
The one that goes up the highest and down the lowest
When some Ca(No3)2 dissolves in water, which picture best represents what the solution looks like? (Note, the balls are not meant to indicate charge or lack of charge.)
The one where Ca has separated from No, but N and o atoms are still bonded
Valence shell
The outermost, highest-energy set of orbitals in an atom
What can you conclude about the molecule regarding electronegativity?
The oxygen will be more negative than the carbon
System
The part of the world we want to isolate and study
When we observe Brownian motion, what do we actually see?
The particles jiggling about
If the light is made extremely dim, what happens to the pattern produced?
The pattern stays basically the same shape, but gets speckled, like it is made up of dots
Efficiency
The percent of energy that is converted into useful energy
A perfume bottle drops and shatters on the floor of a room. (An irreversible process has just occurred- the breaking of the bottle!) You observe that you can smell the perfume throughout the entire room a few seconds later. Which of the following explanations of this observation is correct?
The perfume's odor is caused by its molecules. Molecules of perfume in the liquid are in random motion. When the bottle breaks, the molecules can vaporize and spread throughout the room, mixing with the air in the room. The room with perfume molecules spread around it is more disordered than perfume molecules concentrated in a spot surrounding the broken bottle
If the average force increases, what happens to the pressure?
The pressure increases
diffraction grating
The process by which we can break up light into a spectrum
When you compare the mass of the products to the mass of the reactants in a fission reaction, what do you find?
The reactants have more mass
When you compare the band gap for a red and a blue LED, what is true?
The red LED has the smallest band gap
A window air conditioner is normally placed in a window so the hot air from the black blows outside. What would happen if the air conditioner were placed in the middle of a closed room and turned on?
The room would heat up because all of the energy absorbed by the air conditioner, both thermal and electrical potential, is released back into the room as thermal energy
A refrigerator is normally run with its door closed. What would happen if the refrigerator were placed in the middle of a closed room with its door open and turned on?
The room would heat up because all of the energy absorbed by the refrigerator, both thermal and electrical potential, is released back into the room as thermal energy.
Dipole
The separation of positive and negative charge in a polar bond or molecule
What happens to the spacing between the energy of one molecular orbital and the next one immediately above or below it as the number of atoms that come together increases?
The spacing between energy levels decreases
Chemical reaction rate
The speed at which the reactants are consumed and the products are formed
Which of the following types of electromagnetic radiation travels at the fastest speed?
The speed is the same for all of these
Reactants
The starting material(s) of a chemical reaction, written on the left side of the chemical equation
Which of these statements correctly describes the ranges of forces between charged nucleons in nuclear physics? "Short distances" refers to distances about the size of the diameter of a nucleon
The strong interaction is stronger than the electromagnetic interaction at all distances
Hydrogen bonds
The strongest of the intermolecular forces, higher melting/boiling temps
Universe
The system and surroundings put together
What happens to the temperature as heat is added when only one state of water is present?
The temperature increases
Why is temperature increasing while nitrogen is melting into a liquid, and then again while it is boiling, wrong?
The temperature should be constant while it is melting and boiling
What does half-life mean?
The time it takes for half of all the radioactive nuclei to decay
A reversible process does what to the total disorder in the universe?
The total disorder does not change
Mass number
The total number of protons and neutrons in a nucleus
If you compare metals with ionic compounds, what do they have in common?
Their melting temperatures are similar
Why does the density do this?
There is more mass in a smaller volume, so the density increases
What is the likelihood that the gases would gain the order they had if we left the system alone for a long time?
There is virtually no chance the gases would spontaneously unmix
Which of these is the least ordered?
Thermal energy
Why do natural unsaturated fats have a lower solidification temperature than saturated fats?
They have curved hydrocarbon tails keeping individual molecules farther apart.
What best describes how the oxygen molecules would behave if mixed with water?
They would dissolve poorly or not at all because they are not polar
How do molecules exchange energy?
Through collisions with the walls of the container and with each other
Law of increasing disorder (second law of thermodynamics)
Total amount of disorder in the universe either remains the same (reversible) or increases (irreversible)
Atomic mass or mass number
Total number of nucleons (protons or neutrons) that are found in the nucleus
Use the periodic table to decide if S is a metal or a nonmetal. Do the same for O. If these two form a compound, which of these characteristics will it show at room temperature?
Transparent gas
If two nitrogen atoms combine to make N2, what type of covalent bond exists between them?
Triple
A material that is made up of one type of molecule, where each molecule is made of 2 different types of atoms is still a pure substance
True
Baking soda and vinegar combine to make sodium acetate, carbon dioxide, and water. In this chemical reaction the reaction the reactants are the baking soda and vinegar
True
Energy and entropy are both involved in chemical reactions
True
In minerals, the underlying atomic structure gives rise to large-scale properties observable with the naked eye
True
Metals have a greater tendency than nonmetals to lose electrons
True
N2 has a triple bond and is a gas at room temperature. The triple bond is a very strong bond
True
Polar molecules dissolve easily in water
True
Quartz is a silicate that has strong bonds throughout its entire structure
True
The average kinetic energy of the molecules is related to the molecules' average speed
True
The average kinetic energy of the molecules is related to the molecules' mass
True
The temperature at which ice begins to melt to form a liquid and the liquid begins to freeze to form ice is the same
True
There are experiments that show that light has particle properties
True
There are experiments that show that light has wave properties
True
Unsaturated fats are considered an essential part of a healthy diet
True
True or false: It is energetically favorable for nonmetals to share electrons
True. Because of their strong attraction for electrons, nonmetals are attracted tot he electrons of other atoms
True or false: Polyatomic ions form crystals
True. Due to the charge on the ions, a network matter structure similar to a basic ionic-bonded structure results
True or false: Nonmetals have a large number of s- and p-type valence electrons relative to metals
True. Nonmetals have between four and seven of these kind of electrons while metals have only one to three
True or false: Nonmetal nuclei have a strong attraction for valence electrons
True. The high ionization energy of nonmetals is evidence for a strong electron-nuclear attraction
True or false: Forming a positive ion with a noble gase configuration (ns^2np^6) from a nonmetal requires a tremendous amount of energy
True. To form a positively charged ion with a noble gas configuration from a nonmetal means that up to seven valence s and p electrons may need to be removed. Since the ionization energy of each valence electron is high, the cost to remove that many would be exorbitant
Now imagine there is a detector at the slits which measures whether the photons travel through one slit or the other. What best represents the image on the screen?
Two narrow bands that are a little wider than the width of each slit
Fish that swim in the cold North Atlantic would have what type of fatty acid in their blood?
Unsaturated acids with lots of double bonds
P-type semiconductor
Vacancies for electrons
Molecules
Very tiny particles that make up matter
Opacity
Visible light is absorbed. It is the opposite of being transparent
Which of the following are types of electromagnetic radiation?
Visible light, ultraviolet light, x-rays, radio waves
Glass molecules have a higher mass than water molecules. Imagine a glass of water where both the glass and the water are at room temperature. Which type of molecules will have the highest average speed?
Water
The interference of light shows that light has ___ properties
Wave
What is the term for the width of a wave left to right?
Wavelength
Destructive interference (two waves of the same type)
Waves cancel each other out
Constructive interference (two waves of the same type)
Waves interact to give a larger wave
Diffraction
Waves spread out when they encounter corners or openings such as open doors
Refraction
Waves that bend *through* a medium- bending process that occurs when a wave travels from one medium to another is called refraction
Morphologies
Ways for the silicate ions to connect
Dispersion forces
Weak intermolecular attractions between nonpolar molecules arising from the formation of temporary dipoles
Dipole-dipole interactions
Weak intermolecular attractions between polar molecules
Dispersion forces
Weakest of all intermolecular forces, but also the most universal. Result of short-lived polarities of nonpolar atoms and molecules due to random fluctuations in electron density around the atoms
Fission
When a very large nucleus is bombarded by a slow-moving neutron and split into two smaller nuclei
Single bond
When atoms share a pair of electrons
Double bond
When atoms share two pairs of electrons
Equilibrium
When the forward rate of a reaction is equal to the reverse rate of the same reaction
Interference
When waves share the same space- different types of waves will not interact with each other
How do semiconductors change with increasing temperatures?
When you heat them up, semiconductors act more like metals
Are oxygen atoms balanced if a 2 is placed in front of water to make the following equation? H2 + O2 -> 2H2O
Yes
If the entropy associated with the contents of the refrigerator decreases, would the entropy of the surroundings need to increase in order for the law of increasing disorder to be obeyed?
Yes
Is the equation balanced now? 2H2 + O2 -> 2H2O
Yes
The hot air increases the temperature of the surroundings. Is this a process that increases the entropy of the kitchen?
Yes
The unbalanced equation is as shown: H2 + O2 -> H2O. Are the hydrogen atoms balanced?
Yes
In a nuclear power plant, the reaction rate is controlled using control rods to absorb some of the neutrons released by fusion. If you want to keep the reaction rate constant, what conditions do you need to have?
You absorb enough neutrons that for each atom that splits only one neutron splits another atom
If you make a wave very low amplitude and send it through a pair of slits what happens to it?
You still get the whole interference pattern, the wave is just not as big
How many double bonds exist between carbon atoms in these saturated fatty acids?
Zero
Nuclear fission is when
a large nucleus breaks apart into smaller pieces
What is the approximate range of the nuclear strong force? (In other words, what is the distance over which the strong force is significant?)
about the size of a nucleus
What happens to the overall entropy in the universe as this compound is formed?
entropy increases
Isotopes of an element are different atoms of the element that
have the same number of protons, but differ in mass number
Electronegativity on periodic table
increases from left to right, decreases from top to bottom (similar to the pattern for ionization energy, if you take out the noble gases)
Ionic compounds are formed between a metal and a
non-metal
Valence shell
outermost shell of an atom, when a single bond is formed, electrons are in the lowest energy orbital possible
The primary obstacle to controlled fusion reactions as a source of energy is
overcoming the electromagnetic repulsion of particles with like charges
Gamma decay
radioactive decay by emission of a gamma ray
Alpha decay
radioactive decay by emission of an alpha particle
Beta decay
radioactive decay in which an electron is emitted
The process known as nuclear fission is primarily responsible for
the energy produced by a nuclear reactor
The purpose of the control rods in a nuclear fission reactor is
to absorb neutrons, thus limiting the number of nuclei undergoing fission
