orgo lab
bond # Br
1
bond # Cl
1
bond # F
1
bond # H
1
bond #: O
2
What is the recommended order of measurements to report the most accurate melting point possible? Use slow heating to carefully observe melting. Use slow heating to confirm the careful measurement. Use quick heating to estimate the melting point.
2nd step 3rd step 1st step
bond # N
3
Wedges and dashes are used to indicate the ________ in a drawn structure. A wedge indicates that the atom or group is _______ and a dash indicates that the atom or group is ________.
3D shape coming out of the page going into the page
Bonds # C
4
What information does not need to be included on a chemical waste label?
A description of the experiment the chemicals were used for
*image discriptions* A beaker with funnel and arm B two way pipe c long extension C red pipe with white end D white end of red pipe E beaker c long neck and small circle bottom F regular beaker
A filter flask B distillation head C support rod D connector for general use E long-necked round bottom flask F erlenmeyer flask
Before adding a sample or solvent to a separatory funnel, what should you have in place?
A flask under the separatory funnel A stopcock in the closed position A funnel in the top of the separatory funnel
*image* two glass containers one labeled organic waste (C) and the other labeled aqueous waste (B), sitting in a plastic tray(D). Label A,B,C, and D
A funnel B primary container C waste label D secondary container
What types of IR sample preparation are appropriate to use between two salt plates?
A solid sample ground into a powder and mixed with mineral oil A pure, undiluted liquid sample A solid sample dissolved in an organic solvent, like dichloromethane
How can you remove the protein casein from a sample of non-fat milk?
Add acid to change the protein's tertiary structure, which triggers solid formation.
Why should you use a finely ground solid when determining the melting point of a sample?
Air pockets in a coarse sample could disrupt heat distribution. Uniform, small particles heat more consistently throughout the sample.
What are the best practices while sharing a lab balance with other students?
Alert your TA or instructor about any issues with the balance. Brush off any chemical dust around the balance after each use.
Identify the correct practices when setting up the condenser for a reflux system.
Align the flask so that the condenser is vertical. Grease the joint between the flask and the condenser.
A negative bromine test appears as
An orange solution
Identify the types of information that are necessary to communicate with emergency responders.
Any other hazards present in the lab, Any chemicals involved in an accident How the incident happened
When performing a melting point determination, how should you report your findings?
As a range from the temperature when melting starts to the temperature when it ends
Where should the tip of the thermometer be placed in a microscale distillation set-up?
At or slightly below the side arm of the distillation head
How should students prepare to use chemicals in the lab?
Become familiar with the chemicals to be used, including exposure or spill hazards. Locate the spill kits and understand how they are used.
Determine when to put on disposable gloves for work in the lab.
Before handling any glassware or chemicals for the experiment
What are lipids?
Biological molecules characterized by solubility in organic solvents
What are the best practices for safely handling waste in the lab?
Check labels or instructions before any disposal. Always wear appropriate Personal Protective Equipment
What should you do every time you are about to heat glassware on a hot plate?
Check that there are no cracks in the glassware Inspect the hot plate for frayed cords Ensure that the glassware is designed for heating
A method used to separate components of a mixture
Chromatography
What should you do after finishing work with a reagent bottle?
Close the bottle. Return the bottle to its proper storage location.
Close the side shields on the balance during reading.
Close the side shields on the balance during reading.
In a chromatography experiment, how do you identify the components of an unknown mixture?
Compare the Rf values of the mixture components to the Rf values of pure known compounds.
Identify the characteristics of a good recrystallization solvent.
Does not dissolve a sample well at low temperatures. Dissolves a sample well at high temperatures.
Before turning on the heat for a microscale distillation, what should you confirm about the set-up?
Existence of some opening in the set-up Presence of boiling chip in the sample Secure connections at the joints
What is the best course of action if solid material remains in the flask after the heating step of a recrystallization?
Filter the hot mixture.
What is the advantage of fluted filter paper shown compared with cone-shaped filter paper?
Fluted filter paper has more surface area suitable for collecting solid.
Which types of signs are posted to convey information about chemical storage?
Hazard signs such as "Flammable," "Oxidizer," and "Corrosive" National Fire Protection Association (NFPA) diamond
What information is necessary to review in order to be considered familiar with the Safety Data Sheet (SDS) of a substance?
Hazard warnings Personal protection and first aid recommendations Handling, storage, and reactivity information Identification and description of substance
Which procedure cannot be performed on a hot plate, requiring a Bunsen burner instead?
Heating a crucible to remove water from a hydrate
Wide melting point range
Impure sample of multiple compounds
What information is needed in order to be prepared for an emergency?
Location of lab phone and first aid contact info for emergency understanding of where to go should an emergency occur location of all exits
Why should Bunsen burners not be used when heating organic materials?
Many organic materials are flammable and could cause a fire.
When using a properly stabilized balance, how should you ensure that you get the most accurate mass reading possible?
Measure the mass of the sample at room temperature. Close the side shields on the balance during reading.
While setting up a beaker to boil a solution on a hot plate, you notice that the stirring is erratic and unstable. What should you do to stabilize the stirring solution?
Move the beaker to the center of the hot plate. Turn down the stirring speed
*image* diamond sign with blue, red, yellow and white squares.
NFPA diamond
What hazards are associated with naphthalene?
Naphthalene is flammable. Naphthalene is toxic. Naphthalene produces nauseating vapors.
When using a separatory funnel, you should burp the funnel.
Opening the stopcock when the flask is inverted during mixing
Identify the medical applications of aspirin.
Pain killer Fever reducer Anti-inflammatory agent Anti-coagulant
Narrow melting point range
Pure sample of a single compound
What is the first step for response to an emergency situation?
Remain calm and quiet, gather information, and assess the situation.
Which proposed chromatography experiment could best help determine whether the compounds are identical?
Repeat the original experiment with a different solvent system
A value that quantifies the distance traveled by a substance relative to the distance traveled by the solvent
Rf
If crystal growth does not start on its own after the solution in the flask returns to room temperature, identify the best ways to promote this process.
Scratch the bottom of the flask gently with a stirring rod. Add a bit of solid as a seed crystal.
Which steps are necessary for cleaning a spill involving broken glass?
Stop the spread of the spill. Soak up any spilled liquid with absorbent material. Pick up large pieces of glass with gloved hands.
The balls in a modeling kit representing different elements are often distinguished by color. However, there are other ways to identify the elements. Beyond color, what differences do you expect between the atoms of carbon, nitrogen, and oxygen in a modeling kit?
The arrangement of holes in the atoms The number of holes in the atoms
Under what conditions should a student inform the instructor of a lab injury?
The instructor must be informed of all laboratory injuries.
When melting mixtures of compounds, what is the eutectic composition?
The mixture composition with the lowest melting point
What are the concerns presented by overheating a distillation to a dry flask?
The remaining solid residue might contain explosive peroxides. The empty glassware might heat quickly, igniting vapors from the distillation.
Why might activated carbon be added to a sample during the recrystallization process?
To absorb impurities causing the recrystallization solution to have an incorrect color
What is the purpose of a drying agent in the work up of an organic reaction?
To absorb small amounts of water in an organic solution
What is the purpose of stirring a solution while it is being heated?
To help evenly distribute heat throughout the solution
In lab, you may need to evaluate the odor or smell of a chemical. What is the best way to smell a chemical sample?
Use your hand to gently waft the smell toward you.
What is the main precaution to take if a Gas Cylinder sign is present in the lab?
Visually check that the gas cylinder is restrained but keep a safe distance from it.
Determine the safest option in the lab if you need your vision to be corrected.
Wear corrective glasses or lenses under your safety goggles for the whole experiment, but always check with your TA or Instructor for your school's policy
Determine when you should remove your goggles in the lab room.
When everyone in the room is done handling any chemicals or glassware
When should you start a new chemical waste container in the lab?
When the contents of the current container are a couple inches below the brim of the container
Many reflux procedures involve a required length of time for the reflux to occur. When should you start timing the reflux for the procedure?
When the reflux ring stabilizes in the condenser
Hot filtration is a technique in which the mixture is heated and all the glassware is also heated for the filtration. When should you use the technique of hot filtration?
When you are separating a slightly soluble solid from an insoluble solid
What is the last step of any spill cleanup procedure?
Wipe down the affected area with detergent and water.
Biuret test shows the presence of
a tripeptide or larger peptide
Mixtures are characterized by two fundamental properties: Each of the substances in the mixture retains its ________ identity. Mixtures are separable into these components by _________ means.
chemical physical
The frequency at which a nucleus absorbs and resonates with a magnetic field
chemical shift
While pulling an empty beaker off the shelf at the beginning of lab, it slips out of your hand onto the floor.
closed toe shoes
A positive bromine test appears as
colorless solution
What are the substances making up a mixture called?
components
When using a water-cooled condenser, the water should _________ the condenser. To make this happen, the water should flow in at the __________ and should flow out at the __________.
constantly moving bottom part top part
In general, which characteristics are necessary for a location to be suitable for chemical storage?
cool, dark and dry
This is the process of separating a liquid from a solid (sediment) by gently pouring the liquid from the solid so as not to disturb the solid.
decantation
After drying an organic solution, what methods can be used to remove the drying agent from solution?
decanting
Shielding can be ____________ by the presence of more electronegative groups around the nucleus.
decreased
how to find percent by mass of a compound
divide the recovered material by the mixture amount X 100
Identify the precautions to take with exits in the lab.
do not block a door with an EXIT sign Locate the exists prior to the start of lab
In general, when hydrocarbons like oil are added to water, the two liquids __________ because hydrocarbons are _________ and water is __________.
do not mix non-polar polar
Iron(III) chloride can be used to assess the purity of aspirin synthesized from salicylic acid. Iron(III) chloride ___________ react with aspirin because the reaction requires _______ which is present in ____________.
does not a phenolic functional group salicylic acid but not aspirin
peptide bond
double bond O and NH
1-chloro-1-fluoroethane
double bond coming from the left c Cl and F on the right (2)
number of signals: benzene
double bond ring (1)
The end of the NMR spectrum far from the reference signal
downfield
Storage of solvents or other materials in a desiccator
drierite
Do not form hydrogen bonds amongst themselves and have higher vapor pressure
esters
Notable for their pleasant fragrances
esters
Their reactions with base are known as saponifications
esters
*image* six peak line with a double bond of O on the 3rd peak and a -O- on the fourth peak. name the molecule
ethyl proanoate
How can a solid dissolved in water be separated from the water?
evaporation
Which process is used to separate soluble compounds from insoluble compounds?
extraction
Determine whether each statement applies to washes or extractions. Moves desired compound from one layer to another Leaves desired compound in its starting layer Moves impurities from one layer to another Often involves a reaction in one of the layers Leaves impurities in their starting layer
extraction wash wash extraction extraction
*image* green square with an eye, plus sign and shower
eye wash station
T/F: Beverages are allowed in lab as long as they are in containers with lids.
false
T/F: Chewing gum is okay in the lab as long as you don't blow bubbles.
false
This is the process of separating a solid from a liquid by means of a porous material.
filtration
Identify the equipment best suited for extinguishing each type of fire. clothing fire small benchtop fire large fire on floor
fire blanket, flip over beaker, fire extinguisher
Which types of hazards can a fume hood help protect the user against?
fires, explosions and fumes
Identify the safety equipment designed to deal with each emergency listed. cuts or minor burns fire on a person chemicals on clothes large fire on the benchtop chemicals in eyes
first aid kit fire blanket safety shower fire extiniguisher eyewash station
1,2,3-trichloropropane
five peak line c Cl on both ends and in the middle (2)
2,2-dichlorobutane
four peak line c Cl on the top and bottom of the second peak (3)
*image* diamond with a red outline and a black cylinder in the middle
gas cylinder
Most chemicals can be cleaned up with a general spill kit, but a few chemicals require specialized spill procedures. For each substance listed, determine whether a general spill kit is sufficient or if a specialized spill kit is needed. acetone hydrofluoric acid phosphoric acid mercury methanol
general special general special general
If you drop or break glassware in lab, first__________ Then, ___________ Finally, place all that material into the_________
get thick gloves or dustpan carefully collect all the broken glassware broken glass container
PPE. While picking up a buret, an unknown solution left by a previous solution drips onto your hand.
gloves
Determine which items of personal protective equipment (PPE) you will likely use in a general chemistry lab.
gloves, lab coat and goggles
PPE. While checking on a stirring solution, the solution splashes up towards your face.
goggles
Changing gloves often will minimize the spread of chemicals. To properly remove gloves, first, ______________ and then, ___________. Then insert ___________ between the interior edge of the second glove and the skin, and remove the second glove.
grasp the exterior of one glove with a gloved hand peel off the first glove a bare finger
Microscale glassware kits include connectors to fit the smaller glassware. The black connectors should be used when _________ are present. Otherwise, the tan connectors can be used. The connectors can combine different pieces of glassware or components _____________
high boiling aromatics from the same kit
Other amino acids are polar and are generally referred to as _________.
hydrophilic
Experimental melting point is below literature value
impure sample of multiple compounds
What are minor components in a mixture called?
impurities
When preparing for work in the fume hood, be sure to gather all necessary tools, glassware, and chemicals ____________ to minimize the number of times the hood sash is raised and lowered. Work as much as possible in the _________ of the work surface to keep the area tidy and promote air flow. If you need to step away from the experiment to obtain another item, ________ the sash during this time.
in advance middle lower
The area of a signal that corresponds to the number of nuclei at that frequency
integration
At the melting point, the solid form of a substance ________ the liquid form of the substance.
is in equilibrium with
In order to dissolve a chemical sample in a recrystallization solvent, add the room-temperature solvent _______ in an Erlenmeyer flask on a hot plate. Turn on the heat, starting at ___________. Using a ________, add additional solvent from a second container on the heat source. Swirl the sample flask after each addition, and try to add _______ in order to dissolve the solid.
just until it covers the sample a low setting and increasing gradually pipet as little solvent as possible
While transferring a solution from a flask to a beaker, the solution accidentally spills down the front of the lab bench.
lab coat
After a recrystallization, a pure substance will ideally appear as a network of ____________. If this is not the case, it may be worthwhile to reheat the flask and allow the contents to cool more __________.
large crystals slowly
Distillation is the separation of multiple ______ components based on their different _________. As the mixture is heated and the first component ___________, its _________form travels through the distillation set-up and __________into a different container
liquid boiling points boils, vapor condenses
Olive oil is a ________, so it contains mostly ___________ fatty acids. These fatty acids have ________ intermolecular forces and ______ melting points.
liquid unsaturated inhibited lower
Modeling kits often offer parts to make two different types of models. A ball-and-stick model uses __________ connections as bonds and are used to focus on the ___________ A space-filling model uses _________ connections as bonds and are used to focus on the ____________.
longer properties of the molecules bonds shorter molecules overall shape
when given the molecules structure as a picture and they ask the signal number corresponding what do you look for?
look at the corresponding bonds (if the H is connected to 3 diff elements its 4 signal, )
Radiation in the infrared (IR) range is __________ in energy than visible or ultraviolet light. When a molecule absorbs IR radiation, __________ within the molecule and each __________ creates a band in the molecule's IR spectrum.
lower bonds vibrate absorbed wavelength
Which of the following would not be helpful in separation a mixture of sand and salt?
magnet
Most of the __________ people encounter in everyday life consists of ___________ of different substances.
matter mixtures
Aspartame is the methyl ester of a dipeptide made of phenylalanine and aspartic acid. What are the expected products of the hydrolysis of aspartame?
methanol, phenylalanine and aspartic acid
To insert a thermometer into an adapter, use __________ to prepare the thermometer. Then, hold the thermometer _________ the adapter and _______ the thermometer into the adapter.
mineral oil close to slowly turn
Dissolve a substance in a ________ amount of hot solvent. Allow the solvent to cool, precipitating the ________ while ________ remain in solution. ___________ the mixture to collect the pure substance.
minimal substance, impurities filter
combinations of two or more substances.
mixtures
The substance that carries the components of a mixture
mobile phase
how to determine if a number is possible Rf value
must be between 0 and 1. no negatives
To see amino acids on a developed chromatography paper or plate, you can react it with _________ after __________.
ninhydrin letting the paper dry
axial stricture
one big element pointing up
To build a single bond in a ball-and-stick model, you need to use ________.The resulting bond should _____. To build a double bond, you need to use_______. The resulting bond should _________
one connection rotate two connections not rotate
In general, amino acids are non-polar if ____________are present. Such amino acids are also referred to as _________.
only carbon and hydrogen hydrophobic
To prepare a sample in a capillary tube for a melting point determination, gently tap the tube into the sample with the________ end of the tube down. Continue tapping until the sample ________. Then, with the _________ end of the tube down, tap the sample down slowly or ___________ to move the sample down faster. Finally, make sure that you can see _________ in the magnifier when placed in the melting point apparatus before turning on the heat.
open is a couple millimeters high closed drop the tube into a longer tube some or all the solid
*image* diamond with a red outline and an O on fire
oxidizing chemical
The separation of the components of a mixture is based upon the fact that each component has different________ properties. The components of a mixture are separated based on their______ properties.
physical physical
When using the Tare function on a balance, start by _______ Then, _________ to cancel out that mass. Finally, __________ and record the mass of your sample.
placing the glassware on the balance press zero add your sample
Denaturing is the process of interrupting a protein's structure so that it no longer functions. Which level of structure is NOT affected by denaturing a protein?
primary
The sequence of amino acids
primary structure
Whereas _______ substances have ________ compositions, the composition of _________ can vary.
pure fixed mixtures
Experimental melting point is close to literature value
pure sample
Interaction of multiple of protein units
quaternary structure
Amino acids can be either polar or non-polar based on their
r group
*image* green square with a person shower and plus
safety shower
Contain no carbon-carbon double bonds
saturated fatty acids
More likely to be solid at room temperature
saturated fatty acids
Small 3D features determined by hydrogen bonding
secondary structure
Determine where to dispose of each type of waste. syringe tips unused solid reagent broken flask titrant solution
sharps container solid waste container box lined with puncture resistant bag nalgene bottle with cap
Move to the safety shower if you spill hazardous chemicals on your _______________. Stand under the shower and ___________ the lever. Remove clothing and continue flushing the area for __________.
skin or clothing, pull, 15 mins
Sublimation is a phase change from _______ to _________. The __________ phase is not present in this change.
solid gas liquid
What characteristics should a good sample for melting point determination have?
solid phase thoroughly dry small particles
Which property is the basis of the purification technique recrystallization?
solubility
The appearance of multiple peaks for a single nucleus due to neighboring nuclei
splitting
When heating a solution to boiling on a hot plate, start by _______. Then, turn the heat to _____________ to start. If necessary, __________ after waiting about ten minutes without seeing boiling.
starting and stabilizing the stir function the medium heat setting turn up the heat setting
The substance to which the sample is bound at the start of an experiment
stationary phase
A solid mixture is heated. One component transitions directly between solid and gas.
sublimation
Overall 3D shape of a protein
tertiary structure
The IR spectrum of a solid can be taken by dissolving it to create a solution. An appropriate solvent is ___________ because its IR stretches are _____________.
tetrachloromathane only in the fingerprint region
Which layer should contain the carboxylate in a two-layer mixture of water and an organic solvent, like diethyl ether? added a base
the aqueous layer
How to calculate the Rf value
the distance traveled by the compound divided by the distance traveled by the solvent front
N-terminus
the end of a polypeptide or protein that has a free amino group (N)
C-terminus
the end of a polypeptide or protein that has a free carboxyl group (O)
Which layer should contain the carboxylic acid in a two-layer mixture of water and an organic solvent, like diethyl ether?
the organic layer
An azeotrope is a mixture that has ___________ composition in the ______. Therefore, an azeotropic mixture ________ be separated by distillation.
the same gas and liquid phases cannot
Determine the best way to deal with each of the following items that may dangle into the way during lab work. flowy sleeves long necklaces long hair long earrings loose bracklets
tie back or secure remove tie back or secure remove remove
Steric strain occurs when parts of molecules are _________ and their electron clouds ______ each other. Molecules with steric strain are _______ than those without strain.
too close together repel less stable
T/F: Food items should not be brought into the lab.
true
T/F: Tobacco products of all kinds are prohibited in lab.
true
newman structures: eclipsed
two lines poking through top and all hydrogens at bottom
The composition of homogeneous mixtures is ______________.
uniform
Contain carbon-carbon double bonds
unsaturated fatty acids
More likely to be liquid at room temperature
unsaturated fatty acids
The end of the NMR spectrum close to the reference signal
upfield
A shielded nucleus appears further ___________ whereas a deshielded nucleus appears further_________ in an NMR spectrum.
upfield, downfield
The composition of heterogeneous mixtures is ______________.
variable
A positive Biuret test appears as
violet solution
What should you do every time before you leave the lab?
wash your hands remove your labcoat remove your goggles
Which species will have an IR spectrum?
water vapor methane carbon dioxide
Identify examples of classes of lipids.
waxes, fats, oils
acidic solutions
will have a + sign
basic solutions
will have a - sign
neutral solutions
will have both + and -
trans structures
will have both ends pointing out
Cis structures
will have one end pointing up and the other end pointing out
equatorial structures
will only have one big element pointing out
When you are done using the glassware from a kit, what should you do?
wipe down the glassware place glassware back in original kit
Which is NOT a good source of information about the hazards that affect waste disposal in a chemistry lab?
your lab partner
The molecules that will be combined to form an ester are a
carboxylic acid and alcohol
What functional groups are present in all amino acids?
carboxylic acid and amine
Usually have a sour odor
carboxylic acids
1,1-dichloroenthane
cartoon chicken foot c Cl on top and bottom (2)
Form hydrogen bonds amongst themselves and have lower vapor pressure
carboxylic acids
Their reactions with base are known as neutralizations
carboxylic acids
1. Surround the area with_________ then cover the spill. 2. Scoop up the material and place in a____________ 3. Place the bagged waste in a__________ 4. Wipe down the area with_________
absorbent material plastic bag solid waste container detergent and water
how to find percent yield
actual yield/theoretical yield x 100
Once the vacuum filtration set-up is complete, start by __________ in the filter funnel. Then, _________ the mixture ___________.
adding a small amount of water slowly decant into the middle of the filter paper
Multiple reagents or changes can denature a protein. Which listed change will NOT denature a protein?
adding water
Identify the term that matches each definition. The front vent of a fume hood, which helps maintain proper air circulation A characteristic that describes substances that evaporate readily, producing large amounts of vapors The glass panel in front of the fume hood that shields the user from fumes and other hazards The horizontal, flat area of a fume hood upon which experiments are carried out
airfoil volatile sash work surface
If an unknown compound has a moderately intense, wide peak in the 3200-3400 cm-1 region, what functional group is likely present?
alcohol
The bromine test shows the presence of
alkenes
newman structure staggered
all spread out evenly
Hand lotion consists of _________ of substances that are soluble in _________. Lotions are designed to improve the __________ of the skin.
an emulsion water and oil texture and apperance
When drying an organic solution, start by transferring the solution to _________ or a test tube, depending on the amount. Then, add _________ of the drying agent and __________ to determine if you added enough drying agent. Continue __________ until the solution is dry.
an erlenmeyer flask a pea-sized amount swirl the flask adding small amounts
Removal of small amounts of water from a polar solvent
anhydrous calcium chloride
In an NMR experiment, shielding refers to the reduced impact of the ____________ on a nucleus due to the presence of ________ around the nucleus.
applied magnetic field, electrons
Aniline involves an amine, which is a ___________ functional group. When an aqueous acid solution is added to an organic solution including aniline, the aniline appears in the _________ layer in its _________ form. Then, a base is added to _________ the aniline.
basic aqueous protonated reconstitute
You should set out support, like a cork ring or clamp, _______ the glassware from a glassware kit to place the glassware in and to stop it from _________ Thoroughly check that the glassware is ________ and that it does not have any _________before using it.
before removing rolling clean cracks
A negative Biuret test appears as
blue solution
Removal of visible pockets of water from an organic solvent
brine wash
correct structure of aspirin
carbon ring with double bond O and OH coming from top and a side piece of -O-, double bond O and CH3
chiral center
carbon with multiple branches
Aspirin was formed to reduce the irritation of salicylic acid. However, aspirin can still disturb the stomach. Which functional group in aspirin is responsible for stomach irritation?
carboxylic acid
