Chem 1152 lab final

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addition polymer

A polymer formed as monomers link together without forming a byproduct.

condensation polymer

A polymer formed as monomers link together, forming a small molecule as a byproduct.

ester formation-esterification

Carboxylic acids react with alcohols

formic acid

HCOOH

A polymer produced through a condensation reaction, with applications ranging from clothing to packaging.

Polyethylene terephthalate

A rigid, brittle polymer used in disposable food containers. The backbone of the polymer contains phenyl rings.

Polystyrene

A rigid polymer used often in construction materials. The structure contains a halogen.

Polyvinyl chloride

Titration

Process of slowly adding a solution to react with another solution and determine the concentration of one of the solutions based on the reaction between them

Amino acids can be either polar or non-polar based on their____________

R groups

What is the first step for response to an emergency situation?

Remain calm and quiet, gather information, and assess the situation.

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 minutes

acetal

a primary carbon with two -OR groups and a hydrogen atom

Which metal is responsible for the color change in a Benedict's test?

copper

Sucrose

glucose + fructose

Lactose

glucose + galactose

Maltose

glucose + glucose

In order to work as an emulsifying agent, the soap needs to have both a ___________ region and a _________ region.

hydrophobic hydrophililc

Determine where to dispose of each type of waste: syringe tips

sharps container

ionization of carboxylic acids in water

weak acids in water RCOOH + H2O → RCOO- + H3O+

Which tests show can be used to show that a phenol is present?

-Acidity test -Iron(III) chloride test The acidity test reacts a base with phenols to deprotonate them and easily dissolve them. In the iron(III) chloride test, a phenol becomes a ligand on iron and changes its color.

What are the best practices for safely handling waste in the lab?

-Always wear appropriate Personal Protective Equipment. -Check labels or instructions before any disposal.

Identify the types of information that are necessary to communicate with emergency responders.

-Any chemicals involved in an incident -How the incident happened -Any other hazards present in the lab

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.

What should you do after finishing work with a reagent bottle?

-Close the bottle. -Return the bottle to its proper storage location.

What information is needed in order to be prepared for an emergency?

-Contact information for emergency personnel -Location of lab phone and first aid kit -Location of all exits -Understanding of where to go should an emergency occur

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 -Gas Cylinder sign

What should you do every time before you leave the lab?

-Remove your gloves. -Wash your hands. -Remove your labcoat, if you are wearing one.

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.

Fill in the words to complete the steps in the process of recrystallization. 1. Dissolve a substance in a _________ amount of hot solvent. 2. Allow the solvent to cool, precipitating the ___________ while __________ remain in solution. 3. ________ the mixture to collect the pure substance.

1. minimal 2. substance; impurities 3. filter

What information does not need to be included on a chemical waste label?

A description of the experiment the chemicals were used for

hemiacetal

A functional group that contains a carbon atom bonded to one -OR group, one -OH group, an alkyl chain, and a hydrogen atom.aldehyde + alcohol

indicator

A reagent added to the analyte solution that changes color when the reaction is complete

noncompetitive inhibitor

A substance that reduces the activity of an enzyme by binding to a location remote from the active site, changing its conformation so that it no longer binds to the substrate.

Identify effective techniques for accurate pipet use. Select all that apply. A. Measure liquid by aligning the meniscus with the volume line. B. Do not let liquid enter the pipet bulb or pump. C. Use the pipet bulb to force the last drop out of the tip. D. Leave any air bubbles in a pipet that occur after drawing up liquid.

A. Measure liquid by aligning the meniscus with the volume line. B. Do not let liquid enter the pipet bulb or pump

Identify factors that impact the function of an enzyme. A. Temperature B. Concentration of substrate C. pH D. Presence of inhibitor E. Concentration of enzyme

A. temperature B. concentration of a substrate C. pH D. presence of inhibitor E. Concentration of enzyme

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

What functional groups are present in all amino acids? Select one or more: A. Amide B. Carboxylic acid C. Alcohol D. Amine

B. Carboxylic acid D.Amine

Determine where to dispose of each type of waste: broken flask

Box lined with puncture resistant bag

What are the reasons to determine the melting point of a sample in a melting point apparatus? Select one or more: A. Conversion of the solid sample to liquid B. Removal of impurities from the sample C. Identification of an unknown sample D. Assessment of the sample's purity

C. Identification of an unknown sample D. Assessment of the sample's purity

Determine whether the phrase describes carboxylic acids or esters: Their reactions with base are known as neutralizations

Carboxylic acids

A student removes a chemical sample from a reagent bottle to be used in an experiment. What should he do with any excess chemical remaining from this sample after the experiment is complete?

Check and see if anyone else can use the chemical. If not, discard in the proper waste container.

In a TLC 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.

What is a protease? Select one: A. An enzyme that breaks down a protein into individual amino acids B. A protein consisting of a chain of amino acids C. A component of foods such as fruit juices D. All of the above are correct.

D. All of the above are corrrect

Which of the following names identifies an enzyme? Select one: A. substrate B. phosphoglucose C. glycolysis D. dehydrogenase

D. dehydrogenase

Seliwanoff's Test

Determination of ketoses -distinguishes between ketopentoses and ketohexoses -Ketohexoses (6-carbons) will form a cherry red color, while ketopentoses (5-carbons) will give colors that are blue to green to gray. The color should be noted within the first 5 minutes for a positive test for ketoses

Which statements accurately describe soap? Select one or more: A. Soaps work in solutions of any pH. B. Soaps are both hydrophobic and hydrophilic. C. Soaps react with ions in hard water to create a precipitate. D. Soaps are a mixture of fatty acid salts and glycerol. E. Soaps should be weakly alkaline in solution

E. Soaps should be weakly alkaline in solution. C. Soaps react with ions in hard water to create a precipitate. B. Soaps are both hydrophobic and hydrophilic

Determine whether the phrase describes carboxylic acids or esters: Notable for their pleasant fragrances

Esters

Determine whether the phrase describes carboxylic acids or esters: Their reactions with base are known as saponifications

Esters

Buret

Glassware that allows a solution to be precisely and slowly added to another solution

A flexible polymer used in the manufacturing of grocery bags. The molecular structure is (C2H4)n

High-density polyethylene

Acetal Formation

In acidic conditions, an aldehyde or ketone will react with two molecules of alcohol to form an acetal

Barfoed's Test

Monosaccharide determination distinguishes between monosaccharides and disaccharides -A positive test for monosaccharides is again the brownish-red Cu2O but it needs to appear in the first 4-5 minutes. Disaccharides will eventually hydrolyze in the heat and acidic conditions and also give a brownish red color

What effect do restriction enzymes have on DNA?

Restriction enzymes cleave DNA at specific sequences into fragments.

How should spill cleaning materials be discarded?

Seal in a labeled plastic bag, then place in the solid waste container.

Analyte

Solution of an unknown concentration that has another solution slowly added to it

Titrant

Solution of known concentration that is slowly added to a solution of unknown concentration

Benedict's test

Test for reducing sugars. -If a reducing sugar is present, the reagent changes from blue to red copper precipitate.

Absorbance

The amount of light absorbed by a sample

actual yield

The amount of product experimentally produced when the chemical reaction is carried out

theoretical yield

The calculated amount of product under ideal conditions

percent yield

The comparison of the experimental amount of product to the calculated amount

Under what conditions should a student inform the instructor of a lab injury?

The instructor must be informed of all laboratory injuries.

Transmittance

The passing of light through a sample

Gel electrophoresis

The separation of nucleic acids or proteins, on the basis of their size and electrical charge, by measuring their rate of movement through an electrical field in a gel.

What features of a carbohydrate usually indicate that it is a reducing sugar? Select one or more: A. There is a hemiacetal in the ring form. B. The sugar is a disaccharide. C. Only acetals are present in the sugar. D. There is an aldehyde in the chain form

There is a hemiacetal in the ring form. There is an aldehyde in the chain form.

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

when should you 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

Endpoint

When the required amount of one solution has been added to the second solution to complete the reaction

Determine whether the phrase describes carboxylic acids or esters: Form hydrogen bonds amongst themselves and have lower vapor pressure

carboxylic acids

Determine whether the phrase describes carboxylic acids or esters: Usually have a sour odor

carboxylic acids

The anionic end of soaps is attracted to ________ in hard water. The resulting compound is an insoluble precipitate known as soap scum.

cations

Molisch test

determines whether carbohydrates are present -The 𝛼-naphthol reacts with the furfurals formed from carbohydrates with 5 carbons or more to yield a purplish or violet colored compound. This color is a positive indicator for saccharides of 5 carbons or more.

In general, alcohols __________ when mixed with water because the __________ in alcohols can_____________ with water.

dissolve O-H bonds hydrogen bond

Rf=

distance travelled by mixture component/ distance travelled by mobile phase

Protease

enzyme that breaks down proteins -proteins that act as enzymes which break down other proteins into amino acids

Determine whether the phrase describes carboxylic acids or esters: Do not form hydrogen bonds amongst themselves and have higher vapor pressure

esters

Identify the safety equipment designed to deal with chemicals in the eyes

eyewash station

saponification is the process of making soaps from _____________. The reaction is a type of _________ that uses the addition of a __________ to release the ___________________, which is the soap.

fats or oils hydrolysis strong base deprotonated fatty acid

Identify the safety equipment designed to deal with fire on a person

fire blanket

Identify the safety equipment designed to deal with a large fire on the bench top

fire extinguisher

Identify the safety equipment designed to deal with cuts or minor burns

first aid kit

Monosaccharides

glucose, fructose, galactose

A substance that limits or stops the activity of an enzyme

inhibitor

soaps do not work in ______ pH solutions

low

Enzymes are biological catalysts that enhance the rate of a reaction by

lowering the activation energy

A polymer is a macromolecule made of many repeated subunits, known as ______________

monomers

Determine where to dispose of each type of waste: titrant solution

nalgene bottle with cap

Bial's test

pentose confirmation Distinguishes between pentoses and hexoses -With pentose, the test yields a blue or green solution whereas with hexose, the test yields a muddy brown solution. Other simple carbohydrates do not react.

Identify the safety equipment designed to deal with chemicals on your clothes

safety shower

Determine where to dispose of each type of waste: unused solid reagent

solid waste container

A compound that has a reaction an enzyme speeds up

substrate

disaccharides

sucrose, lactose, maltose

Native structure of an enzyme

the Specific arrangement maintained by intermolecular forces needed for an enzyme to work

Which process would restore a fatty acid from a soap?

the addition of an acid

When a protein is hydrolyzed, ........

the bonds between amino acids are cleaved and the protein is broken down into individual amino acids.

When a protein is denatured, ..........

the protein loses its shape.

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 __________________________

three-dimensional shape coming out of the page going into the page.

Identify the three types of reversible inhibitors.

uncompetitive- A molecule that binds to the enzyme-substrate complex. noncompetitive- A molecule that limits the effectiveness of the enzyme without binding to the active site. competitive- A molecule that binds to the enzyme active site instead of the substrate.

A Seliwanoff's test resulting in a red solution indicates the presence of ______________

a ketose

ester naming

alcohol-yl acid-oate

Which functional group on the structure of p-aminophenol will react with acetic anhydride to produce acetaminophen?

amine

Proteins are examples of natural polymers, made from _________________________ monomers

amino acid

reducing sugars involve __________

an aldehyde that can be oxidized

A Seliwanoff's test resulting in a light pink solution indicates the presence of _____________

an aldose

In general, amino acids are non-polar if only ___________________ are present. Such amino acids are also referred to as hydrophobic.

carbon and hydrogen

What elements make up a carbohydrate?

carbon, hydrogen, and oxygen in a 1:2:1 ratio

neutralization of carboxylic acids

carboxylic acid + strong base --> carboxylate (salt) + H2O


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