Organic Chemistry Set

Réussis tes devoirs et examens dès maintenant avec Quizwiz!

name the functional group R - OH

Alcohol (-ol)

name the functional group R - COH the O is double bonded to carbon (a carbonyl)

Aldehyde (al)

describe an oxidizing agent

An oxidizing agent has to be reduced...has to take electrons from the other atom. This means the reaction of that agent will be written as a reduction reaction. The most positive potential will represent the most potent oxidizing agent. This is as the table is written. So, the most potent oxidizing agent is found at the bottom left.

name the functional group R-CO-O-COR' as in carboxylic acid have R'COO- replaces the -OH R and R' may be same/different

Anhydride (-oic anhydride)

The polarity of a molecule: A .depends on steric relationships of the substitutuents B .depends on both the bond polarities and the geometry C . depends only on bond polarities and electronenegativity D .depends only on molecular geometry

A strong band on an IR spectrum is seen at 1750cm-1, the absorption could represent a(n) A .alcohol B carboxylic acid C . aromatic ring D .ether

A strong broad band on an IR spectrum is seen at 3350cm-1. The absorption could represent a(n) A . ether B . alcohol C . ketone D . ester

An amino acid with this side chain, CH3CH2C(CH3)H—, would be found at/on the A . outside surface of protein B . inner regions of protein C . active site of acid catalysis D . active site of basic catalysis

An atom which has hybrid orbital(s) at 1800 from each other has A . one hybrid orbital B . two hybrid orbitals C . three hybrid orbitals D . four hybrid orbitals

CH3CH2— OH:What is the suffix of the functional group of this molecule? A .-yne B . -ol C .ether D .-nitrile

Each of the following is a correct description of an oxidation EXCEPT A .an increase in the oxidation state B . an increase in the number of hydrogens C occurs at the anode D .a loss of electrons

Each of the following is a steroid EXCEPT A .estriol B .serotonin C .progesterone D .aldosterone

Histones are ____________ charged proteins due to the presence of excess ___________ amino acids. A . Negatively, Acidic B . Positively, Basic C . Negatively, Basic D . Positively, Acidic

In the IR spectrum, this is the approximate location of the C-O bond which have a moderately strong signal may be found at this location, given in wave numbers, in an IR A .700 B .1100 C .1200 D . 1650

Increased torsional and steric strains result from this conformation of cyclohexanes. A . chair B . boat C . axial D . equatorial

Of the following, the most stable radical is A . primary B . benzyl C . secondary D . methyl

SP2 orbitals may form A . Pi bond B . Sigma bond C . Both of the above D . Neither of the above

The alcohol group A . is non-polarized B . forms hydrogen bonds C . is basic in water solutions D . acts a Lewis Acid

The atoms attached to a double have this geometry: A . Linear B . Planar C . Tetrahedral D . Pyramidal

The base strength of an amine will __________when the number of __________groups attached to the nitrogen increases A . increase, electron withdrawing B . decrease, electron withdrawing C . decrease, electron donating D . cannot make this prediction

The oxygen on the alkyl group of an ester, comes from the oxygen A . of the hydroxyl group on the carboxylic acid B . of the alcohol C . of the carbonyl oxygen D . of water

This is the site of attack for nucleophilic addition. A .the zeta carbonyl oxygen B .the beta carbon C . the carbonyl carbon D .the alpha carbon

This reaction is alkenes or double bonds. A .nucleophilic substitution B . electrophilic substitution C .electrophilic addition D .electrophilic replacement

What is the correct suffix for ester? A .-al B .-amide C .-oate D . correct suffix not listed

In an IR spectrum, the Aromatic absorptions are best described as A . broad B . sharp C . weak D . medium (strength)

Match the average chemical shift in an NMR C13 for this group: Aromatic group A . 35 ppm B . 40 ppm C . 45 ppm D . 135 ppm

Match the average chemical shift in the C13 NMR for this group: C=C(alkene) A . 10 ppm B . 30 ppm C . 45 ppm D . 125 ppm

what are Isoelectric points (IPs)

IPs are the pHs at which the AA or protein is neutral (has no net charge). This does not mean there are no charges on the molecules; it just means the charges sum to zero.

aldehydes and ketones react with alcohols to produce ____ and _____

hemiacetals and hemiketals

electron donating (decreases/increases) shielding and increases field strength which results in (upfield/downfield)

increases, upfield

what are the x and y axis for a mass spectroscopy graph

intensity (y-axis and the number of particles striking per area) versus the m/z ratio (as the x-axis), and this is the MS graph or spectrum.

The pKa's of the acid groups are less/greater than the pI. The pKa's of the basic groups are less/greater than the pI of the AA

less, greater

alcohols are more/less soluble than alkanes and alkenes why?

more because of hydroxyl groups increasing the polarity and it allows for hydrogen bonding with H20

alkenes are more/less acidic than aklanes why why not?

more acidic because alkenes have pi bonds which are electron hungry and when a proton is removed, the pi bond absorbs some of the negative charge stabilizing the conjugate base

aldehydes are slightly more/less acidic than ketones

more but both aldehydes and ketones are less acidic than alcohols

crystallization is based on the fact that pure substances form crystals (less easily/more easily) than impure substances

more easily

the more double bonds there are, the more/less polar a molecule becomes and the more/less soluble it becomes

more, more

what is an alpha carbon?

a carbon than is attached to the carbonyl carbon ...the next carbon is the beta and the next is gamma and so on

An NMR spectrum is a plot of____ versus the______

absorbance, frequency

The ammonium ion (because of the charge and not because of the alkyl and R group substitution) acts as an acid/base

acid

-using LiAlH4 (lithium aluminum hydride) in the first step and acid in the second to convert an ____to an ____

acid, alcohol

using B2H6 (diborane) in the first step and acid in the second to convert an ____to an _____

acid, alcohol

carboxylic acids will behave as an acid/base or as substrate in a electrophilic/nucleophilic substation reaction

acid, nucleophilic *its stereochemistry makes it susceptible to nucleophilic attack by nucleophiles

what is an electrophile

an electron loving species so it will have a partial positive charge

Remember that the more/less polar compounds are more tightly absorbed by the stationary phases. They will be the slowest/fastest (or last/first) to move from the stationary phase.

more, slowest, last

when dealing with nitrogen containing compounds the 3 things you should consider are 1. they may act as a lewis acid/base donating their lone pairs of electrons 2. they may acts as electrophiles/nucleophiles where the lone pair of electrons attacks a positive charge 3. nitrogen can take on a fourth bond (becoming positively charged)

base, nucleophiles

elimination occurs when nucleophiles behaves as a (acid/base)

base_ it abstracts a proton rather than attacking a carbon

ammonia and amines act as weak bases/acids by doing what

bases, donating electrons

The bond between the two glucoses is called ______ glycosidic bond.

beta- 1, 4

In cellulose, the glucoses are bound by ______ glycosidic bonds to form the polymer

beta-1,4

NMR is used to determine_______ skeletons

carbon

what is an enolate

carbon anions: alpha carbon anions (en from alkenes and ol from alcohol)

elimination reactions always result in what kind of bonds

carbon carbon double bonds

Carboxylic acids are a combination of a _____bond and an ______

carbonyl, alcohol

all carboxylic acid derivatives hydrolyze to give what

carboxylic acid

benzoic acid is a benzene ring with ______ attached to the R position

carboxylic acid

To make an anhydride, a _____ is used.

carboxylic acid ( or carboxylate ion)

name the functional group R-COX

carboxylic acid chloride *as in carboxylic acid a halide (X), usually -Cl, replaces the -OH

name the functional group R-COX as in carboxylic acid a halide (X), usually -Cl,replaces the -OH

carboxylic acid chloride (-oyl chloride)

alkynes produce _____ ___ when undergoing ozonolysis

carboxylic acids

what does it mean to be an aliphatic acid

carboxylic acids where the R group is an alkyl group

Adehydes are converted to alcohols (primary) and ketones to alcohols (secondary) by what 2 methods

catalytic hydrogenation or NaBH4 (sodium borohydride)

in regards to benzene when an electron withdrawing group such as hydroxyl is in the r position then it activates/deactivates the ring and directs any new substituents to the (meta/ortho/para) position (s)

deactivates, meta position *halogens are an exception to the rule- they are electron withdrawing, but they direct new substituents to the ortho/para positions

when a carboxylic acid loses Co2 the reaction is called _______

decarboxylation * the energy of activation is usually high making the reaction difficult to carry out but the energy of activation can be lowered when the beta carbon is carbonyl because either the anion intermediate is stabilized by resonance or the acid forms a more stable cyclic intermediate

the most/least reactive alkenes in electrophillic addition are the most thermodynamically stable this is because they have the lowest activation energy when forming carbocations

most

tertiary amines form what by reacting with alkyl halides

quaternary ammonium salts

f both optical isomers are present in the same concentration, there is no rotation of plane-polarized light and the mixture is called a ____

racemate (racemic).

what are the final products of decarboxylation

tautomers

Vapor Pressure of any liquid varies directly as the _____:

temperature: vp is proportional to temperature

ultraviolet spectroscopy (UV)?

the molecular characteristic used is electron transitions . The molecule is irradiated with different continuous wavelengths of the UV spectrum. The UV light will cause an electron to move from an occupied molecular orbital to a higher unoccupied molecular orbital. This transition,ground to excited state , absorbs energy.

name the functional group R - H

alkane (-ane)

name the functional group R2C = CR2 where R may be a carbon group or a H

alkene (-ene)

heats of hydrogenation can be used to measure the stability of _______

alkenes

isoelectric point

(given by pI) which is the point at which the molecule is not charged. The pI corresponds to a specific pH. If the pH of the medium is greater than the pI, then the molecule will be negative. If the pH of the medium is less than the pI, then the molecule will be positive.

in a combustion reaction, whats the equation for the number of H2O produced where n is the number of carbons

(n + 1)H2O produced. "n" is the number of carbons.

A nucleus is deshielded (i.e., made to absorb at a lower field strength or to the left on the spectrum) in two ways which are what?

*First, if the circulating electron cloud decreases, the opposing magnetic field decreases. An absorbing nucleus (e.g.,1H) attached to an electronegative atom would lose "electron density" to that atom. The opposing electron magnetic field would be decreased, the nucleus would be deshielded, and the nucleus' absorption would be downfield or to left. *The second method of deshielding is by electron currents set up in double bonds. The structure of these currents is such that the applied field is augmented. This allows the nucleus to come into resonance at a lower value of Hoand to the left on the spectrum.

Stereoisomers are further broken down into optical isomers, which differ by having the presence of what? and cis-trans isomers, which differ owing to the presence of a what?

-an asymmetric carbon atom, -ring or a double bond in the molecule.

Some key locations of carbons:Halides (0-80) w/ greater electronegativity toward 80 Saturated (8-60) with 3H,2H,1H attached toward 60 Triple-bond C (65-85) Double-bond C (100-150) Single-bond O (40-80) Double-bond O (170-210) Aromatic C (110-160) Single-bond N (30-65)

...

ppm = parts per million = x/106 = x/1,000,000 ppb=parts per billion = x/109 = x/1,000,000,000 ppt = parts per trillion = x/1012 = x/1,000,000,000,000

...

The main reaction of all of the carboxylic acid derivatives is carbonyl nucleophilic substitution. what are the steps

1. A nucleophile attacks the carbonyl carbon, forming a tetrahedral intermediate (TAP) 2. elimination of a leaving group, which is usually the functional group that determined the type of derivative (i.e., the alkoxy for the ester, the amine for the amide, the halide for the acyl halide, etc.) *The first step, attack of the nucleophile on the carbonyl carbon, is usually the rate-determining step.

what are the tree steps for extraction?

1. add a strong acid and shake. the acid protonates bases like amines in the organic layer making them polar. the polar amines dissolve in the aqueous layer and are drained off 2. add a weak base. the base deprotonates only the strong acids like carboxylic acids making them polar. the polar carboxylic acids dissolve in the aqueous layer and are drained off 3. add strong base. the strong base reacts with the rest of the acids (hopefully all weak acids like phenol) these acids dissolve in the aqueous layer and are drained off

what are the steps involved in condensation of ketones

1. amine acts a nucleophile attacking the electron deficient carbonyl carbon of the ketones 2. the ketones undergo nucleophilic addition 3. an acid catalyst protonates the product to form an unstable intermediate 4.. the intermediate loses water and a proton to produce either an enamine or an imine *if the original amine is secondary then it has no proton to give up so the ketone must give ups its alpha proton as a result, an enamine is produced if the original amine was primary then it gives up its proton to form an imine

what are the steps in aldol condensation

1. base catalyzed reaction the base abstracts an alpha hydrogen leaving an enolate ion 2. the enolate acts as a nucleophile and attacks the carbonyl carbon to form alkoxide ion. the alkoxide ion is a stronger base than a hydroxide and thus removes a proton from water to complete the aldol * the aldol is very unstable and easily dehydrated by heat or a base to become an enal and the enal is stabilized by double bonds

The three steps in the acetoacetic ester synthesis of substituted ketones are

1. enolate formation with a base of the alpha hydrogen between the two carbonyls; 2. nucleophilic attack of the carbon enolate ion on the alkyl halide to result in alkylation (which may be mono- or disubstitution); and 3. the conversion of the ester to the carboxylic acid by acid ester hydrolysis and then heating of the beta-ketoacid to result in decarboxylation and formation of the substituted ketone.

what are the steps in electrophillic addition

1. hydrogen halide, bronsted lowry acid, creates a positively charged proton which acts as an electrophile 2. the newly formed carbonation picks up the negatively charged halide ion *first step is the slow step and determines the rate

the 4 key features of the Huckel rule to determine if a compound is aromatic are:

1. the molecule is planar 2. the molecule is cyclic 3. each atom of the cyclic structure has a p orbital 4. The number of electrons in the ring must be 4n + 2, where n = 0, 1, 2, 3, ... , and is the number of electrons in the "p" orbitals.

the wave number for Carbon single-bond oxygen is about _____.

1100

the wave number for Carbon double-bond oxygen is about ______.

1750

Peak B is split into three peaks, so its neighbor has_____ hydrogens.

carbohydrates can be thought of as carbon and water , for each carbon atom there are ____ hydrogens so for every carbon there will be ___ water molecule

2, 1

For 13C NMR spectrum Chemical Shift is 0 -_____ ppm instead of 0 -____.

200, 10

For each asymmetric carbon (n), there are ___ optical isomers.

2^n

Peak A is split into four peaks, which means there are_____ equivalent hydrogens (assume for simplicity) as neighbors.

the wave number for Aromatic/multiple bond hydrogens are slightly greater than _____.

3000

the wave number for aliphatic (not aromatic) are slightly less than ____

3000

the wave number for Oxgyen-hydrogen (OH) is about _____and is broad if hydrogen-bonded.

3500

what is a mess compound

A meso compound represents two potential enantiomers that are superimposable, and therefore identical, and decreases the number of distinct molecules from two to one, because of a plane of symmetry of the molecule.

describe a reducing agent

A reducing agent will be oxidized. The reaction must be written so that the atom is losing an electron. These reactions are written as reductions which means the atom is taking an electron. So, the table must be reversed to show oxidations. This means the atoms at the top right would be most like to give up their electrons and be oxidized. So, the most potent oxidizing agents should be at the top right of the table.

Wittig reaction?

A ylide is formed by reacting a triphenyl (Ph) phosphine with an alkyl halide (RX) in a reaction analogous to the reaction of an amine with an alkyl halide. The ylide then reacts with the carbonyl to form the betaine intermediate, which decomposes to the final product, a compound with a carbon-carbon double bond where the carbon-oxygen double bond was initially. So, a carbonyl is converted to an alkene .

A C—C-I group may have its absorption at this location in an IR spectrum. A . 700 B . 1100 C . 1200 D . 1650

A compound with 2 methyl groups on the 5 carbon of the longest chain would be named as A . 5,5-dimethyl B . 5-methyl C . 5-dimethyl D . 2,2-dimethyl

A phospholipid is made of each these EXCEPT A . cholesterol B .saturated fatty acid C .unsaturated fatty acid D .nitrogen containing phosphorus compound

All are the same in stereoisomers but different in structural isomers EXCEPT A . total number and types of atoms B . functional groups C . carbon skeleton D . all of the above are different in structural isomers

An amine which is uncharged A . will have a free pair of electrons which act as a Lewis base B . will undergo nucleophilic addition C . is in a fixed configuration D . will act as an acid

At a pH somewhat less than the pI, an amino acid will have a(n) _________ amino group and a(n) __________ carboxyl group. A . positive, neutral B . negative, neutral C . neutral, positive D . neutral, negative

Basic amino acids, compared to other amino acids, will have A . higher isoelectric points B . lower isoelectric points C . charged side chains D . sulfur

CHΞCH:What is the suffix of the functional group of this molecule? A . -yne B . -ol C . ether D . -nitrile

Fats are composed of__________fatty acids and __________. A . 3, glycerol B .2, glycerol C .3, phospholipid D .2, phospholipids

Fatty acids are__________ chained,__________numbered __________ . A . long, even, carboxylic acids B .short, even, ketones C .long, odd, carboxylic acids D .short, odd, ketones

This conformation has minimal torsional and steric interactions in cyclohexane. A . chair B .boat C .axial D .equatorial

A. in the chair form, the bonds and the substituents are as far from each other as possible.

For the best separation of two liquids in a simple distillation, each of the following is important EXCEPT A . all the following are important B .heating the mixture slowly C .boiling points are widely separated D .impurity liquid present in small amounts

How does this molecule act in acid-base reactions? R—Cl A . acts as a base only B . acts as a base and an acid C . acts as an acid only D . acts as neither an acid nor base

If a triple bonded atom is directly attached to the chiral carbon, in determining absolute configuration, you must A . count the atom 3 times in determining its priority B . count the substituents of the atom 3 times in determining its priority C . count the atom only once D . all multiple bonded atoms should be ignored

In order to have chirality, the carbon or nitrogen must be A . sp3 hybridized B . sp2 hybridized C . sp hybridized D . any of the above

Name this compound CH3CH(CH2CH3)CH2COCH2CH3 A . 5-Methyl-3-heptanone B . 2-Ethyl-3-hexanone C . 3-Nonanone D . tert-Butyl hexanone

On the IR spectrum, this is the fingerprint region. It is the region which can "fingerprint" and identify a specific compound by comparing it to know spectra. But, there are no specific functional groups identifiable. may be found at this location, given in wave numbers, in an IR A .700 B .1100 C .1200 D . 1650

Rotation of plane polarized light by an optical isomer is called A . Optical rotation B .Polarization C .Diffraction D .Interference

Sequence of amino acids is the key feature of this structure A .primary structure B .secondary structure C .tertiary structure D .quaternary structure

The beta and alpha isomers interconvert by the process called A . Mutarotation B . Epimerization C . Tautomerization D . Internal migration

This can only form single bonds A .sp3 orbital B .sp2 orbital C .sp orbital D . all of these

This is the major reaction for aromatic molecules...usually a hydrogen is replaced by another atom A . electrophilic substitution B .nucleophilic substitution C .electrophilic addition D .nucleophilic addition

This is the major reaction for aromatic molecules...usually a hydrogen is replaced by another atom A .electrophilic substitution B .nucleophilic substitution C . electrophilic addition D .nucleophilic addition

This is the most stable conformation. A . staggered B .eclipsed C .gauche D .alternated

This is the reaction for carbonyl compounds especially carboxylic acid derivatives A .nucleophilic substitution B . electrophilic substitution C .electrophilic addition D .electrophilic replacement

This reaction (step) does NOT result in a final product of the reaction. A . initiation step B . propagation step C . termination step D . all of these

This requires a polar solvent and it can also be protic. Nonpolar solvent would slow the reaction A .SN1 B .SN2 C .both D . neither

This spectroscopy identifies functional groups. A . infrared spectroscopy B .mass spectroscopy C .NMR spectroscopy D .UV spectroscopy

This type of bonding has electron density between the nuclei. A . characteristic of sigma bonds B .characteristic of pi bonds C .characteristic of both sigma and pi bonds D .characteristic of neither sigma nor pi bonds

This type of reaction may result in a racemic product. A . SN1 B . SN2 C . both D . neither

Unmodified proteins are exclusively made of A . amino acids B .glucose C .fatty acid D .glycerol

What are isomers? A . Compounds having the same molecular formula but different molecular structures B . Compounds having different molecular formulas but the same molecular structures C . Compounds which cannot be superimposed upon each other D . Only for compounds with no double bonds

What is the correct suffix for aldehyde? A .-al B .-amide C .-oate D . correct suffix not listed

What is the formal charge on N in NH3? A . 0 B . -3 C . -2 D . -1

What is the name of this compound? CH3-CO2H A . acetic acid B . benzoic acid C . formic acid D . malonic acid

When a molecule like Br2 adds to a carbonyl compound, A .the electrophilic component adds to the alpha carbon in the enol form B .the electrophilic component adds to the alpha carbon in the keto form C . the nucleophilic component adds to the carbonyl carbon in the enol form D .the nucleophilic component adds to the carbonyl carbon in the keto form

Where is the absorption, given in wave numbers, of the aldehyde hydrogen (-COH) which is a sharp weak absorption A .2750-2850 B . 2850-2960 C .3020-3100 D .3300

Which is a true statement about Steroids? A . sex hormones B . diverse biological functions C . cell membranes D . energy storage

Which of the following molecules has a triple bonded oxygen? A . Carbon monoxide B .Carbon dioxide C .Bicarbonate ion D .Ozone

Which of these rings has a planar ring(s) conformation? A . cyclopropane ring B . cyclobutane ring C . cyclopentane ring D . cyclohexane ring

A solid substance may be considered to be impure if any of the following occur EXCEPT A .melting occurs over a narrow range B . a broad range of the melting point C .a depression of the melting point D .an eutectic point exists

A. A narrow temperature range over which melting occurs is a good sign of a pure solid.

A phospholipid will be soluble in A .polar and non-polar solvents B . polar solvents C .non-polar solvents D .acid solvents

A. A phospholipid has a nonpolar end, the fatty acids, and a polar end, the nitrogen-phosphorus component. This allows it to be soluble in either polar, the nitrogen-phosphorus end, or nonpolar, the fatty acid end, solvents.

This type of molecule will have two hydrogens bonded to the nitrogen. A .primary B .secondary C tertiary D . none of these

A. A primary amine has two hydrogens

Which group of similar mass compounds will have the lower boiling points? A .alkane B . aromatic C .alkene D .all will be identical if the masses are equal

A. Alkanes will have the lowest boiling points as there are only dispersive forces acting.

A tertiary amine has __________hydrogen's attached to nitrogen. A .no B .one C .two D . three

A. Another set of commonly used terms is primary, secondary, and tertiary. Primary means there is one carbon group (R) attached to the carbon containing the functional group. Secondary means two carbon groups (R) are attached to the carbon containing the functional group. Tertiary means three carbon groups (R) are attached to the carbon containing the functional group. For nitrogen (N) compounds the terminology is the same. But, there is a quaternary nitrogen compound which has four groups attached to the nitrogen. The nitrogen will have a positive charge. So, a tertiary amine will have three carbon groups and the unpaired electrons. There will be no hydrogens.

At a pH above pI, the amino acid will lose its A . Hydrogen B .Carbon C .Carboxyl group D .Amino group

A. As pH rises, the solution is more basic and will neutralize hydrogens/hydrogen ions

The naturally occurring amino acids have (are) A . L series B .D series C beta aminos D .alpha carbonyls

A. Compared to the Fisher projections for carbohydrates, which are the D series, this means the amino group is to the left in the standard projection

This reaction is faster in solvents which have higher dielectric constants. A . SN1 B .SN2 C .both D .neither

A. Dielectric constants are related to electric charges. The higher the dielectric constant of a solvent, the better that solvent can support ions. This reaction has a carbocation as an intermediate and would be helped by higher dielectric constant solvents.

If a hydrocarbon compound has only two triple bonds and n carbons, the general formula will be A . CnH2n-6 B .CnH2n+3 C .CnH2n-2 D .any of the above are possible

A. Each triple bond reduces the number of hydrogens expected by 4 hydrogens. Since there are two triple bonds, the deficit in hydrogens will be 2x4=8. The formula for a fully saturated, no ring hydrocarbon is CnH2n+2. This means the 2n+2 must be 2n+2-8=2n-6.

What causes water to have a relatively high boiling point (BP)? A .Hydrogen bonds between water molecules B .Hydrogen bonds between hydrogen and oxygen within water molecules C .Covalent bonds between hydrogen and oxygen within water molecules D .Ionic bonds between the water molecules

A. Hydrogens bonds are strongest of the intermolecular bonds. It takes increased energy, and increased temperature, to break them.

During reactions, if an intermediate__________it will be __________likely to form, and the reaction via this pathway is __________likely. A . can become aromatic, more, more B. can become aromatic, less, more C .loses it's aromaticity, more, less D .loses it's aromaticity, less, more

A. If a molecule meets the criteria for aromaticity, it means the molecule is more stable and less reactive to electrophilic attack than corresponding double bonds. This stability is evident as the composite bond energies of the aromatic compound is less (more negative) than the corresponding bond energies of a similar nonaromatic compound. If a molecule can achieve aromaticity by losing or gaining electrons (i.e., forming a cationic or anionic intermediate), it will easily do so. This means intermediates, or transition states, that result in aromaticity will be more likely to form. Intermediates and transition states that destroy aromaticity will be less likely to form. This means if the intermediate can achieve an aromatic state, it will form faster. If there are alternative products and one is aromatic and the other is not, the aromatic will be more stable and more likely to form.

When a non-electrolyte is added to a pure solvent to form a solution, A .the boiling point increases and the vapor pressure decreases B .the boiling point increases and the vapor pressure increases C . the freezing point decreases and the vapor pressure increases D .the freezing point decreases and the boiling point decreases

A. If the VP of the solution is lowered, the BP is elevated. As more particles go into solution, the higher the BP of the solution becomes.

The ring form of a carbohydrate A .is formed by the nucleophilic attack of an hydroxyl group on a carbonyl group B . destroys one of the asymmetric centers of straight chain form C .is the least abundant form when compared to the straight chain D .does not interconvert with the straight chain once it is formed

A. In a six carbon carbohydrate, it is usually the -OH on the 5th carbon which attacks the carbonyl carbon.

Separation depends directly on polarity of molecules. A . chromatography B .electrophoresis C .fractional distillation D .recrystallization

A. In most chromatography set-ups, a solvent is used either nonpolar or beginning with the most nonpolar. Then the nonpolar solutes/molecules move through the system the fastest.

Separation depends directly on polarity of molecules. A .chromatography B .electrophoresis C .fractional distillation D .recrystallization

A. In most chromatography set-ups, a solvent is used either nonpolar or beginning with the most nonpolar. Then the nonpolar solutes/molecules move through the system the fastest.

Primary and secondary alcohols may be converted to alkyl halides via a (n) ___________ reaction using ______________. A .SN2, SOCl2 B . SN2, HX C .SN1,PBr3 D .SN1, HX

A. PBr3 is also used. The OH is converted to a good leaving group by bonding with the P or the S. This is then displaced by the halide ion in the SN2 reaction yielding the alkyl halide

Half reactions are written as reduction reactions. In a table, the potentials are listed from the smallest to the largest (from negative to positive) from top to bottom A . if the half reaction is multiplied by 2, the potential is unchanged B .the most potent reducing agents are on the right side of the table at the bottom C .the most potent oxidizing agents are on the left side of the table at the top D .the half reactions with a negative potential will spontaneously proceed in the direction written

A. Since the potentials are potential differences, the multiplication of the stoichiometric equation will not affect the potential difference and the reduction potential is unchanged.

Electrophilic additions to aromatic rings do NOT occur because A . the disruption of the aromatic ring structure would occur B only one atom can add to an aromatic double bond C .the double bond of the aromatic ring is poorly electrophilic D .the ring only undergoes nucleophilic reactions

A. Substitution is preferred over electrophilic addition, as for a regular double bond, because of the great stability of maintaining the aromatic ring. Aromatic double bonds are less susceptible to electrophilic attack than regular double bonds. The positive character of the electrophile must also be enhanced. This is accomplished by using Lewis acids such as AlCl3.

If a molecule is optically active, and the chiral carbon is undergoing the attack in a SN1 reaction, the resulting product will be A .a racemate B .optically active with the same configuration C . optically active with the opposite configuration D .unable to determine

A. The SN1 is called substitution nucleophilic monomolecular. This is a first-order reaction, and there is one species in the rate equation and in the critical step. The mechanism of the reaction is (charges are ignored in the discussion which follows): first step (slow):

For an E2 reaction, the leaving group is __________ to the abstracted proton. A . anti B .syn C .gauche D .eclipsed

A. The best orientation is both in the same plane on opposite sides of the carbon-carbon single bond

For a given external pressure, the effect of raising the vapor pressure is to A . lower the boiling point B .raise the boiling point C .have no effect on the boiling point D .not able to determine without more information

A. The boiling point is the temperature at which the vapor pressure of the liquid equals the external pressure. If the vapor pressure is higher, then it is closer to the external pressure and less of a temperature is needed to make them equal. So, whenever the vapor pressure is increased, the temperature at which that liquid will boil is lowered

t any given temperature for ideal liquids A .the composition of the vapor is richer in the component with the lowest boiling point B . the composition of the vapor is richer in the component with the highest boiling point C .there is an azeotrope present at the boiling point of the lower boiling point liquid D .there is an azeotrope present at the boiling point of the higher boiling point liquid

A. The component of a solution with the lowest boiling point will have the highest vapor concentration at any given temperature. *The higher the boiling point, the less will be in the vapor phase, above the liquid, at any given temperature.

The enolate ion formed when the alpha carbon, to the carbonyl group, loses a hydrogen A .is a nucleophile and can attack electropositive atoms B .is a nucleophile and can attack electronegative atoms C . is an electrophile and can attack electropositive atoms D .is an electrophile and can attack electronegative atoms

A. The enolate ion is a negative ion with a free pair of electrons. The free pair of electrons and negative charge makes it an excellent nucleophile. Nucleophiles attack positive centers.

The melting points of unsaturated fatty acids tend to be _______________ saturated fatty acids. A . lower than B .higher than C .the same as D .unrelated to

A. The fatty acids with double bonds, unsaturated, will have lower melting points and may be liquids at room temperatures rather than solids.

An amine which is uncharged A . will have a free pair of electrons which act as a Lewis base B .will undergo nucleophilic addition C .is in a fixed configuration D .will act as an acid

A. The free pair of electrons will serve as a nucleophile and a Lewis Base:

For an organic compound, the heat of combustion is __________ and is a measure of the __________ of ring compounds. A .negative, strain energy B . positive, strain energy C .negative, combustibility D .positive, combustibility

A. The heat of combustion is the amount of heat released when a substance completely burns in the presence of oxygen: The heat above is the heat of combustion...it is negative enthalpy. The greater its value, the greater the energy per CH2, or in the case of cyclic compounds, the greater the ring strain present. If combustion is not complete, a product is CO instead of or in addition to CO2.

n this ring, orbitals are bent to minimize ring strain. A . cyclopropane ring B .cyclobutane ring C .cyclopentane ring D .cyclohexane ring

A. The molecule is still planar, but the orbitals instead of being 60o, which would be angle of 3-membered ring, has orbitals with directions greater than this.

Which is the best descriptor of a Furanose? A . a five member ring sugar B .the carbonyl carbon C .shows ring forms of sugars D .optical isomer of glyceraldehyde which is basis of the most natural sugars

A. The pyranose is the six-membered ring and the furanose is the five-membered ring.

LiAlH4 followed by acid will convert carboxylic acid derivatives to A . alcohols or aldehydes B .ketones C .carboxylic acids D .alkanes

A. The reduction product with LiAlH4 will be the aldehyde first and this may be reduced further to the alcohol.

For the peptide, Gly—His—Lys—His, the free amino end is at A .the Gly B . the last His C .can be at either D .is at neither

A. The standard nomenclature is to write the peptide such that the amino free end is at the left-most amino acid. The carboxylic end would then be to the right.

A steroid hormone acts by A . activating DNA by binding to nuclear receptors B .activation of G proteins C .activation of cAMP D .activation of inositol triphosphate

A. The steroid, being lipid soluble, can cross membranes. It goes to the nucleus where it binds with receptors which become transcription factors.

With this side chain, HOOC—CH2CH2—, an amino acid would best be described as A .acidic B basic C .neutral-non-polar D .neutral-polar

A. This is a carboxylic acid and is acidic. As a side chain on an amino acid, it would make it polar.

With this side chain, HOOC—CH2—, an amino acid would best be described as A . acidic B .basic C .neutral-non-polar D .neutral-polar

A. This is a carboxylic acid and would be an acidic side group. It would make the amino acid acidic. This is aspartic acid.

Example of a bicyclic ring is A .Norbornane B .Decalin C .Penicillin D . All the above

A. This is a ring system with a bridge which connects the rings.

For the R group in the structure: R—COOR', which is the correct sequence from least reactive to most reactive in terms of primary (P), secondary (S) or tertiary (T) structure of the carbon of the R bonded to the carbonyl carbon, in terms of acyl nucleophilic substitution? A .T,S,P B .T,P,S C . S,P,T D .S,T,P

A. This is an Sn2 type nucleophilic reaction. The size of the R group can inhibit and slow down the incoming nucleophile. So, the smaller the group, the faster the reaction. So, primary is faster than secondary is faster than tertiary. *The tertiary is the slowest reactor in the nucleophilic acyl addition *The primary is the fastest reactor in the nucleophilic acyl addition

An Hydroxyl (hydrogen bonded) group absorption in an IR spectrum is best described as A . broad B .sharp C .weak D .medium (strength)

A. This is one of the broadest and strongest absorptions in the IR spectrum

Where is the approximate absorption, given in wave numbers, of the Aldehyde (—CHO) hydrogen in the IR spectrum? A . 2750-2850 B .2850-2960 C .3020-3100 D .3300

A. This is sharp weak peak at this location.

What is the Anomeric carbon? A .the carbonyl carbon B .shows ring forms of sugars C .optical isomer of glyceraldehyde which is basis of the most natural sugars D .shows straight chain configurations of sugars

A. This is the anomeric carbon. It can either be a ketone (ketose) or aldehyde (aldose). When a straight-chain goes to the ring-form, the anomeric carbon forms a hemiacetal bond. When two monosaccharides join together at the anomeric carbon, an acetal is formed.

The initial step in the acid catalyzed esterification of a carboxylic acid is__________followed by the __________ A .protonation of the carbonyl of the acid, nucleophilic attack of the carbonyl carbon by the oxygen of the alcohol B . nucleophilic attack of the carbonyl carbon by the oxygen of the alcohol, protonation of the carbonyl of the acid C .protonation of the oxygen of the alcohol, nucleophilic attack of the hydroxyl oxygen of the acid on the alcohol D .nucleophilic attack of the hydroxyl oxygen of the acid on the alcohol, protonation of the oxygen of the alcohol

A. This is the first step. This makes the carbonyl carbon even more susceptible to attack by the nucleophile (the O of the alcohol).

Type of hybrid associated with the inversion of nitrogen compounds. A .sp3 orbital B . sp2 orbital C .sp orbital D .all of these

A. This is the hybrid form of ammonia. One of the sp3 orbitals is occupied by a free pair of electrons. This allows a flipping with the electron pair "up" or "down".

Which conformation of cyclohexane is more stable? A . Chair conformation B .Boat conformation C .They are equal because there is no ring strain in either D .Cannot determine unless know the substituents and their locations

A. This is the more stable conformation because there is less torsional and steric strains present.

This level of protein structure is found in all peptides and proteins: A . primary structure B .secondary structure C tertiary structure D .quaternary structure

A. This is the sequence of amino acids...this is found in all of the levels of structure.

Which is the nucleophilic part of water? A .the oxygen B . the hydrogen C .the free electron pair on the hydrogen D .the free electron pair on the oxygen

A. This would be nucleophilic...it is the free pair of electrons

All are steroids EXCEPT A . thyroxin B .aldosterone C .progesterone D .estriol

A. Thyroxin is a modified amino acid with iodine.

A phospholipid and a triglyceride differ in all EXCEPT A .containing glycerol B .having a charged nitrogen/phosphate group C .being asymmetric D . being bipolar

A. Triglycerides and phospholipids both have glycerol as a key component. *Only phospholipids have this *Only the phospholipids are chiral. *Only the phospholipids are bipolar

Which bond is stronger: pi or sigma? and why? A . Sigma B .Pi C .Both are same D .Depends on the atoms

A. because the electron density is between the nuclei

In the aldol condensation, one carbonyl acts as a(n)__________ and one acts as a(n) __________. A . nucleophile, electrophile B .nucleophile, nucleophile C .electrophile, electrophile D .any combination of the above

A. he aldol condensation has one carbonyl reacting with another. The alpha carbon of one, in the enol form with its negative character, will act as a nucleophile. The carbonyl carbon of the other, with its positive character, will act as an electrophile accepting the nucleophile. *One carbonyl acts as a nucleophile at its enol position, and the other as a electrophile at its carbonyl carbon

The no. of carbon-carbon double bonds in a saturated fatty acid is A . 0 B .1 C .2 D .2 or more

A. saturated fats have no double bonds while unsaturated fats have at least one

Which of the following will result when a tertiary alcohol reacts with H2SO4? A .intermediate carbocation formed and alkene results B . intermediate carbocation formed and substitution of OH results C .no intermediate carbocation formed and alkene results D .no intermediate carbocation is formed and substitution of OH results

A. tertiary alcohol reacts with a strong acid to dehydrate and form an alkene. The mechanism is an E1 elimination with the formation of an intermediate carbocation. There may be a rearrangement to a more stable carbocation. The most stable double bond (most substituted) will form.

When the tetrahedral addition product to the carbonyl carbon loses __________, a __________is formed in the location where the original __________ was located. A .water, double bond, carbon-oxygen double bond B .water, single bond, carbon-carbon single bond C . carbon dioxide, double bond, carbon-oxygen double bond D .carbon dioxide, single bond, carbon-carbon single bond

A. the tetrahedral addition product may be a product, but usually water is lost to form a double bond between the nucleophile and the carbonyl carbon: c is incorrect because Carbon dioxide is not lost from the tetrahedral addition product. The nucleophile forms a double bond at the carbonyl carbon where the double-bonded oxygen was located

Covalent bonds are the main determinate of this structure: A .primary structure B .secondary structure C . tertiary structure D .quaternary structure

A.The sequence of amino acids is the primary structure. These sequence depends upon the covalent bonds of the peptide (amide) type.

name the functional group R-CONH2 as in carboxylic acid have -NH2 instead of -OH R groups may replace H's on N

Amide

amino acids are made from __ and ____

Amino acids (AA) are amines and carboxylic acids.

A single compound which has asymmetric carbons but is NOT optically active. A . structural (constitutional) isomer B . meso compound C . optical isomer D . enantiomer

The solubility of a substance A . can be determined by theoretical considerations B . is not equal to its solubility product C . will be the same in most solvents D . will always increase as the temperature increases

This grouping includes optical isomers and cis-trans isomers. A . structural (constitutional) isomer B . stereoisomers C . conformational isomers D . enantiomers

This is the major reaction for carboxylic acid derivatives. There is initially a nucleophilic addition to the carbonyl carbon and then the originial substituent is displaced...eg, the hydrolyis of an ester by hydroxide ion. A . electrophilic substitution B .nucleophilic substitution C .electrophilic addition D .nucleophilic addition

This is the major reaction for carboxylic acid derivatives. There is initially a nucleophilic addition to the carbonyl carbon and then the originial substituent is displaced...eg, the hydrolyis of an ester by hydroxide ion. A .electrophilic substitution B .nucleophilic substitution C . electrophilic addition D .nucleophilic addition

This requires a polar solvent and a nonprotic is better so the nucleophile is not protonated. A .SN1 B .SN2 C .both D . neither

What is the C—N—H angle in CH3NHCH3? A .120 B . 109.5 C .100 D .90

What is the correct suffix for amide? A .-al B .-amide C .-oate D . correct suffix not listed

When salt, NaCl, is added into water, its boiling point (BP) A . decreases B . increases

Where is the absorption, given in wave numbers, of the saturated carbon hydrogen (C-C-H) which is intermediate and sharp A .2750-2850 B . 2850-2960 C .3020-3100 D .3300

Which is a true statement about Prostaglandins? A .sex hormones B . diverse biological functions C .cell membranes D .energy storage

Which is the approximate ppm (chemical shift or δ) from TMS in the H1 NMR for:unsaturated Alkane (unsaturated C=C-C—H) A . 0-1.5 B . 1.5-2.5 C . 0-5.0 D . 2.5-4.5

Which is the correct sequence of reactivity of carboxylic acid derivatives for nucleophilic substitution reactions? A . acid halide>anhydride>ester>amide B . anhydride>acid halide>ester>amide C . ester>amide>anhydride>acid halide D . amide>ester>anhydride>acid halide

Which of the following is NOT a basic amino acid? A . arginine B . serine C . histidine D . lysine

Which suffix is correct for CH3—CONHCH3? A .-al B . -amide C .-oate D .-oic acid

An Hydroxyl (non-hydrogen bonded) absorption in an IR spectrum is best described as A . broad B .sharp C .weak D .medium (strength)

B. 1750 cm-1; 2900-3000 cm-1; 3500 cm-1 broad and strong, 1100 cm-1 medium. The 1750 is the carbonyl group (C=O) absorption. The 2900 is the aliphatic (C-C-H) absorption, the 3500 is the hydroxyl group (OH) with hydrogen bonding, and the 1100 is the carbon-oxygen single bond (C-O). If there are no other key absorptions, this would be consistent with a carbonyl and probably an aliphatic carboxylic acid .

Which of the following results when a tertiary alcohol reacts with HBr? A .intermediate carbocation formed and alkene results B . intermediate carbocation formed and substitution of OH results C .no intermediate carbocation formed and alkene results D .no intermediate carbocation formed and substitution of OH results

B. A carbocation does result and the Br substitutes for the OH. The reaction is a Sn1 reaction.

Which of the following results when a tertiary alcohol reacts with HBr? A intermediate carbocation formed and alkene results B . intermediate carbocation formed and substitution of OH results C .no intermediate carbocation formed and alkene results D .no intermediate carbocation formed and substitution of OH results

B. A carbocation does result and the Br substitutes for the OH. The reaction is a Sn1 reaction.

When combined with a p-orbital, this orbital can help form a double bond. A .sp3 orbital B .sp2 orbital C .sp orbital D . all of these

B. A double bond is formed from a sigma and a pi bond. The sp2 orbitals form the sigma bond and the remaining p orbitals form the pi bond which results in a double bond.

Keto-enol tautomerization A .occurs only for ketones B . involves the intramolecular shift of a hydrogen C .results in the formation of a resonance hybrid D .may only exist as a transition state

B. A hydrogen shifts from the alpha carbon to the carbonyl oxygen. This converts the carbonyl carbon-alpha carbon bond to a double bond, and converts the carbonyl to an alcohol.

This type of molecule will have one hydrogen(s) bonded to the nitrogen. A .primary B .secondary C tertiary D . none of these

B. A secondary amine has only one hydrogen

The main reactions of alkanes are __________ and __________. A . elimination, nucleophilic B .combustion, radical C .substitution, electrophilic D .nucleophilic, electrophilic

B. Alkanes are chemically unreactive except in combustion and free-radical reactions. * Elimination reactions occur when a compound with a functional group such as hydroxy (alcohol) has the elimination of the OH and H (as water) and a double bond results. A nucleophilic reaction is when a nucleophile attacks a substrate which has a positive center. The substrate will need to have an electronegative functional group such as a carbonyl (ketone or aldehyde) for the nucleophile to attack the positive center. Since alkanes do not have any type of functional group, they will not undergo elimination nor nucleophilic reactions.

All non-aromatic rings may demonstrate A .Position isomerism B . Cis trans isomerism C .Chain isomerism D .Functional isomerism

B. All non-aromatic rings may demonstrate cis-trans isomerism depending on their structure. Aromatic rings would not demonstrate cis-trans isomerism

Increased torsional and steric strains result from this conformation of cyclohexanes. A .chair B . boat C .axial D .equatorial

B. This conformation increases both steric and torsional strains because of the orientations of the bonds.

For the ring form of glucose, the _________ anomer is more stable because _________________ A .beta, there is less ring strain B . beta, all substituents are equatorial C .alpha, there is less ring strain D .alpha, all substituents are equatorial

B. All of the substituents in the beta anomer are in the equatorial positions which makes it more stable than the alpha anomer which has the anomer substiutent in the axial position.

Which term best describes Amylose? A .ketose B . polysaccaride C .pentose D .hexose

B. Amylose is made of units of glucose and has alpha 1,4 and 1,6 bonds.

Each of the following is a correct description of a reduction EXCEPT A .a decrease in the oxidation state B . a decrease in the number of hydrogens C .occurs at the cathode D .a gain of electrons

B. An increase in the number of hydrogens is a measure of reduction in organic compounds.

Benzene is most likely to undergo which of the following reactions? A . nucleophilic substitution B .electrophilic substitution C .electrophilic addition D .electrophilic replacement

B. Aromatic rings undergo electrophilic substitution such that the aromaticity may be retained.

Which group of similar mass compounds will have the higher boiling points? A .alkane B . aromatic C .alkene D .all will be identical if the masses are equal

B. Aromatics will have the highest boiling points of these hydrocarbons. The conjugated systems produce some polarities not present in the alkanes or alkenes.

Which group of similar mass compounds will have the higher boiling points? A .alkane B .aromatic C . alkene D .all will be identical if the masses are equal

B. Aromatics will have the highest boiling points of these hydrocarbons. The conjugated systems produce some polarities not present in the alkanes or alkenes. A is incorrect because Alkanes will have the lowest boiling points as there are only dispersive forces acting.

When a solute is added to a pure liquid, the boiling point of the liquid solution will A . decrease B .increase C .remain the same D .cannot predict unless molalities are known

B. Boiling point is a colligative property. When solute is added, there is a boiling point elevation.

Which of these oxygen containing compounds will have the highest boiling points/melting usually? A .ketones B .carboxylic acids C .aldehydes D .alcohols

B. Carboxylic acid have extensive hydrogen bonding because of the carbonyl and hydroxyl component. They have more than alcohols and would have higher boiling points than alcohols.

In an NMR spectrum, hydrogens will be shifted more downfield if A . they are adjacent to alkyl groups B .they are near double bonds C .there is electron donation to them via sigma bonds D .all of the above

B. Double bonds result in an electron current which can oppose the applied field and cause the downfield shift. Double bonds are also electron withdrawing. Both of these can result in downfield shitts (away from the reference TMS).

A key difference between alkanes/aromatics and alkenes, is that the former will NOT react with bromine in the __________without a __________. A .dark, nucleophile B . dark, catalyst C .light, nucleophile D .light, heat source

B. Double bonds undergo several important reactions. One is an electrophilic addition of bromine (Br2) in the dark. This may be used to identify the presence of a double bond. An aromatic compound will not react with bromine in the dark. A regular alkane or aromatic will not react with bromine in the dark without a catalyst.

A Friedel-Crafts alkylation is A .the addition of alkyl group using an alkane and UV light to the aromatic ring B . the addition of an alkyl group to an aromatic ring using an alkyl halide and a Lewis Acid C .the addition of an alkyl group to an aromatic ring using an organometallic compound D .the addition of a halide to an aromatic ring using a halogen and UV light

B. In the Friedel-Crafts akylation, a R-Br, alkyl halide, reacts with an aromatic ring, AH, with use of a Lewis Acid, such as AlCl3. The product is A-R where the alkyl group, R, substitutes for the H on the AH in an electrophilic substitution reaction. The R-Br is activated by the AlCl3 as follows: AlCl3-Br----R+ where the R+ is now a stronger electrophile to attack the double bond of the aromatic ring.

At its pI, an amino acid or protein _________ migrate in a(n) ___________ field A .will not, magnetic B . will not, electric C .will, magnetic D .will, electric

B. Isoelectric points (IPs) exist for amino acids (AAs) and proteins. IPs are the pHs at which the AA or protein is neutral (has no net charge). This does not mean there are no charges on the molecules; it just means the charges sum to zero. At pHs below an IP, the AA will be positive (protonated on the amino group). At pHs above the IP, the AA will be deprotonated (the acid will lose its hydrogen). Acidic AAs will have lower IPs because of the extra carboxyl group. Basic AAs will have higher IPs because of the added basic groups. At the IP, the AA or protein will not migrate in an electric field. The pH of the IP is called the pI, and it is interpreted and used in the same way as the pH.

How does this molecule act in acid-base reactions? Φ—OH (ø=benzene ring) A .acts as a base only B .acts as a base and an acid C . acts as an acid only D .acts as neither an acid nor base

B. It can act as both an acid and a base. The oxygen has a free pair of electrons...these can be donated...This makes it a Lewis base. Additionally, it can accept a proton on the free pair of electrons...this makes it a Bronsted-Lowry base. The proton on the oxgyen may be donated...this makes it a Bronsted-Lowry acid.

he hybridization found in benzene which is responsible for its aromaticity is A .sp B . sp2 C .SP3 D .s orbitals

B. It is the sp2 hybrids and the p orbitals which account for the double bonds and allow for the aromaticity.

This (these) bond(s) have electron density above and/or below the plane of the nuclei. A .characteristic of sigma bonds B . characteristic of pi bonds C .characteristic of both sigma and pi bonds D .characteristic of neither sigma nor pi bonds

B. Only pi bonds have the electron density above and below the plane connecting the bonds.

An amino acid with this side chain, CH3CH2C(CH3)H—, would be found at/on the A . outside surface of protein B .inner regions of protein C .active site of acid catalysis D .active site of basic catalysis

B. This is a hydrocarbon and will be neutral and nonpolar. It will be found internally in proteins. This is a dichotomy of options question. Since there is no specific reference to enzymes, and since the molecule has no functional group which would normally participate in enzyme catalysis, it would be safe to eliminate options C/D and take a guess from A/B. This is isoleucine.

This is a slow process which will result in a nearly single solid coming out of the solution. A .precipitation B . recrystallization C .saturation D .solvation

B. Recrystallization is a technique for isolating a substance from a mixture. It is not an efficient process, and often significant amounts of the desired substance are lost in the process. Recrystallization is distinguished from precipitation in two ways. First, recrystallization is much slower than precipitation, occurring over hours to days versus seconds to minutes. Second, precipitation results in increased impurities being in the solid phase with the desired substance.

The no. of double bonds in a saturated fatty acid is A . 0 B .1 C .2 D .2 or more

B. Since the fatty acid is an "acid", meaning carboxylic acid, there is one double bond for the carbonyl carbon.

A strong broad band on an IR spectrum is seen at 3350cm-1. The absorption could represent a(n) A .ether B . alcohol C .ketone D .ester

B. The absorption at 3350 cm-1 will be for acetylenic hydrogen (but will be small), for N-H bonds, but will be moderate strength, but the O-H bond will be strong and will then be broad is hydrogen bonded.

A strong band on an IR spectrum is seen at 1750cm-1, the absorption could represent a(n) A alcohol B . carboxylic acid C .aromatic ring D .ether

B. The absorption noted is at the location a carbonyl group absorbs. A carboxylic acid has a carbonyl group...none of the other options do.

Acetaldehyde is converted into ethanol by the addition of ___________ which is a(n) ________________. A .H2, oxidation B . H2, reduction C .OH, oxidation D .OH, reduction

B. The aldehyde (>C=O) group of acetaldehyde is converted to the alcohol (OH) group when H2 is added. The reaction can be accomplished with catalytic hydrogen (Pd/H2, eg) or by NaBH4(sodium borohydride).

In the Hofman Elimination Reaction, a(n) _____________ is formed from an amine. A .Alkane B . Alkene C .Alkyne D .Ketone

B. The amine is converted to quaternary amine and Ag2O generates a base to remove a hydrogen from a carbon eliminating a tertiary amine. The least substituted alken is formed.

If the bonds of unsaturated fatty acids are cis, the molecule is A .Linear B . Nonlinear C .Chiral D .Any of the above are possible

B. The cis double bond causes the molecule to be kinked

A copper-lithium organometallic compound will react with a carbonyl compound at A .at any of the positions B .the alpha-beta unsaturated position C the alpha carbon D . the carbonyl carbon

B. The copper-lithium compound reacts at the beta position of the alpha-beta unsaturated carbonyl:

This orbital forms part of the double bond in carbon, oxygen and nitrogen. A .sp3 orbital B .sp2 orbital C .sp orbital D . all of these

B. The double bond is made from the left-over p orbitals (pi bond) and one of the sp2 orbitals (sigma bond). .

Unsaturated fatty acids as compared to saturated fatty acids have __________, tend to be __________ and have __________ melting points. A .double bonds, solids, higher B . double bonds, liquids, lower C. no double bonds, solids, higher D .no double bonds, liquids, lower

B. The double bonds decrease the mass of the fatty acid (decreasing its dispersive forces), and certain double bonds make it more difficult for the molecules to align and form solids. So, the melting points are lower and they tend to be liquid especially as the number of double bonds increase (polyunsaturated) and if the bonds are cis rather than trans (trans fatty acids or trans fats).

__________ may help hold proteins in the membrane in place A .microtubules B . microfilaments C .phospholipids D .cholesterol

B. The microfilaments provide structure and anchoring functions for the cell and cellular components.

Mass spectroscopy uses what property to identify molecules? A .Molecular vibrations B . Mass/charge C .Magnetic spins D .Electronic transitions

B. The molecules are broken into charged fragments, and the mass/charge ratio is determined by a magnetic field

The most important factor in the rate of an SN1 reaction is A .the strength of the nucleophile B .the stability of the carbocation C .the stability of the leaving group D . all are equally important

B. The most important is the carbocation stability, then the leaving group and the least is the strength of the nucleophile *The stability of the carbocation is a critical factor in the rate of SN1 reactions. As the stability of the intermediate carbocation increases, so does the rate of the reaction. In fact, SN1 reactions do not occur for primary and methyl groups. The stability of the leaving group is also important, but the strength of the nucleophile is not (because it is not part of the rate-limiting step).

Which is the electrophilic part of water? A .the oxygen B . the hydrogen C .the free electron pair on the hydrogen D .the free electron pair on the oxygen

B. The oxygen pulls electron density from the hydrogens making them partially positive...they would be seeking electrons...ie, electrophilic.

The pKa(TEA) of the salt of triethylamine as compared to the pKa(A) of the salt of aniline. A .pKa(TEA) is lower than pKa(A) B .pKa(TEA) is higher than pKa(A) C . pKa(TEA) is the same as the pKa(A) D .cannot be determined with the information given

B. The pKa(TEA) of the salt of triethylamine would be near that of trimethylamine which is higher than that of the pKa(A) of the salt of aniline. This could be deduced by arguing that aniline would be less basic than triethylamine because aryl groups would lower the basicity of nitrogen whereas alkyl groups would raise it. Then the pKa of salts of more basic amines is known to be higher than salts of less basic amines. Also, the relationship of pKbpKa=pKw may be used to predict the relative pKa's of the conjugate acids. The pKb is for the base (or amine) and the pKa is for its conjugate acid. The pkw is the ion product value of water, which is 14. Since the pKb of aniline is higher than the pkb of triethylamine (the weaker base has the higher pKb), this means the pka(A) has to be lower than the pKa(TEA).

Polar aprotic solvents enhance the reaction. A .SN1 B . SN2 C .both D .neither

B. These are better with aprotic solvents because they do not protonate the nucleophile which must be stronger. Polarity is important for the nucleophile and the leaving group.

Which is the best descriptor of an Epimer? A .the carbonyl carbon B . sugars which differ only at one carbon C .shows ring forms of sugars D .this is the optical isomer of glyceraldehyde which is basis of the most natural sugars

B. This can be at any of the asymmetric carbons. They would be diastereomers and not enantiomers.

The main bond between two glucoses in cellulose is called A .β-4,1 glycosidic bond B . β- 1,4 glycosidic bond C .β-1,5 glycosidic bond D .β-1,6 glycosidic bond

B. This is the acetal bond with the anomeric carbon and the 4th carbon of the glucose molecule

Higher torsional and steric strain are found in this conformation. A .staggered B . eclipsed C .gauche D .anti

B. This is the worst conformation for steric strain and torsional strain...both the substituents and bonds are aligned with each other.

At the melting point of a solid when the solid is melted, the energy supplied to the substance as heat is used to __________ and the temperature will __________. A . break most/all of the intermolecular forces, rise B .break some/many of the intermolecular forces, remain constant C .break all of the intermolecular forces, rise D .break no intermolecular forces, temperature will rise

B. This is what happens as phase go from solid to liquid to gas at the conversion temperatures (the melting point, the boiling point). When the conversion is from solid to liquid, many or most of the forces are broken but all are not. When the conversion is from liquid to gas, all of the intermolecular forces are broken.

Which molecule has the highest boiling point (BP)? A .CH3—CH3 B . CH3—CH2—Br C .CH2=CH2 D .CH≡CH

B. This molecule has Br which is electronegative compared to C and H. This means this compound is polar (since it is not symmetric). This means dipole-dipole type intermolecular forces are present. Since the other molecules shown are all hydrocarbons (only carbon and hydrogen), they will only have dispersive forces which are weaker than the dipole-dipole forces. The stronger the intermolecular forces, the higher the BP.

The main reaction of aromatic compounds is A .nucleophilic substitution B . electrophilic substitution C .electrophilic addition D .electrophilic replacement

B. This reaction occurs because the aromaticity is always conserved.

Each of the following is a correct description of an oxidation EXCEPT A .an increase in the oxidation state B . an increase in the number of hydrogens C .occurs at the anode D .a loss of electron

B. This would be a reduction

Which best describes a Wax? A .hydrolysis with an alkali base yields glycerol and soap(s) B .hydrolysis will yield one long chain fatty acid and one long chain alcohol C .contains no double bonds and is solid at room temperature D .made in units of isoprene

B. Waxes are composed of a fatty acid and a long chain alcholol-they are esters. So, when hydrolyzed, they are converted to a fatty acid (a salt if basic hydrolysis) and an alcohol.

Reducing agent A .accept electrons B . gives electrons C .None of the above D .Depends on the reaction

B. a reducing agent is oxidized...so, it has to give up its electrons.

This could be part of the overlap region of the C-X single bonds where X may be O, N etc may be found at this location, given in wave numbers, in an IR A .700 B .1100 C .1200 D . 1650

A Chemical shift is important in which type of spectroscopy? A .infrared spectroscopy B .mass spectroscopy C . NMR spectroscopy D .UV spectroscopy

A molecule is the non-superimposable non-mirror image optical isomer of another molecule, these molecules are A . enantiomers B . meso compound C . diastereomers D . geometric isomers

A molecule is the non-superimposable non-mirror image optical isomer of another molecule, these molecules are A .enantiomers B .meso compound C . diastereomers D .geometric isomers

A nucleophilic substitution reaction occurs when a nucleophile __________a leaving group and the carbon attacked is __________. A .eliminates, sp3 B .eliminates, sp2 C .replaces, sp3 D . replaces, sp2

A secondary amine reacts with a ketone/aldehyde to form a(n) A .imide B .amide C .enamine D . imine

All of the following would be expected in the IR spectrum of an aliphatic aldehyde EXCEPT A .a moderate band at 2900 to 3000 cm-1 B .a strong band at 1750 cm-1 C . a moderate band at 1100 cm-1 D .a small sharp band at 2850 cm-1

An aldehyde is A . CH3COCH3 B . CH3OCH3 C . CH3CHO D . CH3CONH2

CH3 — O—CH3:What is the suffix of the functional group of this molecule? A .-yne B . -ol C .ether D .-nitrile

CH3 — O—CH3:What is the suffix of the functional group of this molecule? A .-yne B .-ol C . ether D .-nitrile

CH3CH2 —SH:What is the suffix of the functional group of this molecule? A . -yne B . -ol C . -thiol D . -nitrile

Carboxylic acid derivatives differ from the carboxylic acid by differing by the substitution of other groups for A . one of the alpha hydrogen's B . both of the alpha hydrogen's C . the hydroxy group D . the carbonyl group

Contains the same number of each type of atom. A . structural (constitutional) isomer B . stereoisomer C . all of these D . enantiomer

During recrystallization A .any solvent which dissolves the substance is adequate B .the solvent should have a low vapor pressure C . the process should occur slowly rather than rapidly D .a large amount of the desired substance is usually isolated

Fatty acids are ___________ and soluble in ___________solvents. A . polar, non-polar B . polar, polar C . non-polar, non-polar D . non-polar, polar

If an acid, RCO2H, dissolves in a base, NaOH, in water solution, the products are A . RCO2H(aq) and OH- B . RCO2H(aq) and HOH C . RCO2-Na+ and HOH D . RCO2-Na+ and OH-

In a NMR spectrum, a hydrogen is shifted upfield if A . a double bond is placed next to it B . a clorine is placed on the carbon adjacent to it C . a methyl group is placed on the carbon next to it D . an aromatic group is placed on the carbon next to it.

In an E1 reaction, the slow step is A . the attack of the electrophile on the double bond B . the elimination of the leaving group to form the double bond C . the formation of the carbocation D . the attack of the nucleophile on the double bond

Nuclear spins are important in this spectroscopy. A .infrared spectroscopy B .mass spectroscopy C . NMR spectroscopy D .UV spectroscopy

P orbitals form A . Sigma bond B . Pi bond C . Both D . Neither

The IR absorption of an Alkene (C=C) is best described as A . broad B . sharp C . weak D . strong

The alpha beta unsaturated carbonyl is a(n) __________making the alpha, beta and carbonyl carbons all __________ hybridized. A . unconjugated system, sp2 B . unconjugated system, sp3 C . conjugated system, sp2 D . conjugated system, sp3

The ring form of a carbohydrate A .is the exclusive form of carbohydrates in solution B . will have one less asymmetric carbon than the open chain C .does not lose water when formed from the open chain D .will have the same conformations of the alpha and beta anomers

The spectroscopy used to determine the carbon-hydrogen skelton is A .Ultraviolet spectroscopy B .Infrared spectroscopy C . NMR spectroscopy D .Mass spectroscopy

There are multiple features which will make a group a better nucleophile. But, the one feature which must be present is A . a negative charge B . electron donating groups C . a free pair of electrons D . a group with low electronegativity

When a pure solid is melting, the melting point range will A . occur at one temperature point only B . occur at a temperature less than the triple point C . vary over a very narrow range D . vary over a broad rang

Where is the absorption, given in wave numbers, of the vinyl hydrogen (C=C-H) and aromatic hydrogens which are moderate and sharp. A .2750-2850 B . 2850-2960 C .3020-3100 D .3300

Which molecule would be the most reactive toward electrophillic addition? A . CH3—CH3 B . CH3—CH2—Br C . CH2=CH2 D . CH≡CH

A difference between recrystallization and precipitation is that recrystallization A .requires polar solvents B .results in more impurities C . is slower D .is used for solids

C. 1. Precipitation results in more impurities 2. Precipitation is a rapid process

Contains the same number of each type of atom. A .structural (constitutional) isomer B . stereoisomer C .all of these D .enantiomer

C. option A-This is a type of isomer and all isomers contain the same numbers and types of atoms. option B-This is a type of isomer and all isomers contain the same numbers and types of atoms. These have the same atoms attached to the same atoms. Option D-This is a type of optical isomer and stereoisomer. It is a non-superimposable mirror image.

Which is (are) the absorption(s), given in wave numbers, in the IR for a Nitro group? Assume all of the key absorptions are given. A .700-1300 cm-1 B . 1400-1650 cm-1 with multiple weak to strong peaks; 3000-3100 cm-1 C .1350-1540 cm-1 D .1650 cm-1 with single medium peaks; 3000-3100 cm-1

C. 1350-1540 cm-1. This is the range of a nitro group absorption. Usually two peaks and may be weak to strong.

A C—F group may have its absorption in an IR spectrum at this location (given in wave numbers). A .700 B . 1100 C .1200 D .1650

C. 1750 cm-1; 2900-3000 cm-1; 3500 cm-1 broad and strong, 1100 cm-1 medium. The 1750 is the carbonyl group (C=O) absorption. The 2900 is the aliphatic (C-C-H) absorption, the 3500 is the hydroxyl group (OH) with hydrogen bonding, and the 1100 is the carbon-oxygen single bond (C-O). If there are no other key absorptions, this would be consistent with a carbonyl and probably an aliphatic carboxylic acid . See the discussion of the correct option.

A non-superimposable, non-mirror image optical isomer. A .structural (constitutional) isomer B .stereoisomer C . diastereomer D .enantiomer

C. A diastereomer is a nonsuperimposable and nonmirror image optical isomer.

A racemate will have ___________ rotation of plane polarized light and ___________ physical properties as (from) the optical isomers composing it. A .non-zero degrees, different B .non-zero degrees, the same C .zero degrees, different D . zero degrees, the same

C. A racemate (racemate) is the equal concentrations of enantiomers. This results in zero rotation of plane polarized light as each enantiomer cancels the other. The physical properties of a racemate is distinct from the enantiomers composing it.

This type of molecule will have no hydrogens bonded to the nitrogen. A .primary B .secondary C tertiary D . none of these

C. A tertiary amine has no hydrogens

An alcohol would be most soluble in a(n) A .nonpolar solvent B .acid C . polar solvent D .base

C. Alcohols are polar and are capable of hydrogen bonding. So, they would be most soluble in these type of solvents. They are weakly acidic, so they may be soluble in certain acidic solvents/solutions, but this is less consistent than for polar solvents

An alcohol would be most soluble in a(n) A .nonpolar solvent B .acid C . polar solvent D. base

For the following molecule, H2Ca=Cb=CdH2 (allene or propadiene), what is the shape of this molecule? A .bent B . planar C .linear D .tetrahedral

C. Although, the geometry of a double bond is planar, the hybridization of the middle carbon is not sp2, as for the typical double bond. The middle carbon, b, has two double bonds. This means there are two pi bonds to it. The only way to get two pi bonds is if the atom is sp hybridized. This would make the three carbons linear. This molecule has the allene structure (consequtive double bonds to carbons). Note this is not a conjugated molecule which has alternating double bonds with the carbons, attached to double bonds, all sp2 hybridized.

The main reaction of an aliphatic double bond is A .electrophilic substitution B .nucleophilic substitution C . electrophilic addition D .nucleophilic addition

C. An electrophile first adds resulting in a carbocation and then the nucleophile adds to the carbocation

The main reaction of an aliphatic double bond is A . electrophilic substitution B .nucleophilic substitution C .electrophilic addition D .nucleophilic addition

C. An electrophile first adds resulting in a carbocation and then the nucleophile adds to the carbocation.

A secondary amine can function as all of the following EXCEPT A .Lewis Base B .Bronsted-Lowry Base C . Electrophile D .Nucleophile

C. An electrophile must seek out electrons or negative charges. This means an electrophile must be positive in some manner. A secondary amine has two carbon groups, one hydrogen and a free pair of electrons (R1R2HN:). This would make the molecule more negative than positive due to the electron pair... it will not function as an electrophile.

An aromatic compound in contrast to an equivalent number of conjugated double bonds will A .have a planar geometry for the double bonded carbons B .have a p orbital on each atom of the double bonded carbons C . undergo electrophilic substitution reactions D .undergo electrophilic addition reactions

C. Aromatics undergo electrophilic substitution reactions so that the aromatic ring may be reconstituted.

An amino acid with this side chain, Ø—CH2—(whereØ=benzene ring), would be best characterized as A .acidic B .basic C .neutral-non-polar D . neutral-polar

C. Correct. The group shown is a nonpolar aromatic hydrocarbon. Then, as an R group, it would result in a nonpolar amino acid. The amino acid shown is phenylalanine. There is no polar group in the side chain chain shown

Disulfide bonds are found in this level of protein structure: A .primary structure B .secondary structure C . tertiary structure D .quaternary structure

C. Disulfide bonds are occasionally important in holding the tertiary structure of some proteins.

A ring which is aromatic as opposed to a ring with double bonds which is NOT aromatic A .is less susceptible to nucleophilic attack B . is more susceptible to nucleophilic attack C .is less susceptible to electrophilic attack D .is more susceptible to electrophilic attack

C. Electrophilic attack occurs when an electropositive atom attacks the pi bond portion of the double bond. Because the pi component of the double bond is broken, this will disrupt the aromaticity of t.he ring (by converting one of the carbons from sp2 to sp3). This means the system is now less stable. An isolated double bond is more susceptible to electrophilic attack than an aromatic double bond.So, the aromatic system is less susceptible to electrophilic attack. B is incorrect because The aromatic ring has double bonds. These are electronegative and would attract positive and not negative atoms. Since a nucleophile would require a positive center to attack, this reaction type is very unlikely.

Requires the use of immiscible solvents. A .chromatography B .electrophoresis C . extraction D .fractional distillation

C. Extraction uses two immiscible solvents which allows the distribution of the solute between them after shaking. The solute is more soluble in one of the solvents. It usually requires multiple steps. The partition coefficient is the ratio of the solubility of the solute between the two solvents.

A large substituent is equatorial. A cis substituent on an adjacent carbon would be A .chair B .boat C .axial D . equatorial

C. In the chair conformation, adjacent carbons which have cis subtituents will alternate axial/equatorial bond types. So, if the large substituent is equatorial, which it should be, a cis substituent on an adjacent carbon has to be axial.

Mass spectroscopy can help in determining the A .functional groups of the molecule B .presence of double bonds which are usually conjugated C . mass of the molecule D .carbon structure of the molecule

C. Mass spectroscopy determines the mass of molecules.

The melting point of an organic compound will increase: A .as the intermolecular forces of the solid decreases B .as the molecular mass decreases C . as the Van der Waals forces in the solid increase D .as the polarity decreases

C. Melting point will increase as the van der Waals forces increase.

All are found in at least one of the naturally occuring amino acids EXCEPT A .two amine groups B a ring containing nitrogen C . a ring containing sulfur D .two carboxylic acid groups

C. No amino acid has a ring which has sulfur in it. There a number of amino acids with rings, and 3 with sulfur in the molecule.

A Nitrile signal may be found at this location, given in wave numbers, in an IR spectrum. A .700 B .1100 C . 2250 D .1650

C. On the IR spectrum between 2000 and 2500 cm-1, only the CΞC (alkyne or acetylenic) at 2150 cm-1 and the CΞN (cyano or nitrile) at 2250 cm-1 are generally found. These tend to be weak and sharp peaks

Which best describes a Saturated fatty acid? A .hydrolysis with an alkali base yields glycerol and soap(s) B .hydrolysis will yield glycerol, a nitrogen phosphate molecule, and a double bonded carboxylic acid among other components C . contains no double bonds and is solid at room temperature D .made in units of isoprene

C. Saturated fatty acids do not contain double bonds and tend to be solids at room temperature. Unsaturated fatty acids have one or more double bonds. The trans molecules tend to have higher melting points, are non-kinkedand may be solid/liquid. The cis molecules tend to have lower melting points, are kinked and are liquids at room temperature.

In a simple distillation apparatus, A .the column may be packed with glass beads B .substances of nearly equal boiling points will be separated C . the temperature at the top of the distilling column will be the boiling point of the most volatile substance D .the temperature at the top of the distilling column will be higher than the temperature at the bottom

C. Simple distillation is a one-step distillation process in which a mixture is heated to its boiling point, then allowed to vaporize and then condense in a separate flask. The setup includes a distilling flask for heating the mixture. A thermometer is present to measure the temperature changes. A condensation column is used to cool the vapor so condensation may occur- water usually flows through this column. A receiving flask is present to collect the distillate.

f the vapor pressure (VP) of a solution lowered, its boiling point (BP) will be A .unaffected B .decreased C . increased D. increase or decrease

C. The BP is the temperature at which the VP equals the external pressure (EP). If the VP is lowered, then more energy, and a higher temperature is needed, for the VP to equal the EP. Therefore, the BP will be elevated

Select the correct statement regarding the Fischer view A .represent ring carbohydrates B .the horizontal lines are bonds projected behind the paper C . the d series of sugars have the second last hydroxyl group to the right D .With this view, it is not possible to demonstrate enantiomers

C. The Fisher projections are straight chain forms of carbohydrates. When the hydroxyl group on the second to last carbon is to the right, this represents the D series. The L series, eg, for amino acids, would have the substituent (other than H) to the left.

Ultraviolet spectroscopy is used to identify A .the chemical formula B .the carbon structure C . the presence of double bonds D .functional groups

C. The UV will have peaks with double bonds and especially sensitive for conjugated bonds

Amines react with water to produce A .negative nitrogen ion B . ammonia C .hydroxide ions D .hydronium ions

C. The amine will hydrolyze water by abstracting one of the hydrogens with its free pair of electrons (a Bronsted Lowry base, or a Lewis bas). The hydroxide ion is then freed into solution to make it basic

Groups which __________ electrons from (to) the hydroxyl carbon of an alcohol will __________ the acidity of the hydroxyl H A .donate or withdraw, no effect on B . donate, enhance C .withdraw, enhance D .withdraw, weaken

C. The carbon attached the hydroxyl group will normally donates some electron density to the hydroxyl group. When groups are attached to the carbon, they can affect the acidity of the H on the O. Groups which donate electrons to the carbon will decrease the acidity of the H on the O. Groups which withdraw electron density will increase the acidity of the H on the O. This effect is twofold. First, the withdrawal of electron density from the O will decrease the strength of the O-H bond. Second, the negative charge which is left on the O when the H leaves, is stabilized by electron withdrawing groups on the carbon.

What are the hybridizations of carbons a and b and the oxygen in this compound? Dimethyl ether, CaH3OCbH3 A .a=sp3, O=sp2, b=sp3 B . a=sp3, O=sp, b=sp3 C .a=sp3, O=sp3, b=sp3 D .a=sp2, O=sp2, b=sp2

C. The carbons are fully saturated and are sp3. The oxygen has two bonds and two pairs of free electrons...this requires 4 hybrid orbitals which is sp3 as well.

Fatty acids are ___________ and soluble in ___________solvents. A .polar, non-polar B .polar, polar C . non-polar, non-polar D .non-polar, polar

C. The carboxylic acid group would make them polar and soluble in water, but the long carbon chains overpowers this and they are nonpolar. So, they will be soluble in nonpolar solvents.

Carboxylic acids have__________boiling points than alcohols because of more extensive __________. A .lower, polar bonds B .lower, hydrogen bonding C . higher, hydrogen bonding D .higher, polar bonds

C. The carboxylic acid has hydrogen bonding and polar bonding, but it is the hydrogen bonding which results in the higher boiling points. The hydrogen bonding in carboxylic acids is more extensive than that in the alcohols.

At the cathode of a galvanic cell A .oxidation occurs B .the electrode cannot participate in the reaction C . electrons move out of the electrode D .the electrode is negative

C. The cathode is where reduction occurs, so electrons must move from it to the substance being reduced

Match the average chemical shift in the C13 NMR for the group: C=O (carbonyl) A .90 ppm B . 130 ppm C .190 ppm D .210 ppm

C. The combination of the electronegativity of oxygen and the currents set up in the double bond causes a large shift of the signal downfield.

Match the average chemical shift in the C13 NMR for the group: C=O (carbonyl) A .90 ppm B .130 ppm C .190 ppm D . 210 ppm

C. The combination of the electronegativity of oxygen and the currents set up in the double bond causes a large shift of the signal downfield.

A hemiacetal is formed from a(n) __________ and _____________ A carboxylic acid and one alcohol B .carboxylic acid and two alcohols C . ketone or aldehyde and one alcohol D .ketone or aldehyde and two alcohols

C. The hemiacetal is formed from a ketone/aldehyde and an alcohol.

If a compound has an aldehyde group, an aromatic ring, a double bond and a methyl group. The one found closest to the TMS (in NMR) is the A .aldehyde group B . aromatic ring C .methyl D .double bond

C. The methyl group, which has the least electron withdrawal and not electron currents, will be the closest to the TMS.

The fused 10 membered ring composed of two fused cyclohexane rings is called __________and the __________form is more stable. A .cyclodecane, trans B .cyclodecane, cis C .decalin, trans D . decalin, cis

C. The simplest six-membered ring bicyclic is decalin, which serves as a model for more complex six-membered polycyclics (which may be made up of any number of different size rings). The decalins (all carbon and hydrogen) are composed of two six membered rings fused along one bond. The carbons at the points of fusion are called the bridgehead carbons, and it is the hydrogens at these carbons that determine the cis-trans nature of the compounds. The two compounds are stereoisomers of each other. The trans form would be more stable than the cis form because the substituents, especially if larger than H, are farther from each other. The two compounds are fixed in the configurations shown and do not equilibrate from one form to another. The chair forms are present.

The boat form of cyclohexane is destabilized by I-Ring Strain II-Steric Strain III-Torsional Strain A .I only B .I and II only C .II and III only D . I, II and III

C. The six-membered ring has no ring string in either boat or chair conformations. There is steric strain caused by the 1,4 substituent interactions. Also, torsional strain is caused by the interactions of substituent bonds at 2,3 and 5,6 (assume 1 and 4 are the bow and stern of the boat)

The boat form of cyclohexane is destabilized by I-Ring Strain II-Steric Strain III-Torsional Strain A .I only B .I and II only C . II and III only D .I, II and III

The pKa(EA) of the ammonium salt of Ethylamine as compared to the pKa(MA) of the ammonium salt of Methylamine: A . pKa(EA) is lower than pKa(MA) B .pKa(EA) is higher than pKa(MA) C .pKa(EA) is about the same as pKa(MA) D .cannot determine relationship from information given

C. There is little difference in the basicity of the alkyl amines, so little difference would be expected in the pKa of their ammonium salts. The ammonium salt is the conjugate acid of the amine itself. To get the conjugate acid, a proton must be added to the amine. The higher the pKa of the conjugate acid of the amine, the stronger the amine as a base and the weaker the conjugate acid as an acid.

Which term best describes Lactose? A .ketose B .aldose C . β-1,4 glycosidic bonds D .pentose

C. This is a type of glycosidic bond. It is between the6 carbon of one sugar and the first of another (which is usually the anomeric carbon of an aldose). It is found in cellulose.

What is the suffix of the functional group of this molecule? CH3—COCl A .-al B .-amide C . correct suffix not listed D .-oic acid

C. This is an acid chloride. The suffix of an acid halide is -oyl halide...it is not listed

This ring has a puckered conformation. A . cyclopropane ring B .cyclobutane ring C .cyclopentane ring D .cyclohexane ring

C. This is puckered with one of the carbons out of the plane of the other four. This not only decreases ring strain slightly but also can decrease steric interactions and torsional interactions.

Extraction, as applied in organic chemistry, means removing a substance from a mixture by A .boiling B .manually picking its crystals from the mixture C . allowing it to equilibrate between two immiscible liquids D .applying electric fields to it

C. This is the extraction process. The substance will move to the liquid/solvent in which it is most soluble

Where is the absorption, given in wave numbers, of the Vinyl hydrogen (C=C-H)? A .2750-2850 B .2850-2960 C . 3020-3100 D .3300

C. This is the range of the vinyl hydrogen (C=C-H) and the aromatic hydrogens' absorptions.

Which is the correct suffix for this molecule: CH3CH2-CO2CH3? A .-al B .-amide C . -oate D .-oic acid

C. This is the suffix for an ester which this molecule is.

CH3CH2 —SH:What is the suffix of the functional group of this molecule? A .-yne B .-ol C . -thiol D .-nitrile

C. This is the thiol which is the oxygen counterpart of the alcohol group. It is also called a mercaptan

An aliphatic double bond may be formed by A .halohydrogenation B . bromination C .dehydration D .nucleophilic substitution

C. This would be the removal of water (an H on one carbon and an OH on an adjacent carbon). The single bonded is carbon is converted to a double bonded carbon. Dehydrogenation would be the removal of two hydrogens.

In a NMR spectrum, a hydrogen is shifted upfield if A .a double bond is placed next to it B .a clorine is placed on the carbon adjacent to it C . a methyl group is placed on the carbon next to it D .an aromatic group is placed on the carbon next to it.

C. Upfield is toward the 0 delta or TMS reference...the greater the electron density, lack of electron withdrawing groups, and lack of circulating electrons (as in double bonds or aromatics) result in upfield shifts. Downfield is away from the TMS reference point...just the reverse of the above results in movement downfield. An alkyl group has increased electron density and would result in upfield movement of the location of the hydrogen signal.

An anomer is A . when two epimers exist in one monosaccharide B .the bond formed between two monosaccharides C .the chiral center formed when straight chains are converted to ring forms D .structural isomers

C. When the straight-chain form of a carbohydrate is converted to the ring-form, a new chiral center is formed which called the anomer carbon or anomer.

Which is the best description of an Alkyne IR spectrum absorption? A .broad B .none of these C .weak D . strong

C. he absorption is at about 2150 cm-1 and is weak and sharp similar to the nitrile (cyano) aborption at about 2250 cm-1.

Carbohydrates are found in all of the following EXCEPT A . bound to lipids B .cartilage C .bony matrix D .chitin

C. he bony matrix contains calcium, phosphate and proteins.Carbohydrates serve as the main short-term energy source, having 4.1 kcals/g. There are very small amounts of carbohydrates stored as glycogen in the liver and muscles. Carbohydrates also function as structural components (e.g., in cartilage, chitin, and membranes) and are bound to proteins (as glycoproteins) and lipids (as glycolipids).

The key reason for the general rule of 'like dissolves like' for solubility is A .volatility B .acid-base properties C . intermolecular forces D .covalent forces

C. like dissolves like" is based on the similarity of intermolecular forces between molecules. Different molecules with similar intermolecular forces tend to dissolve in each other. Those with different intermolecular forces tend to be less soluble or insoluble in each other. E.g., substances with only dispersive forces will tend to be soluble in each other. But, one substance with only dispersive forces and another with primarily dipole forces will be insoluble in each other.

When an electrophile attacks a double bond, a __________ usually results. A .cannot determine B .radical C . carbocation D .carbanion

C. the pi bond attacks the positive charge and this results in a positive charge on the carbon-a carbocation

The pinacol rearrangement takes a __________ compound and converts it to a __________via an acid catalyzed reaction involving a rearrangement. A .mono-alcohol, ketone B .mono-alcohol, aldehyde C . 1,2 dihydroxy, ketone D .1,2 dihydroxy, aldehyde

C. the reaction begins with a 1,2-hydroxy compound and rearranges it to a ketone: The steps are: The acid protonates one of the hydroxyl groups, making it positive, and this is now a good leaving group; it leaves, leaving the Pinacol carbocation on the Cb carbon.The Pinacol carbocation (at Cb) is stable but a shift is still possible for a methyl group (from Ca) to the carbocation. This results in Ca , with the positive charge now on the carbon with the remaining hydroxyl group; this is a very stable carbocation because of the resonance stabilization of the free electron pairs on the oxygen. The hydrogen of the OH, on Ca, leaves and the ketone group, on Ca, of the Pinacolone (if all the R's are methyls) is formed. This reaction may occur with any similar arrangement of hydroxyl groups.

The strongest intermolecular forces are A .covalent bonds B .dipole forces C . hydrogen bonds D .van der Waals forces

C. these are strongest and can only occur with N, F and O

All of the following would be expected in the IR spectrum of an aliphatic carboxylic acid EXCEPT A .a moderate band at 2900 to 3000cm-1 B .a strong wide band at 3300 to 3600cm-1 C .a moderate band at 3000 to 3100cm-1 D . a moderate band at 1100cm-1

C. this would be for aromatic hydrogens

This type of molecule will have some minimal ring strain and has torsional and steric strain. A .cyclopropane ring B . cyclobutane ring C .cyclopentane ring D .cyclohexane ring

C.There is minimal ring strain due to the puckered conformation. This decreases but does not eliminate all of the torsional or steric strain.

name the functional group R - COOH one O is double bonded (carbonyl) other O is as hydroxyl (OH)

Carboxylic Acid (-oic acid)

whats the difference between configurational isomers and conformational isomers

Configurational isomers cannot be converted into each other at room temperature. Conformational isomers can be converted into each other by rotation about a single bond at room temperature.

whats a constitutional isomer

Constitutional isomer (also called structural isomers) isomers differ by having different carbon structures or different functional groups

This is the major reaction of carbonyls (ketones or aldehydes). A nucleophile adds to the carbonyl carbon to form the tetrahydral addition product. A .electrophilic substitution B .nucleophilic substitution C . electrophilic addition D .nucleophilic addition

If two hydrogens are next to a methyl group, the NMR signal of the two hydrogens will have __________peaks. A .1 B .2 C . 3 D .4

when in a fisher projection as shown if the hydroxyl group on the highest numbered chiral carbon points to the right then it is labeled as (D/L) and if to the left then it is labeled (D/L)

D, L

A Carbonyl signal may be found at this location, given in wave numbers, in an IR spectrum. A . 700 B . 1100 C . 1200 D . 1750

A Carbonyl signal may be found at this location, given in wave numbers, in an IR spectrum. A .700 B .1100 C .1200 D .1750

A basic amino acid is A . phenyl alanine B . glycine C . valine D . lysine

A mixture of compounds which have physical properties, other than rotation of polarized light, the same as its component compounds. A . structural (constitutional) isomer B . stereoisomer C . optical isomer D . none of the above

An Alkene (C=C) signal may be found at this location, given in wave numbers, in an IR spectrum. A .700 B .1100 C .1200 D . 1650

An acetal is formed from a(n) __________ and _____________ A .carboxylic acid and one alcohol B .carboxylic acid and two alcohols C . ketone or aldehyde and one alcohol D .ketone or aldehyde and two alcohols

An example of a basic amino acid is A . aspartic acid B . serine C . cysteine D . lysine

An identifying Amine signal may found at this location, given in wave numbers, in an IR spectrum. A .700 B .1100 C .1200 D . none of these

At the pI of an amino acid A . the amino acid will migrate in an external electric field B . the carboxyl group is neutral C . the amino group is negatively charged D . the amino acid is charged but neutral

C10:What is the prefix of this carbon chain grouping? A .non- B .prop- C .hex- D . dec-

CH3COOCH2CH3:What is the suffix of the functional group of this molecule? A .-yne B .-ol C .ether D . -oate

Fats are digested mainly by enzymes from the A .stomach B .gallbladder C .liver D . pancreas

For the following molecule, H2Ca=Cb=CdH2 (allene or propadiene), what is the correct hybridization of each carbon? A . a=sp, b=sp2, c=sp B . a=sp, b=sp, c=sp C . a=sp2, b=sp2, c=sp2 D . a=sp2, b=sp, c=sp2

Mixed products will result in the aldol condensation EXCEPT when A . the carbonyl reacts with itself B . one carbonyl has no alpha hydrogen's C . one carbonyl has the alpha hydrogen's much more acidic than the other D . all of the above will result in limited products

NMR spectroscopy can help in determining the A .functional groups of the molecule B .presence of double bonds which are usually conjugated C .mass of the molecule D . carbon structure of the molecule

Organocopper compounds are formed from ____________ and _____________ A . two alkyl halides, one cuprous(I) iodide B . two alkyl lithium halides, one copper metal C . one alkyl halide, one copper metal D . two alkyl lithium halides, one cuprous(I) iodide

Tautomerization A .is a resonance hybrid resulting in a shift of a hydrogen from the carbonyl to the alpha carbon B .is a resonance hybrid resulting in a shift of a hydrogen from the alpha carbon to the carbonyl carbon C .is an equilibrium resulting in a shift of a hydrogen from the carbonyl to the alpha carbon D . is an equilibrium resulting in the shift of the alpha hydrogen to the carbonyl oxygen

This hybrid orbital can form one or more sigma bonds. A .sp3 orbital B .sp 2 orbital C .sp orbital D . all of the above

This is the major reaction of carbonyls (ketones or aldehydes). A nucleophile adds to the carbonyl carbon to form the tetrahydral addition product. A . electrophilic substitution B .nucleophilic substitution C .electrophilic addition D .nucleophilic addition

This ring assumes a chair conformation as its most favored conformation. A .cyclopropane ring B .cyclobutane ring C .cyclopentane ring D . cyclohexane ring

This spectroscopy may provide the molecular formula and molecular mass. A .infrared spectroscopy B . mass spectroscopy C .NMR spectroscopy D .none of these

This technique rarely results in complete separations of components of mixture. A .chromatography B .electrophoresis C .precipitation D . recrystallization

This type of double bond nomenclature is approprate for a double bond containing two hydrogens on one carbon and two different alkyl groups on the other carbon. A .cis-trans nomenclature B .Z-E nomenclature C .either of these D . neither of these

This type of molecule may be used to separate enantiomers in a racemic mixture. A . primary B . secondary C . tertiary D . quaternary

This type of spectroscopy provides the nearly complete molecular structure of a molecule. A . infrared spectroscopy B . mass spectroscopy C . NMR spectroscopy D . none of these

Viscosities at 20°C (N s/m2) Acetone 0.00032 Carbon Tetrachloride 0.00097 Ethanol 0.00120 Glycerol 1.49 Mercury 0.00155 Water 0.00101 Glycerol has three carbon atoms. Which is a possible structure of glycerol based on its viscosity (all are legitimate structures)? A . CH3—CH2—CH3 B . CH3—CO—CH3 C . CH3—O—CH2—CH3 D . HOCH2—CHOH—CH2OH

What is the correct hybridization for a, b and d carbons in this compound? 2-Methylpropene, (CaH3)2Cb=CdH2 A .a-sp3, b-sp, d-sp2 B .a-sp2, b-sp, d-sp2 C .a-sp3, b-sp, d-sp3 D .a-sp3, b-sp2, d-sp2

Which is (are) the absorptions, given in wave numbers, for an Alkyne group? Assume all of the pertinent absorptions are given. A .700-1300 cm-1 B . 1000-1200 cm-1; 3400-3500 cm-1 C .1650 cm-1 with single medium peaks; 3000-3100 cm-1 D .2150 cm-1; 3300 cm-1

Which is true about a Terpene? A . hydrolysis with an alkali base yields glycerol and soap(s) B . hydrolysis will yield one long chain fatty acid and one long chain alcohol C . contains no double bonds and is solid at room temperature D . made in units of isoprene

Which molecule contains the most acidic hydrogen? A . CH3—CH3 B . CH3—CH2—Br C . CH2=CH2 D . CH≡CH

Which of these is a steroid? I-progesterone II-testosterone III-cholesterol IV-Vitamin D A .III only B .I and II only C .I, II and III only D . I, II, III and IV

Which ring(s) has no ring strain? A .cyclopropane ring B .cyclobutane ring C. cyclopentane ring D . cyclohexane ring

Which of the following does NOT convert the hydroxyl group of alcohol to a better leaving group? A .acids B .SOCl2 C .PBr3 D . all of the above convert the OH to a better leaving group

D. a is correct An acid, which is stronger than the alcoholic group, will convert the -OH to -OH2+ which is an excellent leaving group. b is correct Sulfonyl chloride, SOCl2, will react with the -O-H to form -O-SOCl which is a very good leaving group. c is correct Phosphorus tribromide, PBr3, will react with the -O-H to form -O-PBr2 which is very good leaving group.

Which is (are) the IR absorptions, given in wave numbers, for a Nitrile? Assume all key absorptions are given. A .700-1300 cm-1 B .1000-1200 cm-1; 3400-3500 cm-1 C .1350-1540 cm-1 D . 2150 cm-1; 3300 cm-1

D. 2150 cm-1; 3300 cm-1. The 2150 peak would be the CºC bond, and the 3300 peak would be CºC-H (hydrogen) bond absorption.

This type of molecule will have four hydrogens bonded to the nitrogen. A .primary B .secondary C tertiary D . none of these

D. Correct. When there are four hydrogens attached to the nitrogen, this is the ammonium ion. This is a three out of four options question. Options A,B and C are all similar and D is the outlier. Generally, outliers will be incorrect...but, not always...a guess is a guess.

Conjugated double bonds are when __________and are __________stable than isolated double bonds. A .double bonds alternate with a single bond, less B .double and triple bonds alternate, more C . double bonds are back to back, less D .double bonds alternate with a single bond, more

D. A conjugated double bond is when two or more double bonds are in sequence, separated by a single bond. The conjugated double bond is more stable than isolated double bonds (those separated by two or more single bonds). The conjugated double bonds may be with other carbon-carbon double bonds, carbon oxygen double bonds or occasionally with carbon nitrogen double bonds. When conjugated double bonds have the opportunity to form, they will be preferred over isolated double bonds. Conjugated double bonds have lower energies for electronic transitions and will appear in UV spectra. The colored compounds of organic chemistry often have multiple conjugated double bond systems which allow electronic transitions to occur in the visible region.

The non-mirror image of an enantiomer. A .structural (constitutional) isomer B .stereoisomer C .optical isomer D . diastereomer

D. A diasteromer would be an optical isomer which is not a mirror image.

Which term best describes Maltose? A .ketose B .aldose C .pentose D . disaccharide

D. A disaccharide is composed of two monosaccharides bonded with a glycosidic bond (acetal formed).

Which terms is a description of Glucose? A .ketose B .pentose C .polysaccharide D . hexose

D. A hexose is a six carbon sugar. Glucose is six carbon sugar.

The best solvent for recrystallization will A .have the desired substance be highly soluble at low temperatures B .have impurities soluble at high temperatures C .have a boiling point higher than the melting point of the substance to be isolated D .have a high vapor pressure

D. A high vapor pressure, easy to evaporate, will allow the separation from the desired substance when cooled.

Which is the best description of a Ketose? A .the carbonyl carbon B .a ring form of sugars C .optical isomer of glyceraldehyde which is basis of the most natural sugars D . contains a ketone group

D. A ketose is when the carbonyl is a ketone on a sugar.

Which type of compound has the INCORRECT group associated with it? A .Acid halide-RCOX B .Acid anhydride-RCO2COR' C .Imide-RCONHCOR' D . Nitrile-RC=NH

D. A nitrile has a triple bonded C and N and would be RCΞN.

Reduction will A .show a gain of oxygen B .show a loss of hydrogen C .increase the oxidation number D . decrease the oxidation number

D. A, B, and C all happen in oxidation

Electrophoresis is used to identify and separate A .Amino acids B .Proteins C .Nucleic acids D . All of the above

D. All of these will have charges which are pH dependent. So, in an electric field, like in electrophoresis, they will differentially migrate.

Under vigorous conditions with alkenes which have a secondary carbon, permanganate and dichromate will form a(n) __________. A .aldehyde B .diol C .carboxylic acid D . ketone

D. Another important reaction is the oxidation of the double bond with KMnO4 (potassium permanganate) or K2Cr2O7 (potassium dichromate). If the carbon is a secondary carbon, a ketone will result. If the carbon is primary, a carboxylic acid will result. The conditions are vigorous. The permanganate solution is purple and this will be decolorized by the reacting double bond. KMnO4 (potassium permanganate) under mild (cold) conditions will also decolorize and lose its purple color as it adds to the double bond in an oxidation reaction, resulting in a diol (OH groups on adjacent carbons). OsO4 will also result in diols. Ozonolysis (O3) is an important oxidation of double bonds. This reaction can localize the double bond. Each carbon of the double bond will end up as a carbonyl, either a ketone or aldehyde. The original double bonded carbon was between these two carbons.

The base strength of amines decreases as ____________________ attached to the nitrogen. A .alkyl groups replace electron withdrawing groups B . the number of hydrogens replaces electron withdrawing groups C .aliphatic groups replace aromatic groups D .aromatic groups replace aliphatic groups

D. Aromatic groups are electron withdrawing and will make the amine less basic. Any group which withdraws more electrons will make the amine more basic.

All of the following are features of the Huckel Rule EXCEPT: A .molecule is planar B .atoms must be cyclic C .the number of pi electrons must be 4n+2 (n=0,1,2...) D . must be s orbitals on each atom

D. Aromaticity is the reason for the stability of the benzene ring and similar compounds. The Huckel rule gives a method of determining if a molecule is aromatic or not. The key features of the Huckel rule to determine if a compound is aromatic are: 1. The molecule is planar. 2. The molecule is cyclic. 3. Each atom of the cyclic structure has a p orbital. 4. The number of electrons in the ring must be 4n + 2, where n = 0, 1, 2, 3, ... , and is the number of electrons in the "p" orbitals. The rule is explicitly for single-ring compounds, but it is also applied effectively to multiple-ring compounds. There is no specific requirement for s orbitals.

Which structural feature is associated with the INCORRECT loss of hydrogen per feature in a compound? A .ring, lose 2 hydrogens B . oxygen, lose no hydrogens C .triple bond, lose 4 hydrogens D .nitrogen, lose 1 hydrogen

D. Because the N will normal have 3 bonds, in the uncharged state, there will be an extra hydrogen expected in compound with nitrogen.

Rotates plane polarized light. A .structural (constitutional) isomer B .stereoisomer C .meso compound D . enantiomer

D. Being an optical isomer, it will rotate plane polarized light

A ketone will have a higher boiling point (BP) than each of the following corresponding molecules EXCEPT A alkenes B .ethers C .alkyl halides D . carboxylic acids

D. Carboxylic acids are both polar and can participate in hydrogen bonding. This would make their BPs higher than ketones.

Conjugated double bonds are more likely to absorb in the __________ region than isolated double bonds. A .infrared B .microwave C .gamma ray D . ultraviolet

D. Conjugated double bonds have lower energies for electronic transitions and will appear in UV spectra. The colored compounds of organic chemistry often have multiple conjugated double bond systems which allow electronic transitions to occur in the visible region.

A double bond, added to a compound which had only carbons and hydrogens, will have this effect on the number of hydrogens in the compound: A .no effect B decreases H's by one C .increase H's by four D . decreases H's by two

D. Double bonds and rings will decrease the number of hydrogen by two for each one present.

Racemates are made of these. A .structural (constitutional) isomer B .stereoisomer C .optical isomer D . enantiomer

D. Enantiomers are mirror images. When both are present in equal amounts, a racemate results.

This type of molecule may be used to separate enantiomers in a racemic mixture. A .primary B .secondary C . tertiary D .quaternary

D. Enantiomers are separated by reacting them with another chiral compound. Eg., the enantiomers would be + and - with the same physical and chemical properties. But, it each reacted with a + quaternary amine, then the compounds would be +/+ and -/+ and each of these compounds would be different physically and chemically and separable.

Epimers A .differ at the carbonyl carbon B .differ at the second to last carbon C .have no hydroxyl group at one of the carbons D .different at any one of the chiral carbons

D. Epimers, for carbohydrates, will differ in orientation at one of the chiral carbons of the carbohydrate. They are diasteromers of each other. The carbonyl carbon is the anomeric carbon. In the ring form, this will become chiral and there will be two isomers possible at this position.

Which compound would be most soluble in toluene (a nonpolar solvent). A .RCOOH B .R-OH C .RCOOOCR' D . R-O-R'

D. Even though this has an oxygen, it is an ether, and ethers tend to be nonpolar. So, it would be more likely to be soluble in toluene. (like dissolves like)

Which is true for a Fatty acid? A . hydrolysis with an alkali base yields glycerol and soap(s) B .hydrolysis will yield one long chain fatty acid and one long chain alcohol C .contains no double bonds and is solid at room temperature D .unbranched with an even number of carbons

D. Fatty acids are unbranched, have an even number of carbons, reflecting their synthesis from Acetyl CoA, and are carboxylic acids. Saturated ones have no double bonds and are solid at room temperature. Unsaturated ones have one or more double bonds in the trans (linear or unkinked) with lower melting points than saturated, and the cis(kinked configuration) with the lowest melting points and are usually liquid at room temperature.

Which is true for a Fatty acid? A .hydrolysis with an alkali base yields glycerol and soap(s) B . hydrolysis will yield one long chain fatty acid and one long chain alcohol C .contains no double bonds and is solid at room temperature D .unbranched with an even number of carbons

Which is true regarding a Fischer projection? A .the carbonyl carbon is shown as a single bond B .shows ring forms of sugars C .it uses the optical isomer of glyceraldehyde which is basis of the most natural sugars D . shows straight chain configurations of sugars

D. Glyceraldehyde exists as an l- and d- isomers. This is based on the second carbon which is chiral. The d-enantiomer is the isomer on which the carbohydrates are based

This technique rarely results in complete separations of components of mixture. A . chromatography B .electrophoresis C .precipitation D .recrystallization

D. In this process, the solution is heated. Hopefully, the contaminants remain soluble and are removed. Then the solution is allowed to cool slowly allowing crystals to form and are then filtered off.

Which of the following requires more than carbon dioxide and water as elimination products? A . fatty acids B .glucose C .steroids D .proteins

D. Nitrogen elimination is a major problem for all animals. Nitrogen is found in proteins. Besides the carbon dioxide and water, the nitrogen also needs to be eliminated.

In all chromatography, the __________ polar substance moves along/through the chromatography medium __________ A .most, never moves B .most, the fastest C .least, the slowest D . least, the fastest

D. Nonpolar substances are not held by the medium of the chromatography unit. There are no bonds, either intermolecular types (hydrogen, dipole or significant dispersive) or ionic bonds formed. So, the nonpolar, least polar, will move through the medium very rapidly.

In the nucleophilic addition reaction to carbonyls A .the carbonyl adds to the carbonyl carbon B .the substituent attached to the carbonyl carbon may be an hydroxyl group C .the nucleophile adds to the alpha carbon D . the nucleophile adds to the carbonyl group

D. Nucleophilic addition is when a nucleophile attaches to the carbonyl carbon:

Alkanes tend to have ________ boiling points and _______ vapor pressures because of the ____________ forces present. A .low, high, dipole B .high, low, dipole C . high, low, dispersive D .low, high, dispersive

D. Once the vapor pressure (VP) of a liquid reaches the external atmospheric pressure, it will begin to boil. The temperature at this point is called the boiling point (BP) of the liquid. The BP is a colligative property. The heat released when the liquid is converted to the gas at the boiling point is called the heat of vaporization. VP is a function of the intermolecular forces between the liquid molecules. The stronger the intermolecular forces, the smaller the vapor pressure and the higher the temperature must be for the liquid to boil. The strongest intermolecular forces are the hydrogen bonds, next are the dipole forces, and weakest are the dispersive forces, also called van der Waal forces. The BP is defined as the temperature at which the VP of the solution (or liquid) equals the atmospheric pressure. If the VP of the solution is lowered, the BP is elevated. As more particles go into solution, the higher the BP of the solution becomes. Alkanes have no functional groups. They are nonpolar or hydrophobic ("water hating"). The boiling points are low and increase with increasing molecular mass because of dispersive forces. The vapor pressures tend to be high as well.This means alkanes will have lower boiling points, higher vapor pressures due to the presence of dispersive forces

A plane of symmetry is critical in this type of isomer. A .structural (constitutional) isomer B .stereoisomer C .optical isomer D . meso compound

D. The only requirement for an optical isomer is to have a chiral carbon Meso compounds are optical isomers which have a plane of symmetry.

Organometallic compounds are a convenient way to add a(n)__________to carbons which have a partial __________charge. A metallic ion, negative B .alkyl group, negative C .metallic ion, positive D . alkyl group, positive

D. Organometallic compounds will add an alkyl group, as a nucleophile, to a carbon which is partially positively charged. *Organometallic compounds act like nucleophiles as the alkyl portion has a pair of electrons, and has relative negative charge. These compounds act like carbanions, resulting in nucleophilic attack on positive (electrophilic) atoms. The net effect is add an alkyl group to an electropositive carbon.

Which of the following results when Phenol reacts with PBr3? A .intermediate carbocation formed and alkene results B . intermediate carbocation formed and substitution of OH results C .no intermediate carbocation formed and alkene results D .none of these

D. Phenols would not react with PBr3. Aliphatic alcohols react. Also, a phenol is aromatic and fully unsaturated. The reaction it undergoes is an electrophilic substitution. This would be a three out of four and this option would have been the one to eliminate usually...sometimes, you just have to know the answer.

Each of the following is a characteristic of recrystallization and NOT precipitation EXCEPT A .allowing formation of crystals B .having minimal to no impurities C .product exhibits a narrow melting point range D . occurring rapidly

D. Precipitation is a rapid process resulting in clumps and not sharply formed or pure crystals.

Precipitation is NOT a substitute for this process. A .chromatography B .electrophoresis C .extraction D . recrystallization

D. Precipitation is not a separation technique. This is when any solute leaves solution rapidly and forms a solid phase. In recrystallization, the solution is heated. Hopefully, the contaminants remain soluble and are removed. Then the solution is allowed to cool slowly allowing crystals to form and are then filtered off

Peptide hormones are mostly likely to act at__________ whereas steroid hormones are mostly likely to act at __________. A .the site of release, a distant site B .a distant site, the site of release C .the nucleus, at plasma membrane receptors D . at plasma membrane receptors, the nucleus

D. Proteins cannot cross membranes without help, steroids generally cross membranes easily

Which compound can have NO double bonded oxygens? A .molecule with 2 oxygens, 10 carbons and 20 hydrogens B .molecule with one oxygen, 3 carbons and 6 hydrogens C . molecule with one oxygen, one ring, 5 carbons and 8 hydrogens D .molecule with two oxygens, 6 carbons and 14 hydrogens

D. Since there are 6 carbons, there should be 2n+2=14 hydrogens. So, there is no deficit. Therefore, there will be no double bonds in this molecule. c is incorrect because there are 5 carbons, there should be 2n+2=12 hydrogens. Since only 8 hydrogens is present, there is a deficit of 4 hydrogens. The ring requires a deficit of 2 hydrogens, and this means there are still 2 hydrogens not accounted for. So, a double bonded oxygen could account for these hydrogens.

Substituent A is axial, and substituent B next to it is cis and is a large substituent. Which type of bond would substituent B occupy? A .chair B .boat C . axial D .equatorial

D. So, if the substituent is axial, and substituent on the adjacent carbon is cis, it has to be equatorial. A large substituent will nearly always occupy an equatorial position.

What is the name of this functional group? H—O— A .alkoxy B epoxy C .benzyl D . hydroxy

D. The "OH" group is the alcohol or hydroxy group.

A Grignard Reagent will react with a carbonyl compound at the A .at any of the positions B .alpha-beta unsaturated position C .alpha carbon D . carbonyl carbon

D. The Grignard Reagent, RMgX, is a nucleophile and will add to the carbonyl position of the ketone/aldehyde: RMgX+ R'-CO-R"→ →R'-C(=R)-R"

The hybridization of the carbon being attacked by the nucleophile in an SN1 reaction will vary from A . sp2 to sp2 B .sp2to sp3to sp2 C .sp3 to sp3 D .sp3 to sp2 to sp3

D. The SN1 is called substitution nucleophilic monomolecular. This is a first-order reaction, and there is one species in the rate equation and in the critical step.

Which is true regarding a Glycosidic bond? A .the carbonyl carbon is not part of the bond B . found in the straight-chain form C .is an alcohol bond D .forms an acetal

D. The acetal is formed with the anomeric carbon and a hydroxyl group...an acetal results. The glycosidic bond is only found in the ring form of the carbohydrate.

A primary alcohol when reacted with potassium permanganate will form a(n) A .ether B .aldehyde C .ketone D . carboxylic acid

D. The alcohol would be converted to an aldehyde and then the carboxylic acid.

The anomeric carbon, as found in carbohydrates, is A .the second carbon B .not optically active C .found in the straight chain form only D . located at the carbonyl carbon

D. The anomeric carbon is the carbonyl carbon of the straight chain form. When the ring is formed, the anomeric carbon is formed and it now becomes a chiral center.

The anomeric carbon, as found in carbohydrates, is A the second carbon B .not optically active C .found in the straight chain form only D . located at the carbonyl carbon

D. The anomeric carbon is the carbonyl carbon of the straight chain form. When the ring is formed, the anomeric carbon is formed and it now becomes a chiral center.

In an IR spectrum, the Aromatic absorptions are best described as A .broad B .sharp C .weak D . medium (strength)

D. The aromatic, double bond, absorptions are described as medium strength.

The boiling point of alkanes ______________ with increasing molecular mass because of __________________ A .decreases, dipole forces B .decreases, dispersive forces C .increases, dipole forces D . increases, dispersive forces

D. The boiling point will increase as dispersive forces increase. Dispersive forces increase as mass increases. Alkanes do not have dipole forces. This is a dichotomy of options question.

For a bond between any two atoms, bond length will be shortest for a A .bond between atoms from the second period B .single bonds C .double bonds D . triple bonds

D. The bond length is determined by the two atoms making up the bond. A rough rule of thumb is to take the sum of the atomic radii as an estimate of the bond length. Single bonds will be longer than double bonds, which will be longer than triple bonds. So, you can estimate the bond length by knowing the relative atomic radii and the saturation (single bond, or double bond or triple bond) present.

Bromine is a neutral molecule, then bromine A .cannot be nucleophilic B . cannot be electrophilic C .cannot be nucleophilic nor electrophilic D .has both nucleophilic and electrophilic components

D. The bromine molecule is both electrophilic and nucleophilic. If it comes near a negative source, like a double bond, this induces one of the bromines to be positive, which would be electrophilic. Once the Br+ is taken, this leaves Br- which is negative and nucleophilic

The geometric shape of the orbitals of the carbonyl carbon is A .Hexagonal B . Linear C .tetrahedral D .planar

D. The carbonyl has the sp2 hybridization which is planar.

At the pI of an amino acid A .the amino acid will migrate in an external electric field B .the carboxyl group is neutral C .the amino group is negatively charged D . the amino acid is charged but neutral

D. The carboxylic acid is negative and the amino group is positive at the pI:

The ________form of cyclohexane is more stable than the ________ because of less _________ A .boat, chair, ring strains B .boat, chair, steric and torsional strains C .chair, boat, ring strains D . chair, boat, steric and torsional strains

D. The chair conformation is by far the more stable form. The boat form is destabilized by the steric interactions between the 1 and 4 substituents, as well as other torsional strain and steric strain interactions such as those between other substituents. The chair form has two distinct substituents on each carbon called axial position (A) and equatorial position (E). The axial substituents are parallel to the vertical axis of the molecule, and the equatorial substituents are at an angle to the axis. Normally, the two chair forms rapidly interconvert. But, substituents may favor one conformer over another. Large substituents prefer the equatorial positions. A large group, like tert-butyl, can lock the molecule with itself in an equatorial position. Also, 1,3-diaxial interactions destabilize a conformer as compared to 1,3-equatorial interactions. These effects are steric effects. Also, cis-1,2-gauche interactions between large groups will destabilize the conformer.

In the chair form of cyclohexane, large groups will usually be on the __________ bonds. A .1,4 B .1,2 C .axial D . equatorial

D. The chair form has two distinct substituents on each carbon called axial position (A) and equatorial position (E). The axial substituents are parallel to the vertical axis of the molecule, and the equatorial substituents are at an angle to the axis. Normally, the two chair forms rapidly interconvert. But, substituents may favor one conformer over another. Large substituents prefer the equatorial positions. A large group, like tert-butyl, can lock the molecule with itself in an equatorial position. Also, 1,3-diaxial interactions destabilize a conformer as compared to 1,3-equatorial interactions. These effects are steric effects. Also, cis-1,2-gauche interactions between large groups will destabilize the conformer.

In the electrophilic substitution reaction of carbonyls, substitution occurs at the A .the carbonyl oxygen B .the beta carbon C . the carbonyl carbon D .the alpha carbon

D. The electrophilic substitution of carbonyls is at the enol double bond of the carbonyl. The electrophile, the positive part of the substrate, adds at the alpha carbon...this allows the carbonyl carbon to reform

The Wittig reaction results in the A .loss of water from the carbonyl B loss of carbon dioxide from the carbonyl C .substitution of a double bond to nitrogen for the carbonyl double bond D . substitution of a double bond to a carbon for the carbonyl double bond

D. The essence of the Wittig reaction is the substitution of a double bonded carbon for the carbonyl oxygen. The reaction is very complex and will most likely be provided to you if needed. The net result is: R-CO-R' (carbonyl) +R-"P+(Ph)3(phosphorus ylide (Ph=phenyl)→→R-C(=R")-R' (alkene)

The aldol condensation will usually result in a product that A .has unconjugated double bonds B .has a triple bonded carbon C .has one double bond D . has conjugated double bonds

D. The first step is the attack of the enolic carbon, Ce, on the carbonyl carbon, Cc, forming the tetrahedral addition product. Then water, HOH, is lost to form the double bond between the Ce and Cc. The other, conjugated double bond, is the remaining carbonyl next to the Ce. *The final product will have conjugated double bonds between the enolic carbon and carbonyl remaining.

A primary amine reacts with a ketone/aldehyde to form a(n) A . imide B .amide C .enamine D .imine

D. The first step is the reaction of the amine to form a tetrahedral addition product with the carbonyl. The second step is the loss of water to form the imine (which has the nitrogen double bonded to the carbonyl carbon). Both of the H's of water comes from the primary amine.

A glycosidic bond A .results in the addition of water to the sugars B .destroys the chirality of the carbon C .is an hemiacetal linkage D . is formed between two sugar units with the loss of water

D. The formation of the glycosidic linkage is from one of the -OH's attacks a carbon of the other carbohydrate. This will be an acetal (R-O-CH-O-R).

Amino acids with hydroxyl side groups tend to function as ___________ in catalytic reactions. A .electrophiles B .acids C .electrophiles or nucleophiles D .nucleophiles

D. The hydroxyl group is O-H. The oxygen has two free pair of electrons... these will function as nucleophiles. Although, the O-H can function as an acid or base, and it may do in various reactions, its role as a nucleophile is more frequent. So, this is the best option.

The primary reaction of all carboxylic acid derivatives is A carbonyl oxygen nucleophilic substitution B .carbonyl carbon nucleophilic addition C .carbonyl carbon electrophilic substitution D . carbonyl carbon nucleophilic substitution

D. The main reaction is nucleophilic attack on the carbonyl carbon. The carbonyl carbon is very electropositive due to the two oxygens (or one oxygen and another electronegative group, eg M below, attached and due to resonance with them. Resonance allows for stabilization of the intermediates and then the noncarbonyl group (M) is displaced:

In a fractional distillation setup, A .the highest boiling liquid is at the top of the distilling column and the lowest boiling liquid is at the bottom B .there is no packing in the fractionating column C .the highest boiling liquid is the first to drip into the collection flask D . there is better separation of liquids with close boiling points than in a simple distillation setup

D. The multiple steps allows much better separation of components as compared to simple distillation.

Which structure of proteins does NOT have an INCORRECT description? A .primary-hydrogen bonds B . secondary-sequence of amino acids C .tertiary-hydrophobic amino acids on the surface D .quaternary-two or more protein units

D. The quaternary structure is characterized by having two or more units present. The double negative makes this a positive. All you have to do is find the one which has the correct association

Nonpolar solvents enhance reaction (s) of this type. A .SN1 B .SN2 C .both D . neither

D. The solvent has to be polar. This is because the nucleophile and leaving group are usually charged or minimally are polar.

Melting point (MP) increases when A .electronegativity decreases B molecular mass decreases C .strength of the intermolecular forces decrease D . strength of the intermolecular forces increase

D. The strength of molecular forces is the main determiner of the MP...as they increase the MP increases.

What is the correct suffix for lactone? A .-al B .-amide C .-oate D . correct suffix not listed

D. The suffix for a lactone, which is a cylic ester, is lactone.

Steric strain would be greatest for which of the following groups? A .sec-butyl B .hydrogen C .iso-propyl D . tert-butyl

D. The tert-butyl group ((CH3)3C-) is by the largest group of those listed in terms of steric effects.

What is the hybridization of carbons a, b and d in this molecule? Propane,CaH3CbH2CdH3 A .a-sp3, b-sp2, d-sp3 B .a-sp3, b-sp, d-sp3 C .a-sp2, b-sp3, d-sp2 D . a-sp3, b-sp3, d-sp3

D. There are 3 C's. Then, for a saturated molecule, there is expected to be 2n+2 =2(3)+2=8 hydrogens. The molecule does have 8 (3+2+3) H's. So, this is fully saturated. Saturated C's are all sp3.

What term best describes this molecule? ø-NH2 (where ø=benzene ring) A .quaternary B .tertiary C .secondary D . primary

D. There is one substituent on the nitrogen, so it is primary. It also has hydrogen atoms on the nitrogen which allows hydrogen bonding between molecules. This has the common name of aniline. It may also be called phenylamine.

The most unfavorable energy conformation of two substituents on two adjacent carbons occurs when the substituents are: A .staggered B .facing each other C .anti D . eclipsed

D. Think of the hour designations and hands (but being on adjacent atoms) on a clock. The eclipsed conformation, can be of individual substituents or the total conformation, occurs when both hands are at the same number. This conformation has the highest energy associated with steric strain (due to the electronic bulk of the substituent) and torsional strain (due to the electrical repulsions of the bonds). Notice that if a substituent is at the 12 position on one atom, the positions of 4 and 8 will be the other eclipsed positions on the other atom... this is for the four bonded atom like carbon.

Which is the best description of this group, C—O, in the IR spectrum? A .broad B .sharp C .weak D . medium (strength)

D. This absorption typically occurs at about 1100 cm-1.

The measure of relative concentrations of the solute in two immiscible liquids in contact is A . Partition coefficient B .Distribution coefficient C .Ratio to the front (Rf) D .Both A and B

D. This describes an extraction process. Either the partition coefficient or distribution coefficient are used. It is the ratio of the concentration of the solute in one solvent to the other solvent

Which of the following carbon-hydrogen bonds would be expected to be the shortest? A H3C—H B . CH3CH=CH—H C .CH3C=C—H D .CH3CΞC—H

D. This hybrid, sp, has the greatest amount of s character. It would be expected to be the shortest and strongest of these C-H bonds. The greater the s character, the shorter the bond and the stronger the bond.

Which of the following results when a secondary alcohol reacts with SOCl2? A .intermediate carbocation formed and alkene results B . intermediate carbocation formed and substitution of OH results C .no intermediate carbocation formed and alkene results D .no intermediate carbocation formed and substitution of OH results

D. This is a Sn2 reaction...there is no carbocation formed. The halide, Cl, is substituted for the OH.

An amino acid with this side chain, H2NCH2CH2CH2CH2-, would be found at/on the A .equally on the inner or outside surface of protein B .inner regions of protein C .active site of acid catalysis D . active site of basic catalysis

D. This is a basic and polar amino acid. It could participate in basic catalysis.

An amino acid with this side chain, H2N—C(NH)—NH-CH2CH2CH2—, would be found at/on the A .anywhere on the protein (out or in) B .inner regions of protein C . active site of acid catalysis D .active site of basic catalysis

D. This is a basic and polar molecule. It can participate in basic catalysis.

The preferred position for a large substituent in a cyclohexane molecule. A .chair B .boat C .axial D . equatorial

D. This is a bond position in a chair conformation of cyclohexane...it is the preferred position for a large substituent to decrease steric strain.

Multiple subunits are a key to this level of protein structure: A . primary structure B .secondary structure C .tertiary structure D .quaternary structure

D. This is a protein with multiple subunits. It is held together by noncovalent bonds.

In the Pinacol Rearrangement A .the product formed will be a carboxylic acid B .the product formed will be an di-hydroxy alcohol C .carbocations are not formed during the reaction D . an alkyl shift occurs

D. This is an intramolecular shift reaction. The immediate carbocation is converted to another carbocation by the intramolecular shift of an alkyl group...this shift allows the formation of the carbonyl group.

An alcohol will have peaks on the infrared spectroscopy at A .1750 cm-1and 2250 cm-1 B .3500 cm-1and 2250 cm-1 C .1750 cm-1and 1100 cm-1 D . 3500 cm-1 and 1100 cm-1

D. This is consistent with a -C-O- group and an -O-H group which can be an alcohol (R-CH2-OH)

An alcohol will have peaks on the infrared spectroscopy at A .1750 cm-1and 2250 cm-1 B .3500 cm-1and 2250 cm-1 C .1750 cm-1and 1100 cm-1 D . 3500 cm-1 and 1100 cm-1

D. This is consistent with a -C-O- group and an -O-H group which can be an alcohol (R-CH2-OH).

Where is the absorption, given in wave numbers, of the Alkyne (C≡C—H) hydrogen? A .2750-2850 B . 2850-2960 C .3020-3100 D .3300

D. This is the absorption of the vinyl hydrogen (C=C-H) and aromatic hydrogens which are moderate and sharp. See the discussion of the correct option.

When the vapour pressure (VP) of a liquid reaches the external atmospheric pressure (EP), A .plasma formation begins B .vaporization begins C .sublimation begins D . boiling begins

D. This is the definition of the boiling point of a substance: the temperature at which the VP=EP

CH3COCH2CH3: what is the suffix of the functional group of this molecule? A .-yne B .-ol C .ether D . -one

D. This is the ketone group...the carbon-oxygen is double bonded

Which of the following reagents may be best used to protect the alcohol functional group in a reaction A . SOCl2 B .acetic anhydride C .hydronium ion D .chlorotrimethylsilane

D. This will block and then is readily removed as contrasted to some of the other species shown

The anomeric carbon A .is the second carbon B .is not optically active C .is found in the straight chain form only D . is located at the carbonyl carbon

D. the anomeric carbon is the "1" below. This was the aldehyde of the glucose. There is also an anomer carbon at the far right by the hemiacetal bond (OH going up and to the right was the carbonyl oxygen).

Name this compound: H3C—NH2. A . 1-Methylamine B .Aniline C .Methamine D .Methyl amine

D. this is naming each functional group: the methyl for one carbon and the amine for the -NH2.

Lipid soluble side chain A .NADH B .FADH2 C .ATP D . ubiquinone

D. this is part of the ETS and transfers electrons. Its side chain is hydrocarbon making it lipid soluble. It is also called CoQ10.

What is the name of this functional group? Φ—O- (ø=benzene ring) A .alkoxy B .oxo C .epoxy D . phenoxy

D.The base group is the phenyl. When an oxygen is attached to it, it is like an alkoxy but with a phenyl group...it becomes a phenoxy.

Which statement is true about a Phospholipid? A .hydrolysis with an alkali base yields glycerol and soap(s) B .hydrolysis will yield one long chain fatty acid and one long chain alcohol C .contains no double bonds and is solid at room temperature D . hydrolysis would yield glycerol, a saturated fatty acid, an unsaturated fatty acid and another compound

D.This is a phospholipid. They are made of glycerol bonded to a saturated fatty acid, an unsaturated fatty acid and then a nitrogen phosphate compound, such as choline, at the third hydroxyl. The second carbon is chiral. When hydrolyzed, glycerol, a saturated fatty acid, an unsaturated fatty acid and a nitrogen phosphated compound results.

Alkene formation: dehydrohalogenation may proceed by either E1 or E2 in the E1/E2 reaction the halogen drops off in the first step and a hydrogen is removed in the second step, in the E1/E2 reaction, the base removes a proton from the carbon next to the halogen containing carbon and the halogen drops off leaving an alkene

E1, E2

E1/E2 is with a weak base and E1/E2 is with a strong bulky base

E1, E2

aromatic rings are Electron-withdrawing/electron-donating which increase/decrease basicity

Electron-withdrawing, decreases-(through the sigma bond system by induction and not resonance)

carbonyls adjacent to the nitrogen are Electron-withdrawing/electron-donating which increase/decrease basicity

Electron-withdrawing, decreases-(through the sigma bond system by induction and not resonance)

halides are Electron-withdrawing/electron-donating which increase/decrease basicity

Electron-withdrawing, decreases-(through the sigma bond system by induction and not resonance)

nitro are Electron-withdrawing/electron-donating which increase/decrease basicity

Electron-withdrawing, decreases-(through the sigma bond system by induction and not resonance)

what is an epimer

Epimers are compounds that differ at one of the asymmetric carbons:

name the functional group R - COOR' as in carboxylic acid have -OR' instead of -OH

Ester(-oate)

extraction is the process of doing what?

Extraction is the process of removing a solute from one liquid solvent and transferring it into a second solvent that is immiscible with the first.

true/false distillation, which typically results in only one step, results in a complete separation of the liquids.

False: distillation, which typically results in only one step, may not result in a complete separation of the liquids.

salts if fatty acids are known as _____

If a strong base is used to hydrolyze the ester linkages, the salts of the fatty acids result; this process is called saponification and the salts of fatty acids are known as soaps.

saponification?

If a strong base is used to hydrolyze the ester linkages, the salts of the fatty acids result; this process is called saponification and the salts of fatty acids are known as soaps.

R-CO-NH-COR' as in carboxylic acid have R'COO- replaces the -OH R and R' may be same/different

Imide

The effect of an electronegative group on the chemical shift also depends on its distance from the protons....how explain with methanol as an example?

In methanol, the hydroxyl proton is separated from oxy- gen by one bond, and its chemical shift is d 4.8. The methyl protons are separated from oxygen by two bonds, and their chemical shift is d 3.4. In general, the effect of an electron-withdrawing substituent decreases with increasing distance, and the effects are usually negligible on protons that are separated from the electronegative group by four or more bonds.

There are four main types of spectroscopy used in the identification of organic compounds: 3.______ Spectroscopy This is used to determine the functional groups.

Infrared

what is specific rotation?

It is the rotation of plane polarized light by the optical isomer

name the functional group R - CO - R' where R and R' may be same/different the O is double bonded (a carbonyl)

Ketone (-one)

There are four main types of spectroscopy used in the identification of organic compounds: 4. _____ Spectroscopy This is used to determine the carbon-hydrogen skeleton.

NMR

Nitriles are made by reacting ___ with an _____ _____ where the CN- replaces the halide.

NaCN, alkyl halide

In both the TMS ether and the Tos ether and in the reactions with PBr3 (phosphorus tribromide) and SOCl2 (thionyl chloride), it is the ____ bond of the alcohol that is broken and not the ____ bond.

O-H, R-O

Primary and secondary alcohols may be converted to alkyl halides by using ____ and _____ via SN2/SN1 reactions

PBr3 and SOCl2, SN2

____is a unique AA, being the only secondary amine; all others are primary amines.

Proline

what occurs in the haloform reaction

RCOCH3+3X2+OH- (x-halogen) when a base is used with a methyl ketone (RCOCH3) the alpha carbon will become completely halogenated . this trihalo product reacts further with the base to produce a carboxylic acid and a haloform (chloroform CHCl3, bromoform CHBr3, iodoform CHI3)

f the line is counterclockwise, the absolute configuration is S/R as for Ca above: if the line is clockwise, the absolute configuration is S/R.

S, R

Tertiary alcohols react with the acids (e.g., HCl or HBr) by an SN2/SN1 mechanism with an intermediatecarbocation.

SN1

does this describe an SN1 reaction of SN2 reaction? The stability of the leaving group is also important, but the strength of the nucleophile is not (because it is not part of the rate-limiting step).

SN1

polar protic solvents (polar solvents that hydrogen bond) increase the rate of (sn1/sn2) reactions while polar aprotic solvents increase the rate of (SN1/SN2) reactions

SN1, SN2 polar protic is better for SN1 because it can better stabilize the nucleophile and carbocation polar aprotic is better for SN2 because it doesn't form strong bonds with ions

whats a stereoisomer

Stereoisomers have the same carbon structure, the same functional groups, and the same atoms attached to each other.

Nucleophiles add to the carbonyl carbon in the nucleophilic addition reaction. The first step of the reaction results in the formation of the ______

TAP: tetrahedral addition product:

The boiling point (BP) of a liquid decreases if the external pressure is A . raised above 1atm B .lowered below 1 atm C .raised from any value D .lowered from any value

The BP is when the vapor pressure (VP) of the liquid equals the external pressure (EP). So, if the EP is increased, the temperature will have to be higher, ie the BP higher, for VP to equal EP. If the EP is decreased, then the VP will equal the EP at a temperature and the BP will be lower. The 1 atm is for a normal BP only.

what occurs in a pinacol rearrangement

The acid protonates one of the hydroxyl groups, making it positive, and this is now a good leaving group; it leaves, leaving the Pinacol carbocation The Pinacol carbocation is stable but a shift is still possible for a methyl group to the carbocation. This results in the intermediate, with the positive charge now on the carbon with the remaining hydroxyl group; this is a very stable carbocation because of the resonance stabilization of the free electron pairs on the oxygen. The hydrogen of the OH leaves and the ketone group of the Pinacolone is formed. This reaction may occur with any similar arrangement of hydroxyl groups.

what does the pKa represent for a titration curve

The pKa is the pH at which the acid is 50% ionized (i.e., exists 50% as its acid and 50% as its conjugate base).

the free pair of electrons on nitrogen can acts as what?

The electrons act as nucleophiles. They can also act as a Lewis Base (an electron pair donator) and as a Bronsted Base (a proton acceptor):

Because of the great variability in how molecules are fragmented, each MS results in a unique pattern or spectrum (a fingerprint)...what determines the fragmentation?

The pattern of fragmenting of the molecules depends on how well a fragment can stabilize a positive charge (by resonance or induction) and how strong the molecular bonds are.

what bond is formed in an beta pleated sheets aka whats the key feature

The key feature of the beta-pleated sheet is the presence of interprotein hydrogen bonds. The hydrogen bonds are formed between two protein chains and again between the carbonyl carbon and the amide -NH.

what molecules are most likely to undergo decarboxylation

The molecules that will undergo this reaction are mainly the beta diacids (or esters) and the alpha keto acids and beta leto acids

in a combustion reaction, whats the equation for the number of oxygen needed where n is the number if carbons

The number of O2 needed is (3n + 1)/2, where "n" is the number of carbons.

Recrystallization- The boiling point of the solvent should be less than its melting point. why?

This prevents the substance "melting" in the solvent, which results in oil formation

There are four main types of spectroscopy used in the identification of organic compounds: 1. ______ Spectroscopy This is used to identify the presence of double bonds.

Ultraviolet

hydrogenation is an example of an addition reaction and in order for it to occur, what does it need?

a heterogeneous catalysts which is a catalyst that exists in a different phase than the reactant or products

Acid anhydrides are made from carboxylic acids by removing what

a molecule of water.

what does it mean for a nucleus to be in resonance

a nucleus that is subjected to this perfect combination of magnetic field strength and electromagnetic radiation frequency

how does distillation work?

a solution of two volatile liquids with boiling point differences of 20 degrees C or more may be separated by slow boiling: the compound with the lower boiling point (higher vapor pressure) will boil off and can be captured and condensed in a cool tube

what is an azeotrope

a solution with an exact ratio of the two liquids from a distillation process occurs when the solution of two volatile liquids exhibits a positive deviation from raoults law and the solution will boil at a lower temperature than either pure compound

how can you can tell the difference between a strong base and a weak base

a strong base will have a negative charge while a weak base will not

Carbonyls The hydrogens on the alpha-carbon are called alpha-hydrogens. The alpha-hydrogens are basic/acidic and why?

acidic because of electron withdrawal by the carbonyl group and the stabilization of the resultant anion:

Amide Formation and Chemistry: Carboxylic acid results if the conditions are basic/acidic. The salt of the acid results if the conditions are basic/acidic.

acidic, basic

in regards to benzene when an electron donating group in the r position then it activates/deactivates the ring and directs any new substituents to the (meta/ortho/para) position (s)

activates, ortho and para positions *halogens are an exception to the rule- they are electron withdrawing, but they direct new substituents to the ortho/para positions

derivatives of carboxylic acids contain _____ group

acyl (R-C=O-)

list from least stable to most stable for carboxylic acid derivatives 1. acyl chloride 2. acid anhydride 3. carboxylic acid 4. ester 5. amide

acyl chloride< acid anhydride< carboxylic acid< ester< amide

list from most reactive to least reactive for carboxylic acid derivatives 1. acyl chloride 2. acid anhydride 3. carboxylic acid 4. ester 5. amide

acyl chloride> acid anhydride> carboxylic acid> ester> amide

To make an ester, an ____or ___ion is used.

alcohol, alkoxide

Acetals (for aldehydes) (ketals for ketones) and hemiacetals (for aldehydes)(hemiketals for ketones) form by reactions between what 2 things? and it is a type of (nucleophilic/electrophilic) reaction

alcohols and aldehydes or ketones, nucleophilic

Rosenmund Reduction of acid chlorides with Pd-BaSO4/H2 to yield an ____

aldehyde

name the functional group R-COH

aldehyde *the O is double bonded to carbon (a carbonyl)

The hydrogenation reaction can be used to determine relative stability of the ______.

alkenes *The reaction has a negative enthalpy. The more negative the enthalpy, the less stable the reacting alkene. Substituted alkenes and trans vs cis alkenes tend to be more stable.

halogens are much more reactive towards alkenes/alkanes why?

alkenes halogens will not react with alkanes without light or heat but alkenes will

Hofmann Elimination forms _____ from ______.

alkenes, amines

name the functional group R - X (where X is a halogen)

alkyl halide

name the functional group R -c ≡ C - R where R may be a carbon group or a H

alkyne (-yne)

halogens add to ketones at the ______ ______ in the presence of an acid or base

alpha carbon

what type of bonding is found in secondary protein structure

alpha helix and beta pleated sheets and interchain of hydrogen bonds

In starch and glycogen, the glucoses are bound by ______ glycosidic bonds to form the polymer.

alpha-1,4

name the functional group R-CONH2

amide as in carboxylic acid have -NH2 instead of -OH R groups may replace H's on N

how are amides formed?

amides are formed when an amine acting as a nucleophile substitutes at the carbonyl of the a carboxylic acid or one of its derivatives

To make an amide, an ____is used.

amine

aniline is a benzene ring with ______ attached to the R position

amine

name the functional group R-NH2 R groups may replace the H's on N

amine

name the functional group R-NH2

amine- R groups may replace the H's on N

amines are derivatives of ________

ammonia

1. ultraviolet Spectroscopy This is used to identify the presence of ____ ____

double bonds.

using DIBAH, will convert an ester or a nitrile to what?

an aldehyde

hydrogens with less shielding tend to have peaks (upfield/downfield) or to the left

downfield

halogenation of an alkene is (syn-additon or anti addition)

anti addition because when the double bond disappears, the halogens are attached on opposites sides not same side

For benzene ring with one substituent, para means that a hydrogen is attached where?

anti to the substituent (aka straight down or up vertical ways)

tautomerization?

are constitutional isomers of organic compounds that readily interconvert by a chemical reaction called tautomerization

Chromatography may also be used to do what?

as a very specific method to not only identify but also separate and isolate molecules.

how can aldehyde products be easily distinguished fem ketone products

by the lone hydrogen

When a fat is hydrolyzed with a strong base, the product(s) is (are) A . cholesterol, 3 salts of fatty acids B . cholesterol, 3 fatty acids C . glycerol, 3 salts of fatty acids D . glycerol, 3 fatty acids

Number of optical isomers of glucose (C6H12O6) A .2 B .4 C .16 D . 32

c. Glucose has four chiral carbons. The number of optical isomers is given by 2n, where n=the number of chiral carbons. Then 24=16.

for electrophoresis if the masses are equal then the movement if inversely proportional to ________

charge

Electrophoresis is a method used to separate what?

charged molecules.Most of these molecules will either contain a nitrogen atom or a carboxylic acid This method is used extensively to separate and identify amino acids, proteins and nucleic acids.

sun-addition (same side addition) of alkynes creates a cis/trans alkene

cis

is a conjugated double bond more stable than a isolated double bond

conjugated (Conjugated double bonds have lower energies for electronic transitions and will appear in UV spectra.)

In NMR the frequency of the electromagnetic radiation is (constant/ varied) while the magnetic field is (constant/varied)

constant, varied

The most common ring is_____. One measure of stability of the ring systems is their heats of combustion. Higher heats of combustion mean more stable/unstable rings.

cyclohexane, unstable

Groups that donate electrons via resonance to the benzene ring (i.e., activating groups) increase/decrease the acidity.

decrease

groups that withdraw the density of the electron pair from the nitrogen through resonance increases/decrease base strength (the other factor in the lack of base strength of amides).

decrease

for amines electron withdrawing groups tend to increase/decrease basicity while electron donating groups tend to increase/decrease basicity

decrease, increase

In general, the effect of an electron-withdrawing substituent increases/decreases with increasing distance, and the effects are usually negligible on protons that are separated from the electronegative group by four or more bonds.

decreases

The base strength of amines increases/decreases as the number of electron-withdrawing groups attached to the nitrogen increases.

decreases

The polarity of a functional group (increases/decreases) significantly as the carbon chain reaches 6 carbons and beyond

decreases

distillation- temperature increases/decreases as the (fractionating) column is ascended.

decreases

for alkenes and alkanes, branching will increase/decrease boiling point

decreases

electron withdrawing (decreases/increases) shielding and decreases field strength which results in (upfield/downfield)

decreases, downfield

what does Polycyclic mean?

denotes that more than one ring is fused together.

8ppm corresponds to (upfield/downfield) magnetic field strength while 1ppm corresponds to (upfield/downfield) magnetic field

downfield, upfield

when thinking about nitrous acid (weak acid), and primary amines, just think _____ ion and remember that only ______ amines work

diazonium ion, aromatic

to find the Rf factor for paper chromatography, you would take a ratio of _____/_____

distance travelled by the component/ distance traveled by the solvent

what method does this describe? a solution of two volatile liquids with boiling point differences of 20 degrees C or more may be separated by slow boiling

distillation

amines like to donate/accept their negative electrons so they tend to stabilize carbocations when they are part of the same molecule

donate

Double bonds undergo several other important reactions. One is an electrophilic addition of bromine (Br2) in the dark. This may be used to identify the presence of what

double bonds *An aromatic compound will not react with bromine in the dark. A regular alkane or aromatic will not react with bromine in the dark without a catalyst.

torsional strain can be seen when structures are (eclipsed/staggered)

eclipsed results in a higher energy state and less stability of the conformer.

benzene is an electron donating/electron withdrawing

electron withdrawing

the double bond of an alkene is an electron rich environment so it attracts nucleophiles/electrophiles

electrophiles

Alkenes are formed by elimination/substitution reactions.

elimination

Secondary amine reacts to form an ______(double bond formation not possible from the N to the carbonyl carbon, and an alpha hydrogen is lost to form a double bond between the carbonyl and alpha carbon):

enamine

Optical isomers that are also mirror images of each other and are nonsuperimposable are called enantiomers/diastereomers. Optical isomers that are not mirror images of each other are called enantiomers/diastereomers.

enantiomer, diastereomers

what can a nor spectrometer detect?

energy absorption of a ucleus in resonance

The fat has three fatty acids bonded to the glycerol in____ linkages.

ester

name the functional group R-COOR'

ester as in carboxylic acid have -OR' instead of -OH

name the functional group R - O - R' where R and R' may be the same or different

ether

name the functional group R - O - R'

ether where R and R' may be the same or different

phosphoric acids react with alcohols to produce what

ethers

Fatty acids are long-chained, even/odd-numbered carbon carboxylic acids. why?

even, they are mainly even numbered because they are made from building blocks of acetyl CoA, which has two carbons

crystallization of salts is (exothermic/ endothermic)

exothermic

hydrogenation is (exothermic/endothermic) with a (high/low) energy of activation

exothermic, high

the more/less substituted the alkene, the more/less thermodynamically stable it is

true/false The best solvent for recrystallization will have a boiling point higher than the melting point of the substance to be isolated

false If the boiling point of the solvent is higher than the melting point of the substance to be isolated, then the substance will form an oil at higher temperature and will not be able to be separated.

true/false The best solvent for recrystallization will have impurities soluble at high temperatures

false Impurities should be insoluble at higher temperatures so they can be filtered off.

true/false The best solvent for recrystallization will have have the desired substance be highly soluble at low temperatures

false The desired substance should be insoluble at low temperatures. It helps to impurities soluble at lower temperatures.

true/false aldehydes and ketones have higher boiling points than corresponding alcohols

false aldehydes and ketones have lower boiling points than corresponding alcohols because they cannot hydrogen bond with themselves

true/false aldol condensation is catalyzed by a base only

false it can be catalyzed by an acid or a base

true/false An ideal mixture of liquids means the liquids are immiscible in all proportions and have no intermolecular forces or interactions.

false: An ideal mixture of liquids means the liquids are miscible in all proportions and have no intermolecular forces or interactions.

true/false Aromatic rings are generally susceptible to nucleophilic attack.

false: Aromatic rings are generally not susceptible to nucleophilic attack. The rings are electronegative and not electropositive. Since nucleophiles have negative character, they are attracted to the negative character rings.

true/false mess compounds rotate plane polarized light why or why not

false: Due to the plane of symmetry, it does not rotate plane polarized light. Essentially, the two symmetric halves rotate light in opposite directions and cancel each other out.

true/false broad melting points mean the substance is pure

false: Narrow melting points mean the substance is pure

Infrared Spectroscopy This is used to determine the ____ ______

functional groups.

The common disacharides are sucrose which is made with what 2 things? in an _____ bond),

glucose and fructose, alpha-1,2

lactose, a disaccharide made with _____ and ______ in an _____ bond

glucose and galactose in a beta-1,4 bond

glucose/fructose is an aldehyde and glucose/fructose is a ketone

glucose, fructose

______is unique in being the only amino acid that is not chiral (optically active).

glycine

oxidation of alkenes may produce _____ or may cleave the alkene at the double bond

glycols (hydroxyl groups on adjacent carbons)

The sugars bond together via_____ bonds

glycosidic

electron withdrawing effects and polarizability make (good/bad) leaving groups

good

The greater the positive or negative charge on a molecule, the greater/Smaller will be its movement toward the appropriate poles.

greater

the stronger the energy field, the (greater/smaller) the difference between these energy states

greater

Tosylates act like _____and are replaced by nucleophiles.

halides , nucleophiles

alkyl halide is a carbon group bonded to a ______

halogen (chlorine, bromine, iodine, or fluorine).

high/low temperatures and concentrated/dilute acid drive hydration towards the alkene

high, concentrated

Recrystallization-the solvent should be volatile (high/low vapor pressure) at high/low temperatures, so that the solvent can be effectively removed from the crystals.

high, low

Mass spectroscopy: Groups that can better stabilize a positive charge (as in the carbocation stability series) would be expected to have a higher/lower frequency or intensity

higher

Polar molecules have (higher/lower) boiling points than non polar ones

higher

The higher/lower the pKa of the salt, the stronger the base strength of the parent amine.

higher

The saturated fatty acids tend to have higher/lower melting points and are usually solid.

higher

Amines that have hydrogens attached will have higher/lower boiling points (BPs) than corresponding alkanes/alkenes or amines without hydrogens attached. Melting and boiling points are higher/lower than those of the corresponding alkanes because of the polarity.

higher, higher

alcohols have higher/lower melting points and higher /lower boiling points than alkanes why?

higher, higher because of hydrogen bonding -H+ bonds increase intermolecular forces which must be overcome by phase changes

amines have higher/lower boiling points than alkanes but higher/lower boiling points than alcohols

higher, lower

aldehydes and ketones have (higher/lower) boiling points and are more/less polar than alkanes and alkenes

higher, more

what is the sequence of increasing steric interactions for these compounds -hydrogen -tert-butyl -methyl -ethyl -isopropyl

hydrogen (essentially none) < methyl < ethyl < isopropyl < tert-butyl

what type of bonding/forces exists in tertiary structure

hydrogen-bonding and polar and hydrophobic interactions. nonpolar amino acids tend to be inside the tertiary structure and the polar amino acids tend to be on the surface. disulfide bonds can hold chains, or portions of the same chain, in a covalent bond link. folding of the protein chain results in formation of the active site of enzymes or the binding, receptor sites for various molecules that noncovalently bond to the protein.

NMR is concerned with what?

hydrogens

Reduction in organic chemistry refers to the addition of ______

hydrogens

The acidic amino acids are hydrophilic/hydrophobic and can serve as sites of hydrogen ion donation — as in acid catalysis

hydrophilic

The basic amino acids are also hydrophilic/hydrophobic, but can serve in locations where base or nucleophile functions are required

hydrophilic

the tail in a phospholipid is (hydrophobic/hydrophilic) while the head is (hydrophobic/hydrophilic)

hydrophobic, hydrophilic

phenol is a benzene ring with ______ attached to the R position

hydroxyl

what is anti markovinikov addition

if peroxides are present (ROOR) the bromine, not the hydrogen will add to the least substituted carbon

name the functional group R-CO-NH-COR'

imide as in carboxylic acid a R'COO- replaces the -OH R and R' may be same/different

primary amine reacts to form an ______(double bond formed to carbonyl carbon)

imine

amines react with aldehydes and ketones losing water to produce ____ and ____

imines, examines

whats saytzeff rules?

in regards to the formation of alkene and states that the major product of elimination will be the most substituted alkene

An increase/decrease in the electronegativity of the attached groups will lower the opposing fields and result in deshielding.

increase

Increasing temperature will increase/decrease solubility, but this is very variable.

increase

The deactivating groups (e.g., halogens) will increase/decrease the acidity of benzoic acid.

increase

electron donating groups tend to increase/decrease shielding and increase the required field strength for resonance

increase

for alkenes and alkanes, an increase on molecular weight will increase/decrease the boiling point

increase

hydrogen bonding will increase/decrease solubility in water and similar solvents (e.g., ethyl alcohol) for capable compounds.

increase

alcohols and alkanes boiling points increase/decrease with increasing molecular weight and increase/decrease with increased branching

increase, decreased

Electron-withdrawing substituents (e.g., nitro) on the carbon adjacent to the carboxyl in aliphatic acids, or on the benzene ring in aromatic compounds, will increase/decrease the acidity. while Electron-donating substituents (e.g., alkyl groups) will increase/decrease the acidity of acids.

increase,decrease

As Ho is increased, remember the rf required to bring about the flipping (point of resonance) increases/decreases.

increases

As one goes from left to right on the NMR spectrum, the energy required to cause the flip (absorbance) increases/decreases as the applied magnetic field increases

increases

for an SN1 reaction, As the stability of the intermediate carbocation increases/decreases, so does the rate of the reaction.

increases

n a mixture of compounds, two changes occur. The MP of a substance is depressed below its usual value, and the temperature range over which melting occurs increases/decreases. Each of these is asign of impurities

increases

MP increases as the molecular mass increases/decreases. why?

increases, This is due to dispersive forces

what bond is formed in an alpha helix aka whats the key feature

intraprotein hydrogen bonds formed between amino acids several positions from each other. The carbonyl oxygen and the amide -NH form the bonds

order from strongest to weakest 1. ion-ion 2. hydrogen bonding 3. dipole-dipole 4. dispersive

ion ion>hydrogen bonding>dipole dipole > dispersive *Hydrogen bonding involves oxygen, nitrogen, and fluorine. *A dipole requires an electronegative element (e.g., oxygen or a halide) bonded to carbon . Dipoles are polar molecules * These forces increase as the molecular size and asymmetry of the molecule increase.

A mneumonic for remembering the essential amino acids is what?

is VP Matt Hill (valine,phenylalanine,methionine,arginine,tryptophan,tyrosine,histidine,isoleucine,lysine and leucine).These tend to be some of the basic AAs, branched AAs, and heterocyclic AAs.

Chromatography?

is a separation and identification method utilizing a stationary phase that absorbs substances and a mobile phase that differentially dissolves and removes them from the stationary phase.

Ozonolysis (O3)?

is an important oxidation of double bonds. This reaction can localize the double bond. Each carbon of the double bond will end up as carbonyl, either a ketone or aldehyde. The original double bonded carbon was between these two carbons.

The Hoffman Rearrangement? what are the products

is the conversion of an amide into a primary amine in the presence of NaOH , Br2, and water. The product is the primary amine and carbon dioxide and HBr .

.Sublimation?

is the phase transition between the solid and gas phases

what is different about fractional distillation as opposed to normal distillation

it is simply a more precise method of distillation and in this method, vapor is run through glass beads allowing the compound with the higher boiling point to condense and fall back into solution

what does it mean to be aromatic?

it means the molecule is more stable and less reactive to electrophilic attack than corresponding double bonds. This stability is evident as the composite bond energies of the aromatic compound is less (more negative) than the corresponding bond energies of a similar nonaromatic compound.

how are alkenes synthesized?

it occurs via an elimination reaction and one or two functional groups are eliminated or removed to form a double bond ...dehydration of an alcohol is an E1 reaction where an alcohol forms an alkene in the presence of hot concentrated acid 1. in the first step, the acid protonates the hydroxyl group producing a good leaving group, water 2. in the next (slowest step, the water drops off forming aq carbocation 3. in the final yep, the a water molecule deprotonates the carbocation and an alkene is formed * the most stable product is the more substituted alkene

name the functional group R-CO-R'

ketone where R and R' may be same/different the O is double bonded (a carbonyl)

the witting reaction converts a ____ to an ______

ketone, alkene

Another important reaction is the oxidation of the double bond with (potassium permanganate) or (potassium dichromate). If the carbon is a secondary carbon, a _____ will result. If the carbon is primary, a ____ ____ will result

ketone, carboxylic acid

The naturally occurring amino acids are of the "d/l" series with the amino group to the left.

l series

the chemical shift of the methyl protons depends on the electronegativity of the substituent, with more electronegative substituents deshielding more and giving larger/smaller chemical shifts.

larger

in the hoffman elimination, the least/most stable alkene is the major product

least

The l ("el") series has the penultimate OH group on the right/left side.

left

Molecules with electron-withdrawing groups or double or multiple bonds are deshielded and found at chemical shifts away from TMS zero point, or to the left/right or upfield/downfield.

left, upfield

Aromatic double bonds are more/less susceptible to electrophilic attack than regular double bonds.

less

The more negative the enthalpy, the more/less stable the reacting alkene.

less

the longer the carbon chain, the more/less soluble the alcohol

less

amides are more/less basic than amines why?

less basic due to the electron withdrawing properties of the carbonyl

Paper chromatography polar components have a Rf factor (greater than/less than)

less than one since they dont travel as far as the non polar components because they are attracted to the polar paper

Recrystallization- The impurities (other substances in the mixture that are not desired) should have certain properties to allow adequate separation. The impurities should be more/less soluble in the solvent at higher/lower temperatures. The greater the concentration differences between the substance and the impurity, the better the separation. It's nearly impossible to separate two substances of nearly equal solubility and nearly equal concentrations in a sample.

less, higher

on carbonyl The two pairs of nonbonded electrons will react with Lewis acids/lewis bases or electrophiles/nucleophiles .

lewis acids, electrophiles

Organo lithium compounds are made from what 2 things

lithium metal and alkyl halides

Shielding occurs when electrons on the atom set up a magnetic field that opposes the Hoand decreases the effective field experienced by the nucleus. The field (Ho) being applied must then increase in order to reach the energy of the flipping transition of the nucleus (the point of resonance). So, the absorbance of that nucleus is more to the right. This occurs for nuclei that are attached to atoms with high/low electronegativity.

low

high/low temperatures and concentrated/dilute acid drive hydration towards the alcohol

low, dilute

8ppm corresponds to (high/low) magnetic field strength while 1ppm corresponds to (high/low) magnetic field q

low, high

Solvents for recrystallization should have certain properties. The desired substance should have low, not necessarily zero, solubility at high/low temperatures. There should be high solubility at higher/lower temperatures, and the graph of solubility versus temperature should be steep

low, higher

Electron withdrawing groups tend to (raise/lower) shielding thus decrease the magnetic field strength at which resonance takes place

lower

The unsaturated fatty acids have higher/lower melting points and may be liquids.

lower

nuclei aligned with the magnetic field have a (lower/higher) energy state than those aligned with the magnetic field

lower

the higher/lower the heat of hydrogenation, the more stable the alkene

lower

Acidic AAs will have higher/lower IPs because of the extra carboxyl group. Basic AAs will have higher/lower IPs because of the added basic groups.

lower, higher

NMR relies on the fact that a spinning nucleus generates a magnetic field because of its positive charge . In the absence of an externally applied magnetic field, the nuclei magnetic fields are randomly oriented. When an external magnetic field (Ho) is applied, each nucleus will either align with the field (lower/higher energy) or align in opposition to the field (lower/higher energy).

lower, higher

The freezing point (FP) is raised/lowered by the addition of solute to the solvent. FP is a colligative property

lowered

Grignard reagents are made from what 2 things?

magnesium metal and alkyl halides

There are four main types of spectroscopy used in the identification of organic compounds: 2._____ Spectroscopy This is used to determine the molecular mass and the chemical formula.

mass

for electrophoresis if the charges on the molecules are equal then the movement is inversely proportional to _____

mass

toluene is a benzene ring with ______ attached to the R position

methyl

list the order of reactivity from greatest to least for an SN2 reaction for these and why? methyl primary secondary tertiary

methyl >primary > secondary >tertiary because if the substrate is too substituted then the nucleophile can't get in there and attack

Any group which withdraws more electrons will make the amine more/less basic.

Substituted alkenes and trans vs cis alkenes tend to be more/less stable.

The beta isomer will have all groups in the equatorial positions and is more/less stable than the alpha isomer

alkenes are more/less acidic than alkanes

the enolate form is more/less reactive than the enol form.

what property must a nucleus have in order to undergo to register on nmr

must have an odd atomic or mass number so carbon 13 is the inly carbon isotope to register

the number of peaks due to splitting for a group of chemically equivalent hydrogens is given by the simple formula of ______

n+1 where n is the number of neighboring hydrogens that are not chemically equivalent

If the pH of the medium is greater than the pI, then the molecule will be negative/positive

negative

the oxygen on a carbonyl is very electronegative compared to the carbon and will carry a partial (positive/negative) charge The oxygen is able to accept and stabilize a positive/negative charge.

negative, negative

nitrobenzene is a benzene ring with ______ attached to the R position

nitrogen dioxide

The fatty acids are nonpolar/polar owing to the long hydrocarbon chain and are soluble/insoluble in water and polar solvents.

non polar, insoluble

the tail in a phospholipid is (polar/nonpolar) while the head is (polar/nonpolar)

non polar, polar

Neutral polar/nonpolar AAs (hydrophobic) shun water and tend to occupy the inside of proteins. Neutral polar/nonpolar AAs (hydrophilic) are attracted to water and tend to be on the surface of proteins

non polar,polar

does this describe an electrophile or a nucleophile a molecular species that is attracted to a positive charge (or partial positive charge). It may be negative or neutral, but will always have a free pair of electrons

nucleophile

for carbonyls, the partial positive charge on the carbon means that any attack on the carbonyl carbon will be from a (nucleophile/electrophile)

nucleophile

Organometallic compounds act like nucleophiles/electrophiles as the alkyl portion has a pair of electrons, and has relative negative charge.

nucleophiles: These compounds act like carbanions, resulting in nucleophilic attack on positive (electrophilic) atoms.

carboxylic acids and their derivatives prefer to undergo nucleophilic substitution/addition while aldehydes and ketones prefer to undergo nucleophilic substitution/addition

nucleophilic substitution, nucleophilic addition

aldehydes or ketones usually will act as a substate in nucleophilic/electrophilic addition or as a bronsted lowry acid/base by donating one of its alpha hydrogens

nucleophilic, acid

inorganic acids such as SOCl2, PCl3, PCl5 each react with carboxylic acids by electrophilic/nucleophilic substitution to form what

nucleophilic, acyl chlorides aka acid chlorides

alcohols react with carboxylic acids through nucleophilic/electrophilic substitution to form ______...what are the steps in the run

nucleophilic, esters 1. a strong acid catalyzes the reaction by protonating the hydroxyl group on the carboxylic acid

on carbonyl The two pairs of nonbonded electrons are electrophilic/ nucleophilic and can function as a nucleophile/electrophile or as a Lewis Base/lewis acid .

nucleophilic, nucleophile, lewis base

aldehydes and ketones typically undergo electrophilic/nucleophilic addition while other carbonyl carbons prefer electrophilic/nucleophilic substitution

nucleophilic, nucleophilic

whats the equation for specific rotation

observed rotation/ (path length (l*dm) * concentration (g/mL)

what is aldol condensation

occurs when one aldehyde reacts with another, when one ketone reacts with another, or when an aldehyde reacts with a ketone ...the reaction is catalyzed by an acid or base (is simply the combination of the nucleophilic addition to the carbonyl carbon and the electrophilic addition to the alpha carbon:

what happens to cause an azeotrope to be the product of distillation

occurs when the solution of two volatile liquids exhibits a positive deviation from raoults law and the solution will boil at a lower temperature than either pure compound *an azeotrope can also form when the solution has a higher boiling point than either pure substance

Paper chromatography non polar components have a Rf factor close to ____

one because they non polar components travel the furthest because they are not attracted to the polar paper so they travel almost as far as the solvent does

Organo copper compounds are made from what 2 things?

organo lithium compounds and copper(I) iodide (cuprous iodide):

Oxidation/reduction results in the addition of O2 while Oxidation/reduction results in the loss of O or O2

oxidation, reduction

Oxidation/reduction results in the addition of halogens while Oxidation/reduction results in the loss of a halogen

oxidation, reduction

Oxidation/reduction results in the loss of H2 while oxidation/reduction results in the addition of H2

oxidation, reduction

a simple way to think about oxidation for any compound is to consider the oxygen to hydrogen ratio of a molecule if this ratio increases, then the molecule has been (oxidized/reduced) and if the ratio decreases then the molecule has been (oxidized/reduced)

oxidized, reduced

generally speaking, oxidizing agents/reducing agents will have lots of oxygen while oxidizing agents/reducing agents will have lots of hydrogens

oxidizing agents, reducing agents

extraction is based upon what?

solubility due to similar polarities

specific rotation is inversely proportional to what?

path length (l) (dm) and concentration (g/mL)

when phosphoric acid forms what

phosphoric anhydrides

Carboxylic acids are nonpolar/polar.

polar

If the pH of the medium is less than the pI, then the molecule will be negative/positive .

positive

The parent peak on the MS graph is the parent molecule with a positive/negative charge. Because of isotopes , there may still be smaller peaks to the right of the parent peak. The parent peak is not necessarily the tallest peak (called the base peak, or peak of greatest intensity, and is given a value of 1.0 or 100% for comparison with other peaks).

positive

when nitrogen takes 4 bonds it has a negative/positive charge

positive

Primary/secondary/tertiary means there is one carbon group (R) attached to the carbon containing the functional group.

primary

Ammonia forms what by reacting with alkyl halides

primary amines

In an NMR spectrum, the area under the peak represents what?

proportional to the number of hydrogens represented by that peak so the more chemically equivalent hydrogens, the greater the area

tautomerization involves a _____shift in this case from an alpha carbon position to the ______ oxygen position

proton, carbonyl

what happens in a wolff kishner reduction?

reduces a ketone or aldehyde by removing the oxygen and replacing it with 2 hydrogens

A reducing/oxidizing sugar must have the anomeric carbon free.

reducing *The glycosidic bond ties up the anomeric carbon so it cannot react. This means the polymers, like cellulose or starch, are not reducing.

The natural sugars are the "d" series. and have the penultimate OH group on the right/left side.

right

The parent peak on an MS graph is always the larger peak farthest to the right/left

right (Any small peaks to the right of P would represent minor isotopes.)

Molecules with high electron density around hydrogens would result in shielding and be found near TMS zero point, to the left/right or upfield/downfield.

right, upfield

unsaturated/Saturated fatty acids have no double bonds. Unsaturated/saturated fatty acids have one or more double bonds.

saturated, unsaturated

Primary/secondary/tertiary means two carbon groups (R) are attached to the carbon containing the functional group.

secondary

primary amines form what by reacting with alkyl halides

secondary amines,

amine basicity from highest basicity to lowest basicity when the functional groups are electron donating 1primary 2 secondary 3. ammonia

secondary>primary>ammonia

in a combustion reaction, whats the equation for the number of "n" Co2 produced

simply "n"

distillation The extent of separation of L and H will be better when: 1. the rate of heating is (fast/slow) 2. the differences in boiling points of the liquids are big/small 3. the impurity liquid is present in small amounts

slow, big- widely separated

Recrystallization is distinguished from precipitation in two ways. First, recrystallization is much slower/faster than precipitation, occurring over hours to days versus seconds to minutes. Second, precipitation results in increased/decreased impurities being in the solid phase with the desired substance.

slower, increased

The melting of a solid should occur over a very large/small temperature range if the solid is pure.

small

The stronger the intermolecular forces, the smaller/larger the vapor pressure and the lower/higher the temperature must be for the liquid to boil.

smaller, higher

NaBH4 (sodium borohydride) only converts the acid to a ____ ____

sodium salt.

The observed rotation, is directly proportional to what?

specific rotation

carboxylic acids are very weak/strong so when a proton is removed, the conjugate base is stabilized by resonance

strong *electron withdrawing groups on the alpha carbon help to further stabilize the conjugate base and thus increasing the acidity of the corresponding carboxylic acid

The ammonium salt of aniline is then a weaker/stronger acid and has a lower pKa than the salt of methyl amine.

stronger

a sigma bond is (stronger/weaker) than a pi bond

stronger

benzene undergoes substitution or addition? why?

substitution *if a functional group were added to benzene then it would disrupt resonance and the compound would no longer be aromatic

The main reaction type of aromatic compounds is electrophilic substitution/elimination:

substitution Substitution is preferred over electrophilic addition, as for a regular double bond, because of the great stability of maintaining the aromatic ring.

Primary/secondary/tertiary means three carbon groups (R) are attached to the carbon containing the functional group.

tertiary

secondary amines form what by reacting with alkyl halides

tertiary amines,

list the order of reactivity from greatest to least for an SN1 reaction for these and why? methyl primary secondary tertiary

tertiary>secondary>primary>methyl because the SN1 reaction is a 2 step process and depends on the stability of the carbocation and the more substituted the carbocation is, the more stable it is so tertiary is the most stable

A standard is used to set a zero point on the chemical shift scale because it is relative. This substance is _____ _____ , which has __ equivalent hydrogens (as the methyl groups) and ____ equivalent carbons (as the methyls). The absorption of TMS is set to zero.

tetramethyl silane (TMS), 12, 4

The double bond is made of two bonds, which are what?

the sigma bond and the pi bond

For benzene ring with one substituent, meta means that a hydrogen is attached where?

to the right and left of the ortho hydrogens

For benzene ring with one substituent at the top peak of the ring, ortho means that a hydrogen is attached where?

to the right and left of the substituent

what is transesterifiction

trading alkoxy groups on an ester

If the bonds are cis/trans, the molecule is straight and not kinked. If the bonds are cis/trans, the molecule is nonlinear (or kinked)

trans, cis

true/false All amino acids are solids.

true

true/false At pHs below an IP, the AA will be positive (protonated on the amino group). At pHs above the IP, the AA will be deprotonated (the acid will lose its hydrogen).

true

true/false At the MP, the heat is used to break all the intermolecular noncovalent forces in the case of sublimation; only some of the forces are used in the case of melting.

true

true/false Electrophilic addition results in the loss of the aromaticity of the ring. For this reason, aromatic rings rarely undergo electrophilic additions.

true

true/false The amide nitrogen is considered neither basic nor nucleophilic, in contrast to the amine, which is both.

true

true/false The stationary phase is usually polar and absorbs polar molecules more firmly than nonpolar ones. The solvents are usually more nonpolar or involve a series of nonpolar to polar solvents in sequence. This means the first molecules off the column or near the top of the plate (in TLC) are more nonpolar. Nonpolar molecules move through the system faster. Polar molecules are retained longer and appear last. Solvent selection is based on solvent polarity and expected solubilities of the substances in the mixture.

true

true/false amides can behave as weak acids or weak bases

true

true/false an acid halide may be converted into any of the other derivatives, an ester into an amide but not an amide into an ester or an ester into an acid halide

true

true/false for halogenation of ketones when a base is used it is difficult to prevent halogenation at more than one of the alpha positions

true

true/false: a substance is not pure as long as its MP is less than its standard MP and/or the MP occurs over a range and not at a point.

true

true/false? During the phase transition, little of the heat energy is being used to raise the temperature, because it is being used to overcome intermolecular forces; so the temperature of the substance remains relatively constant as the phase transition occurs.

true

true/false: Conjugated double bonds and aromatic systems strongly absorb in the UV range.

true: The greater the conjugation (including aromatics), the easier the excitation, and the lower the energy required (i.e., the longer the wavelength and the lower the frequency ). Highly conjugated double bonds will absorb in the visible range

Maltose is made with ____ and ____ in an _____ bond

two glucoses in an alpha-1,4 bond

When an alkene undergoes addition, what occurs?

two groups add to the carbon atoms of the double bond and the carbons become saturated.

Thin-layer chromatography (TLC)

uses a solid, again silica or alumina commonly, spread thinly on a glass or other support. One end of the plate is set in a solvent tray and as the solvent "marches" up the plate by a type of capillary action, the different substances (molecules) move differentially with the solvent and separate. The ratio of the distance a molecule travels up the plate to the solvent front is called the Rf (ratio to the front) and is specific for any solid phase, solvent, and molecule. Because the least polar molecules will travel the farthest up the plate, they will have the higher values of Rf.

Column chromatography

uses a stationary phase of a solid such as alumina or silica gel (both of which are polar). Then, the liquid phase is a sequence of solvents that elutes the substance from the solid phase. The sequence of solvents is generally from the least polar to the most polar.The substances are first absorbed into the solid phase. Then, as the solvent passes through the column, the substances (molecules) dissolve into it and pass down the column with the solvent. Since the more polar molecules are held the tightest by the alumina or silica gels (the molecules do not react with the gel but are bound by noncovalent bonding ), the first molecules out of the column are the most nonpolar , or least polar . The last molecules to come off the column are the most polar molecules.

Gas chromatography (GC)

utilizes a liquid stationary phase and a gas mobile phase to affect the separation. The idea is still the same. The most tightly bound substances (the most polar) will be the last to come out of the chamber in the gas stream.

distillation is separation based upon what?

vapor pressure

The boiling point (BP) of a liquid is the temperature at which its _____ equals the ____

vapor pressure (VP), external pressure (or applied pressure).

A MP is the temperature at which the _____ equals the _____

vapor pressure of the solid , vapor pressure of the liquid

The boiling point of a mixture of liquids occurs when the external pressures equal the sum of what?

vapor pressures of the components of the mixture

what does the infared spectrum detect

vibrations, bending, stretching, and related motions of the bonds in molecules.

When the glycosidic bond is formed, a_____ is produced

water

to make a carboxylic acid, _____is used.

water

Nitriles are converted into amides by ____ ______

water hydrolysis

hydration takes place when _______ is added to an ______ in the presence of an ______

water is added to an alkene in the presence of acid

the weaker/stronger the base, the better the leaving group

weaker

aromatic amines (amines attached directly to benzene ring) are much weaker/stronger bases than non aromatic amines why?

weaker bases bc the electron pair can delocalize around the benzene ring ...substituents that withdraw electrons from the benzene ring will further weaken the aromatic amine

Aniline is a weaker/stronger base than methyl amine because the benzene ring withdraws electrons.

weaker because bases want to donate electrons so if there is a group like benzene withdrawing electrons from it then it cannot share its electrons as well so its basicity decreases

what does markovnikov's rule state

when hydrogen halides are added to alkenes they follow M's rule which states that hydrogen will add to the least substituted carbon of the double bond

whats a conjugated double bond

when two or more double bonds are in sequence, separated by a single bond.

what type of bonding/forces exists in quaternary structure

when two or more separate proteins non covalently bonded together by hydrogen and other non covalent forces

the triple bond is made of three bonds which are what?

which has two pi bonds and one sigma bond,

Ultraviolet Spectroscopy: Double bonds, even isolated ones, will/will not weakly absorb UV radiation as electrons are excited.

will

Voir tous les ensembles d'études

Organic Chemistry Set

Ensembles d'études connexes

APHG Midterms review (Units 1, 2, 3)

Unit 3 Exam

Topic 13

Topik reading question 5

Quiz 8

Ch 11 - Exercise

Practice Quiz #11 PowerPoint Chapter 1

Organizational Behavior Final

Chapter 5: Government's Role and Government Failure, Chapter 5 Government's Role and Government Failure, ch5 test

ELM 124 Final Exam Study

Marketing 304 Quiz 1, Marketing Management Chapter 1

Government Unit 1 International Governments

FireFighter 1 Final

Black Board Blood Bank Question

Pagkamamamayan

ingenuity

Med surg 2 Final Review

lab 1 exam

Remediation for Med-Surg

MNG 590