Q: Which of the following represents the correct ranking in terms of increasing boiling point? A) n-butane < 1-butanol < diethyl ether < 2-butanone B) n-butane < 2-butanone < diethyl ether < 1-butanol C) 2-butanone < n-butane < diethyl ether < 1-butanol D) n-butane < diethyl ether < 1-butanol < 2-butanone E) n-butane < diethyl ether < 2-butanone < 1-butanol

n-butane < diethyl ether < 2-butanone < 1-butanol

Q: When a carbonyl is part of a conjugated ?-network, the C=O stretch: A) has a higher frequency than in a nonconjugated system. B) has a lower frequency than in a nonconjugated system. C) always occurs at 1710 cm-1. D) occurs around 2700 cm-1. E) cannot be distinguished from the C=O stretch in a nonconjugated system.

has a lower frequency than in a nonconjugated system.

Question 1

Which of the following correctly describes the bond angle and hybridizations present in formaldehyde?  A) C, sp2; O, sp3; HCO, ~120Â°  B) C, sp2; O, sp2; HCO, ~120Â°  C) C, sp2; O, sp2; HCO, ~109.5Â°  D) C, sp3; O, sp2; HCO, ~109.5Â°  E) C, sp3; O, sp3; HCO, ~109.5Â°

Accepted Answer

C, sp2; O, sp2; HCO, ~120Â°

Question 2

The double bond between carbon and oxygen is similar to an alkene C=C, except that C=O is:  A) shorter and weaker.  B) shorter and stronger.  C) longer and weaker.  D) longer and stronger.  E) longer.

Accepted Answer

shorter and stronger

Question 3

The positively polarized carbon atom of a carbonyl group acts as:  A) an electrophile and a Lewis base.  B) a nucleophile and a Lewis base.  C) an electrophile and a Lewis acid.  D) a nucleophile and a Lewis acid.  E) both a Lewis acid and a Lewis base.

Accepted Answer

an electrophile and a Lewis acid.

Question 4

Another name for ?-methoxybutyraldehyde is:  A) 2-methoxypropanal.  B) 3-methoxypropanal.  C) 2-methoxybutanal.  D) 3-methoxybutanal.  E) 2-methoxypentanal.

Accepted Answer

3-methoxybutanal

Question 5

Which of the following represents the correct ranking in terms of increasing boiling point?  A) n-butane < 1-butanol < diethyl ether < 2-butanone  B) n-butane < 2-butanone < diethyl ether < 1-butanol  C) 2-butanone < n-butane < diethyl ether < 1-butanol  D) n-butane < diethyl ether < 1-butanol < 2-butanone  E) n-butane < diethyl ether < 2-butanone < 1-butanol

Accepted Answer

n-butane < diethyl ether < 2-butanone < 1-butanol

Question 6

Which of the following compounds is most soluble in water?  A) acetone  B) cyclohexanone  C) 2-butanone  D) 3-butanone  E) benzophenone

Accepted Answer

acetone

Question 7

In carbon NMR, the carbon atom of the carbonyl group in aldehydes and ketones has a chemical shift of about:  A) 20 ppm.  B) 40 ppm.  C) 60 ppm.  D) 120 ppm.  E) 200 ppm.

Accepted Answer

200 ppm

Question 8

Which compound will show an intense peak in the mass spectrum at m/z 58?  A) CH3COCH2CH2CH3  B) (CH3)2CHCOCH3  C) CH3CH2COCH2CH3  D) (CH3)3CCHO  E) (CH3)3CCOCH3

Accepted Answer

CH3COCH2CH2CH3

Question 9

In the mass spectrum of 3,3-dimethyl-2-butanone, the base peak will occur at m/z:  A) 43  B) 58  C) 84  D) 85  E) 100

Accepted Answer

43

Question 10

When a carbonyl is part of a conjugated ?-network, the C=O stretch:  A) has a higher frequency than in a nonconjugated system.  B) has a lower frequency than in a nonconjugated system.  C) always occurs at 1710 cm-1.  D) occurs around 2700 cm-1.  E) cannot be distinguished from the C=O stretch in a nonconjugated system.

Accepted Answer

has a lower frequency than in a nonconjugated system.

Question 11

In the proton NMR spectra of aldehydes and ketones, the protons bonded to carbons adjacent to the carbonyl group typically fall into which of the chemical shift ranges below?  A) 1.0-2.0 ppm  B) 2.0-3.0 ppm  C) 4.0-4.5 ppm  D) 7.0-8.0 ppm  E) 9.0-10.0 ppm

Accepted Answer

2.0-3.0 ppm

Question 12

The proton NMR spectrum of an unknown compound contains a triplet at 9.8 ppm. Which of the following could be this unknown?  A) (CH3)3CCHO  B) CH3CH2CH2CO2H  C) CH3CH2CH2CHO  D) CH3CO CH2Ph  E) PhCHO

Accepted Answer

CH3CH2CH2CHO

Question 13

Which of the following compounds would show only one triplet in its off resonance decoupled 13C NMR spectrum?  A) acetone  B) butanal  C) pentanal  D) 2-pentanone  E) 3-pentanone

Accepted Answer

3-pentanone

Question 14

Which of the following transitions is usually observed in the UV spectra of ketones?  A) n to ?*  B) n to ?  C) ? to n  D) ? to ?*  E) n to ?*

Accepted Answer

n to ?*

Question 15

The strongest absorptions in the UV spectra of aldehydes and ketones are ones which result from __________ electronic transitions.  A) ? to ?*  B) ? to ?*  C) n to ?*  D) ? to ?*  E) ? to ?*

Accepted Answer

? to ?*

Question 16

What name is given to the linear polymer which contains many formaldehyde units?  A) trioxane  B) formalin  C) paraformaldehyde  D) polyacetaldehyde  E) polyalal

Accepted Answer

paraformaldehyde

Question 17

What reagent can be used to convert 2-methylbutan-1-ol into 2-methylbutanal?  A) LiAlH4  B) Na2Cr2O7  C) O3  D) KMnO4  E) PCC

Accepted Answer

LiAlH4

Question 18

What reagents can be used to convert 1-hexyne into 2-hexanone?  A) 1. Sia2BH; 2. H2O2, NaOH  B) Hg2+, H2SO4, H2O  C) 1. O3; 2. (CH3)2S  D) 1. CH3MgBr; 2. CO2  E) 1. H2, Ni; 2. Na2Cr2O7, H2SO4

Accepted Answer

Hg2+, H2SO4, H2O

Question 19

Oxidation of a 1Â° alcohol with chromic acid results in the production of __________.  A) an ester  B) a ketone  C) an aldehyde  D) an ether  E) none of the above

Accepted Answer

none of the above

Question 20

Oxidation of a 2Â° alcohol with chromic acid results in the production of __________.  A) an ester  B) a ketone  C) an aldehyde  D) an ether  E) none of the above

Accepted Answer

a ketone

Question 21

Oxidation of a 3Â° alcohol with chromic acid results in the production of __________.  A) an ester  B) a ketone  C) an aldehyde  D) an ether  E) none of the above

Accepted Answer

none of the above

Question 22

Oxidation of a 1Â° alcohol with pyridinium chlorochromate results in the production of __________.  A) an ester  B) a ketone  C) an aldehyde  D) an ether  E) none of the above

Accepted Answer

an aldehyde

Question 23

Which of the following carbonyl compounds may be made from 1,3-dithiane?  1) methyl vinyl ketone   2) 2-pentanone   3) 3,3-dimethyl-2-butanone   4) 2-phenylethanal  A) 1 & 4  B) 2 only  C) 2 & 3  D) 2 & 4

Accepted Answer

2 & 4

Question 24

Treatment of a nitrile with a Grignard reagent followed by hydrolysis results in __________.  A) an ester  B) a ketone  C) an aldehyde  D) an ether  E) an alcohol

Accepted Answer

a ketone

Question 25

Which of the following describes a synthesis of an aldehyde?  A) hydrogenation of an acid chloride using Pd/BaSO4/S as a poisoned catalyst  B) reaction of a primary alcohol with Na2Cr2O7  C) reaction of a ketone with ozone  D) treatment of an alkene with Sia2BH  E) none of the above

Accepted Answer

hydrogenation of an acid chloride using Pd/BaSO4/S as a poisoned catalyst

Question 26

Which series of reactions described below, if any, will result in the formation of 2-methylpentan-3-one starting with 1-propanol?   A) 1. (CH3)2CHMgBr/ diethyl ether   2. dilute H3O+   3. PCC  B) 1. Na2Cr2O7/H2SO4 and heat   2. SOCl2   3. 2 (CH3)2CHMgBr/ diethly ether   4. H3O+  C) 1. Na2Cr2O7/H2SO4 and heat   2. (CH3)2CHMgBr/ diethyl ether   3. dilute H3O+   4. LiAlH4  D) 1. PCC   2. (CH3)2CHLi/ diethyl ether   3. dilute H3O+   4. Na2Cr2O7/H2SO4 and heat  E) none of the above

Accepted Answer

1. PCC  2. (CH3)2CHLi/ diethyl ether  3. dilute H3O+  4. Na2Cr2O7/H2SO4 and heat

Question 27

When the carbonyl group of a neutral ketone is protonated,:  A) the resulting species becomes more electrophilic.  B) the resulting species is activated toward nucleophilic attack.  C) subsequent nucleophilic attack on the resulting species is said to occur under acid-catalyzed conditions.  D) the resulting species has a positive charge.  E) all of the above.

Accepted Answer

all of the above.

Question 28

Consider the equilbrium of each of the carbonyl compounds with HCN to produce cyanohydrins. Which is the correct ranking of compounds in order of increasing Keq for this equilbrium?  A) H2CO < cyclohexanone < CH3CHO < 2-methylcyclohexanone  B) CH3CHO < 2-methylcyclohexanone < cyclohexanone < H2CO   C) cyclohexanone < 2-methylcyclohexanone < H2CO < CH3CHO   D) cyclohexanone < 2-methylcyclohexanone < CH3CHO < H2CO   E) 2-methylcyclohexanone < cyclohexanone < CH3CHO < H2CO

Accepted Answer

2-methylcyclohexanone < cyclohexanone < CH3CHO < H2CO

Question 29

) Rank the following compounds in order of their propensity to become a hydrate in water (ie, start with the least easy to hydrate: CH3COCH2CH3, H2CO, Cl3CCHO, and CH3CH2CHO.  A) CH3CH2CHO < CH3COCH2CH3 < H2CO < Cl3CCHO  B) CH3CH2CHO < H2CO < CH3COCH2CH3 < Cl3CCHO  C) CH3COCH2CH3 < H2CO < CH3CH2CHO < Cl3CCHO  D) CH3COCH2CH3 < CH3CH2CHO < H2CO < Cl3CCHO

Accepted Answer

CH3COCH2CH3 < CH3CH2CHO < H2CO < Cl3CCHO

Question 30

An ylide is a molecule that can be described as a:  A) carbanion bound to a negatively charged heteroatom.  B) carbocation bound to a positively charged heteroatom.  C) carbocation bound to a carbon radical.  D) carbocation bound to a diazonium ion.  E) carbanion bound to a positively charged heteroatom.

Accepted Answer

carbanion bound to a positively charged heteroatom.

Question 31

Which of the following is also known as a Schiff base?  A) an imine  B) a cyanohydrin  C) a hydrate  D) sodium hydroxide  E) an aldehyde

Accepted Answer

an imine

Question 32

Acetals will react with:  A) H3O?  B) NaOCH3  C) PhLi  D) CH3CH2MgBr  E) NaBH4

Accepted Answer

H3O?

Question 33

Why do acetal-forming reactions that use ethylene glycol have more favorable equilbrium constants than those using methanol?  A) Ethylene glycol reacts more rapidly.  B) They are more favorable on entropy grounds.  C) They are more favorable on enthalpy grounds.  D) Ethylene glycol is acidic and catalyzes the reaction.  E) The ethylene acetal can serve as a protecting group.

Accepted Answer

They are more favorable on entropy grounds.

Question 34

What intermediate occurs when a ketone undergoes a Wolff-Kishner reduction?  A) a cyanohydrin  B) a hydrated aldehyde  C) a carboxylate  D) a semicarbazone  E) a hydrazone

Accepted Answer

a hydrazone

Question 35

The reagent which converts a carbonyl group of a ketone into a methylene group is:  A) Na, NH3, CH3CH2OH  B) LiAlH4  C) NaBH4, CH3CH2OH  D) Zn(Hg), conc. HCl  E) LiAlH[OC(CH3)3]3

Accepted Answer

Zn(Hg), conc. HCl

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