Deck 9: Aldehydes and Ketones

Question 1

Which of the hydrogens in the following molecule are most acidic? The hydrogens on carbon

A) 1
B) 2
C) 3
D) 4
E) 5

Answer 1

2

Question 2

What is the structure of cyclohexanecarbaldehyde?

A)
B)
C)
D)
E)

Answer 2

Question 3

The enol tautomer of 3-pentanone is:

A)
B)
C)
D)
E)

Answer 3

Question 4

What class of compound most closely resembles an acetal in its reactivity with CH₃MgBr?

A) ethers
B) aldehydes
C) ketones
D) alcohols
E) thiols

Question 5

Which of the following compounds is a cyanohydrin?

A)
B)
C)
D)
E)

Question 6

Which of the following compounds is a hemiacetal?

A)
B)
C)
D)
E)

Question 7

The number of a-hydrogens in is:

A) 1
B) 3
C) 4
D) 8
E) 14

Question 8

Which of the following molecules is a hemiacetal?

A)
B)
C)
D)
E)

Question 9

Which of the following aldehydes can exist in equilibrium with a cyclic hemiacetal?

A) 4-pentenal
B) 3-hydroxypropanal
C) 2-hydroxybutanal
D) 3-hydroxybutanal
E) 4-hydroxybutanal

Question 10

The equilibrium that exists between the keto and enol forms of aldehydes and ketones is known as:

A) stereoisomerism
B) configurational isomerism
C) geometric isomerism
D) tautomerism
E) positional isomerism

Question 11

The name of the following is:

A) 2-hydroxy-4-pentanone.
B) 2-oxo-4-pentanol.
C) 4-oxo-2-pentanol.
D) 1-acetyl-2-propanol.
E) 4-hydroxy-2-pentanone.

Question 12

The expected order of boiling points of the following is:

A) 3>2>1
B) 2>1>3
C) 2>3>1
D) 1>2>3
E) 1>3>2

Question 13

The predominant product from the reaction below is:

A)
B)
C)
D)
E)

Question 14

The IUPAC name for ethyl methyl ketone is

A) 2-butanone
B) 2-pentanone
C) 3-pentanone
D) propanone
E) acetophenone

Question 15

Which of the following molecules has the highest boiling point?

A) o-xylene
B) m-xylene
C) p-xylene
D) benzaldehyde
E) benzyl alcohol

Question 16

The IUPAC name for the following molecule is:

A) 3-ethyl-1-phenyl-3-pentenone
B) 3-ethyl-5-phenyl-2-penten-4-one
C) allyl benzyl ketone
D) (E)-3-ethyl-1-phenyl-3-penten-2-one
E) (Z)-3-ethyl-1-phenyl-3-penten-2-one

Question 17

What is the class of compound produced from the reaction of a ketone with hydrazine?

A) oxime
B) amide
C) hydrazone
D) semicarbazone
E) imide

Question 18

The common name for the following molecule is:

A) acetaldehyde
B) dimethyl aldehyde
C) ethyl ketone
D) formaldehyde
E) methylmethanal

Question 19

Which of the following is a hydrazone?

A)
B)
C)
D)
E)

Question 20

In a carbonyl group

A) the oxygen acts as a Lewis acid.
B) the C=O bond length is shortened due to resonance.
C) the carbon is sp³ hybridized.
D) the carbon is nucleophilic and the oxygen is electrophilic.
E) the carbon is electrophilic and the oxygen is nucleophilic.

Question 21

What type of compound is produced from the following reaction?

A) an amide
B) an alcohol
C) an acid
D) an aldehyde
E) a ketone

Question 22

Which of the following nucleophiles add reversibly to a carbonyl group?

A) I, II and IV
B) II
C) I and II
D) III and IV
E) I, II, III and IV

Question 23

Which hydrogens in the following compound will be exchanged most rapidly for deuterium upon reaction with D₂O and NaOD?

A) H₁
B) H₂
C) H₃
D) H₄
E) H₅

Question 24

In the mechanism for acid catalyzed hemiacetal formation, the first step is:

A) protonation of the carbonyl oxygen
B) nucleophilic attack at the carbonyl carbon
C) protonation of the oxygen of the alcohol
D) nucleophilic attack at the carbon of the alcohol
E) elimination of a water molecule

Question 25

Which of the following compounds will not act as a nucleophile in an Aldol reaction?

A)
B)
C)
D) HCHO
E) C and D

Question 26

What statement is false relative to the nucleophilic additions?

A) When a weak nucleophile is present, the reaction can be catalyzed by acid.
B) The nucleophile attacks the trigonal carbon of the carbonyl group.
C) Ketones are more reactive than aldehydes.
D) Nucleophiles that add irreversibly are poor leaving groups.
E) Nucleophiles can be classified as those that add reversibly to carbonyl compounds and those that add irreversibly.

Question 27

Which statement about the mechanism of imine formation from a primary amine and an aldehyde or ketone is false?

A) The first steps involve addition of the amine to the carbonyl carbon to form a tetrahedral intermediate.
B) The last steps involve elimination of water to form a carbon-nitrogen p-bond.
C) All steps are reversible.
D) The reaction involves S_N2 displacement of the carbonyl oxygen by the amine nitrogen.
E) The reaction does not require a strong acid catalyst.

Question 28

Which of the following reactions will produce a cyanohydrin?

A)
B)
C)
D)
E)

Question 29

The products from are:

A)
B)
C)
D)
E) no reaction

Question 30

Which of the following compounds will give a positive silver mirror test (Tollens' test)?

A)
B)
C)
D)
E)

Question 31

What is the structure of the aldol produced from reacting propanone with NaOH?

A)
B)
C)
D)
E)

Question 32

The second step in the base catalyzed aldol condensation is:

A) formation of the enolate ion
B) addition of an enolate to a carbonyl group
C) protonation of the alkoxide ion
D) protonation of the carbonyl oxygen
E) loss of a proton from the $\alpha$ carbon

Question 33

Which reagent will accomplish the following transformation?

A) NaOH
B) CrO₃, H₂SO₄
C) CH₃MgBr
D) NaBH₄
E) H₂, Pd

Question 34

What reaction will produce the following product?

A)
B)
C)
D)
E)

Question 35

What Grignard reagent and carbonyl compound react to give benzyl alcohol after treatment with aqueous acid?

A) phenyl magnesium bromide and formaldehyde
B) phenyl magnesium bromide and oxirane
C) benzaldehyde and methyl magnesium bromide
D) benzaldehyde and ethyl magnesium chloride
E) acetophenone and methyl magnesium chloride

Question 36

Which reagents would you use to accomplish the following conversion?

A) NaBH₄, H₂O
B) LiAlH₄, ether; then H₃O⁺
C) H₂, Pt
D) all of these
E) none of these

Question 37

An oxime can be produced by the reaction of an aldehyde and:

A) hydroxylamine
B) hydrazine
C) methylamine
D) phenylhydrazine
E) semicarbazide

Question 38

The product from is:

A)
B)
C)
D)
E)

Question 39

The reaction of a Grignard reagent with acetone followed by acid hydrolysis will produce what type of product?

A) a primary alcohol
B) a secondary alcohol
C) a tertiary alcohol
D) a carboxylic acid
E) a ketone

Question 40

What reactants give the following molecule upon acid hydrolysis?

A) cyclohexyl magnesium bromide and acetaldehyde
B) cyclohexanol and
C) cyclohexanone and
D) cyclohexanecarbaldehyde and
E) cyclohexanone and ethenyl magnesium bromide

Question 41

The aldol obtained by treating with base is:

A)
B)
C)
D)
E)

Question 42

The organic product of the reaction is:

A)
B)
C)
D)
E)

Question 43

How many hydrogens in the following compound will be exchanged for deuterium upon reaction with D₂O and an acid catalyst?

A) 0
B) 2
C) 4
D) 5
E) 8

Question 44

The major product obtained from is:

A)
B)
C)
D)
E)

Question 45

Which reagent can be used to accomplish the following transformation?

A) pyridinium chlorochromate
B) Tollens' reagent
C) NaBH₄
D) H₂, Ni
E) NaH