Free Practice Quiz Question List

09 Aldehydes and Ketones Online Quiz Questions

Use this free practice quiz with 20 questions to review 09 Aldehydes and Ketones, test your knowledge, and prepare for your next test or exam.

20 questions

Written response

1 point

What suffix is commonly used when an aldehyde group is attached to a ring?

Choose one

1 point

A carbonyl carbon is bonded to one hydrogen and one carbon group. Is the compound an aldehyde or a ketone?

A
An aldehyde, because the carbonyl carbon is bonded to a hydrogen.
B
A ketone, because the carbonyl carbon is bonded to two carbon groups.
C
A ketone, because its carbonyl carbon is bonded to a hydrogen.
D
An aldehyde, because its carbonyl carbon is bonded to two carbon groups.

True or false

1 point

True or false: In a ketone, the carbonyl carbon is bonded to two carbon groups.

A
True
B
False

True or false

1 point

True or false: During nucleophilic addition to a carbonyl, the carbonyl carbon changes from trigonal planar to tetrahedral.

A
True
B
False

Fill in the blank

1 point

During nucleophilic addition, the nucleophile bonds to the carbonyl carbon as the C=O π electrons shift onto , producing an intermediate.

Written response

1 point

In a polarized carbonyl group, which atom is the electrophilic site attacked by a nucleophile?

Choose one

1 point

Under acidic conditions, what is the effect of protonating a carbonyl oxygen before water attacks?

A
It makes the carbonyl carbon less electrophilic, so water cannot attack.
B
It increases the electrophilicity of the carbonyl carbon, allowing water to attack.
C
It converts water into a hydride donor.
D
It causes the carbonyl carbon to become a leaving group.

Choose all

1 point

Select all reasons aldehydes generally undergo nucleophilic addition more readily than ketones.

A
The extra carbon substituent in a ketone crowds the site of nucleophilic attack.
B
A ketone's extra carbon substituent makes its carbonyl carbon more electrophilic.
C
The extra carbon substituent donates electron density toward the carbonyl carbon.
D
Aldehydes have two carbon substituents, while ketones have one.

Fill in the blank

1 point

Hydride reduction of an aldehyde produces a alcohol, whereas hydride reduction of a ketone produces a alcohol.

Choose one

1 point

Which statement correctly compares sodium borohydride (NaBH₄) and lithium aluminum hydride (LiAlH₄) in carbonyl reduction?

A
NaBH₄ is more reactive than LiAlH₄ and is incompatible with water.
B
Both reagents require water to be present during hydride addition.
C
LiAlH₄ is more reactive than NaBH₄ and is incompatible with water.
D
Only LiAlH₄ reduces aldehydes and ketones.

Choose all

1 point

Select all statements about hydride reagents and carbonyl reduction that are supported.

A
NaBH₄ is a common, comparatively mild reagent for reducing aldehydes and ketones.
B
LiAlH₄ reduces aldehydes and ketones and is more reactive than NaBH₄.
C
LiAlH₄ is compatible with water during hydride addition.
D
With LiAlH₄, the product is protonated in a separate work-up step.

Choose one

1 point

A ketone reduction creates a new stereogenic center, and its two carbonyl faces are equally accessible in an achiral environment. Which outcome is possible?

A
Only one enantiomer forms because the carbonyl is planar.
B
Both enantiomers may form if the two faces are equally accessible in an achiral environment.
C
A pair of diastereomers must form in every ketone reduction.
D
No stereogenic center can form during ketone reduction.

Open ended

1 point

Describe the usual steps of nucleophilic addition to an aldehyde or ketone and explain why it is classified as addition rather than substitution.

Choose one

1 point

Why is the usual reaction of a nucleophile with an aldehyde or ketone classified as addition rather than substitution?

A
It is addition: the nucleophile bonds to the carbonyl carbon and the C=O π bond becomes a C–O single bond.
B
It is substitution: the nucleophile replaces a suitable leaving group attached to the carbonyl carbon.
C
It is elimination: the carbonyl carbon loses both carbon substituents.
D
It is oxidation: the oxygen leaves as a water molecule.

Written response

1 point

What suffix is commonly used when an aldehyde group is attached to a ring? Enter the suffix, including its hyphen.

Written response

1 point

What class of alcohol forms when an aldehyde is reduced with a hydride donor and then protonated? Enter the alcohol class.

True or false

1 point

True or false: The structure $\mathrm{R{-}CO{-}R'}$ , where $\mathrm{R}$ and $\mathrm{R'}$ are carbon groups, represents an aldehyde.

A
True
B
False

Choose one

1 point

You need a common, comparatively mild hydride reagent to reduce a ketone. Which choice best fits that description?

A
Sodium borohydride ( $\mathrm{NaBH_4}$ )
B
Lithium aluminum hydride ( $\mathrm{LiAlH_4}$ )
C
Water ( $\mathrm{H_2O}$ )
D
A proton donor alone

Choose one

1 point

In a polarized carbonyl group, which atom is identified as a site for electrophiles?

A
The carbonyl carbon, because it is partially positive
B
The carbonyl oxygen, because it is partially negative
C
Either atom, because the bond is unpolarized
D
Neither atom, because the carbonyl is planar

Choose one

1 point

A nucleophile is added to either an aldehyde or a ketone under comparable conditions. Which explanation best accounts for aldehydes generally reacting more readily?

A
Ketones are more reactive because two carbon substituents make the carbonyl carbon more electrophilic.
B
Aldehydes are more reactive only because their carbonyl groups are nonplanar.
C
Aldehydes are generally more reactive because ketones have an extra substituent that crowds the attack site and donates electron density.
D
They have equal reactivity because both contain a carbonyl group.