[3.3.8] Aldehydes & Ketones

Question 1

What is an aldehyde? How do you name it?

Question 2

What is an ketone? How do you name it?

Answer 2

Question 3

What are carbonyls?

Answer 3

Question 4

Describe the intermolecular forces in carbonyls.

Question 5

Describe the solubility of carbonyls.

Question 6

Describe the oxidation of primary, secondary and tertiary alcohols.

Answer 6

Question 7

What can aldehydes be oxidised to that ketones cannot be?

What reageants can be used and what are the conditions?

Answer 7

Question 8

Show the equation for the oxidation of ethanal.

Write the full ionic equation for this reaction too.

Answer 8

Question 9

What are the functional group tests for aldehydes?

In each case: what reagent is used, what are the conditions, what is the reaction and what can you observe?

Answer 9

Question 10

What reageant and conditions are used to reduce carbonyls?

Answer 10

Question 11

What do aldehydes reduce to?

What do ketones reduce to?

What are these reduction reactions an example of?

Answer 11

• Aldehydes reduce to primary alcohols.
• Ketones reduce to secondary alcohols.
• These reduction reactions are examples of nucleophilic addition.

Question 12

Write overall equation for the reduction reaction of propanal using [H] as the reductant.

Name the product.

Answer 12

Question 13

Write overall equation for the reduction reaction of propanone using [H] as the reductant.

Name the product.

Answer 13

Question 14

Outline the nucleophilic addition mechanism for the reduction reaction of propanone with NaBH₄ (the nucleophile should be shown as H–).

Answer 14

Question 15

How else can carbonyls be reduced other than via NaBH₄?

What reagent is used and in what conditions?

Answer 15

Question 16

Write equations for the catalytic hydrogenation of ethanal and propanone.

Answer 16

Question 17

What reagent, conditions and through what mechanism do carbonyls form hydroxynitriles?

Answer 17

Question 18

Write the overall equation between propanone and hydrogen cyanide.

Name the product.

Answer 18

Question 19

Write the overall equation between ethanal and hydrogen cyanide.

Name the product.

Answer 19

Question 20

Outline the nucleophilic addition mechanism for the reaction of propanone with KCN followed by dilute acid.

Answer 20

Question 21

What’s the advantage of using KCN or NaCN than HCN?

Answer 21

Question 22

What is the hazard of using KCN?

Answer 22

Toxic.

Question 23

Explain why nucleophilic addition reactions of KCN, followed by dilute acid, can produce a mixture of enantiomers.

Answer 23