10.2.3 - Alcohol Reactions

Question 1

Complete combustion

Answer 1

Alcohol + oxygen -> carbon dioxide + water

Question 2

Incomplete combustion

Answer 2

Alcohol + oxygen -> carbon monoxide + water

OR

Alcohol + oxygen -> carbon + water

Question 3

Oxidation - conditions

Answer 3

Presence of oxidising agent:

• Potassium manganate (VII)
• Acidified potassium dichromate (VI)

Question 4

Partial oxidation - primary alcohol

Answer 4

Primary alcohol -> aldehyde (+ hydrogen)

Question 5

Full oxidation - primary alcohol

Answer 5

Primary alcohol -> carboxylic acid

Question 6

Oxidation - secondary alcohol

Answer 6

Secondary alcohol -> ketone (C=O in the middle of the carbon chain)

Question 7

Oxidation - tertiary alcohol

Answer 7

No reaction. Tertiary alcohols can’t be oxidised.

Question 8

Acidified potassium manganate (VII) colour change in reduction

(when manganate reduced to manganese)

Answer 8

Purple -> colourless

Question 9

Acidified potassium dichromate (VI) colour change in reduction

(dichromate reduced to Cr^3+ ion)

Answer 9

Orange -> green

Question 10

Esterification

Answer 10

Alcohol + carboxylic acid -> ester + water (condensation reaction)

Question 11

Esterification conditions

Answer 11

Strong acid catalyst, e.g. sulfuric acid