PQ = Carboxylic acids and esters

Question 1

1-How are carboxylic acids made?

2-How are esters made?

Type of reaction?

Answer 1

1-Oxidisation of alcohol in the presence of potassium dichromate and sulphuric acid e.g. Ethanol to ethanal to ethanoic acid

2-Reacting an alcohol and carboxylic acid together. Condensation reaction.

Question 2

Name the process of making esters

Answer 2

Esterification

Question 3

How do you break the ester back into it’s alcohol and carboxylic acid?

Answer 3

Hydrolysis of esters.

React the ester with either a concentrated acid or concentrated alkali

e.g. HCl or NaOH

Question 4

How to identify esters

Answer 4

Esters have a distinctive smell, usually pleasant.

Question 5

Esters - Solubility in water?

Answer 5

Esters that have shorter chains are fairly soluble in water.

Solubility decreases as the length of the ester increases.

Question 6

Conditions for oxidising an alcohol

Answer 6

Potassium dichromate and sulphuric acid

1 atmosphere

50 degrees C