[Maximum number: 1]

Ethanoic acid can be reacted with alcohols to form esters, an equilibrium mixture being formed.

\mathrm{CH}_{3} \mathrm{CO}_{2} \mathrm{H}+\mathrm{ROH} \rightleftharpoons \mathrm{CH}_{3} \mathrm{CO}_{2} \mathrm{R}+\mathrm{H}_{2} \mathrm{O}

The reaction is usually carried out in the presence of an acid catalyst.

(a)

Esters are hydrolysed by sodium hydroxide. During the titration, sodium hydroxide reacts with ethanoic acid and the hydrogen chloride, but not with the ester.

Suggest a reason for this.

[ 1 ]

[Maximum number: 1]

Food additives are substances added to food to preserve the flavour or to improve its taste and appearance.

European Union legislation requires most additives used in foods to be labelled clearly in the list of ingredients, either by name or by an 'E number'. E296 is malic acid which occurs in unripe fruit.
Malic acid has the structural formula $\mathrm{HO}_{2} \mathrm{CCH}_{2} \mathrm{CH}(\mathrm{OH}) \mathrm{CO}_{2} \mathrm{H}$ .

(a)

Suggest one major commercial use of compounds such as A or B.

[ 1 ]

[Maximum number: 1]

Use of the Data Booklet is relevant to this question.
A sample of propyl ethanoate is hydrolysed by heating under reflux with aqueous sodium hydroxide. The two organic products of the hydrolysis are separated, purified and weighed.

Out of the total mass of products obtained, what is the percentage by mass of each product?

A

32.4 % and 67.6 %

B

38.3 % and 61.7 %

C

42.3\% and 57.7\%

D

50.0\% and 50.0\%

[Maximum number: 1]

Ester P has the following structural formula.
ester P

Which compounds are produced when P is hydrolysed using dilute hydrochloric acid?

A

$\mathrm{CH}_{3} \mathrm{COCl}$ and $\left(\mathrm{CH}_{3}\right)_{2} \mathrm{CHCH}_{2} \mathrm{CH}_{2} \mathrm{OH}$

B

$\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH}$ and $\left(\mathrm{CH}_{3}\right)_{2} \mathrm{CHCH}_{2} \mathrm{CO}_{2} \mathrm{H}$

C

$\mathrm{CH}_{3} \mathrm{CO}_{2} \mathrm{H}$ and $\left(\mathrm{CH}_{3}\right)_{2} \mathrm{CHCH}_{2} \mathrm{CO}_{2} \mathrm{H}$

D

$\mathrm{CH}_{3} \mathrm{CO}_{2} \mathrm{H}$ and $\left(\mathrm{CH}_{3}\right)_{2} \mathrm{CHCH}_{2} \mathrm{CH}_{2} \mathrm{OH}$

[Maximum number: 1]

The diagram shows the structure of ethanedioic acid.

Ethanedioic acid reacts with ethanol in the presence of a few drops of concentrated sulfuric acid to form a diester. The molecular formula of the diester is $\mathrm{C}_{6} \mathrm{H}_{10} \mathrm{O}_{4}$ .

What is the structural formula of the diester?

A

$\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CO}_{2} \mathrm{CO}_{2} \mathrm{CH}_{2} \mathrm{CH}_{3}$

B

$\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OCOCO}_{2} \mathrm{CH}_{2} \mathrm{CH}_{3}$

C

$\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{O}_{2} \mathrm{CO}_{2} \mathrm{CCH}_{2} \mathrm{CH}_{3}$

D

$\mathrm{CH}_{3} \mathrm{CO}_{2} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{OCOCH}_{3}$

[Maximum number: 1]

An ester with an odour of banana has the following formula.

Which pair of reactants, under suitable conditions, will produce this ester?

A

B

C

D

[Maximum number: 1]

Compound X reacts with ethanoic acid in the presence of an $\mathrm{H}^{+}$ catalyst to produce the compound below.

What is the molecular formula of compound X ?

A

$\mathrm{C}_{2} \mathrm{H}_{6} \mathrm{O}_{2}$

B

$\mathrm{C}_{2} \mathrm{H}_{6} \mathrm{O}_{3}$

C

$\mathrm{C}_{4} \mathrm{H}_{8} \mathrm{O}$

D

$\mathrm{C}_{4} \mathrm{H}_{8} \mathrm{O}_{2}$

[Maximum number: 1]

Compound C is used in textile and leather processing.

compound C

Which starting material(s), on gentle heating with a few drops of concentrated sulfuric acid, generates compound C ?

A

$\mathrm{CH}_{3} \mathrm{COOH}$ only

B

$\mathrm{HOCH}_{2} \mathrm{COOH}$ only

C

$\mathrm{CH}_{3} \mathrm{COOCH}_{2} \mathrm{COOH}$ only

D

$\mathrm{CH}_{3} \mathrm{COOH}$ mixed with $\mathrm{HOCH}_{2} \mathrm{COOH}$

[Maximum number: 1]

An ester with an aroma of pineapples can be synthesised in the laboratory from butanal using this reaction scheme.

What is the structural formula of the ester?

A

$\mathrm{CH}_{3}\left(\mathrm{CH}_{2}\right)_{2} \mathrm{CO}_{2}\left(\mathrm{CH}_{2}\right)_{2} \mathrm{CH}_{3}$

B

$\mathrm{CH}_{3}\left(\mathrm{CH}_{2}\right)_{2} \mathrm{CO}_{2}\left(\mathrm{CH}_{2}\right)_{3} \mathrm{CH}_{3}$

C

$\mathrm{CH}_{3}\left(\mathrm{CH}_{2}\right)_{3} \mathrm{CO}_{2}\left(\mathrm{CH}_{2}\right)_{2} \mathrm{CH}_{3}$

D

$\mathrm{CH}_{3}\left(\mathrm{CH}_{2}\right)_{3} \mathrm{CO}_{2}\left(\mathrm{CH}_{2}\right)_{3} \mathrm{CH}_{3}$

[Maximum number: 1]

An ester of structural formula $\mathrm{CH}_{3} \mathrm{CO}_{2} \mathrm{CH}_{3}$ is heated with an aqueous solution of sodium hydroxide.

What are the two organic products of this reaction?

A

ethanoic acid and methanol

B

methanoic acid and ethanol

C

sodium ethanoate and methanol

D

sodium methanoate and ethanol