Carboxylic Acids and Derivatives

Organic compound X has the empirical formula $\text{C}_2\text{H}_4\text{O}$.

Compound X is reduced by $\text{LiAlH}_4$, but not by $\text{NaBH}_4$.

What is compound X?

Options

A   ethanoic acid
B   ethanal
C   butan-1-ol
D   butanoic acid

Skeletal formulae of four organic compounds are shown.

Which two compounds when separately heated with dilute sulfuric acid produce propanoic acid as one of the products?

Options

A   1 and 2
B   1 and 4
C   2 and 3
D   3 and 4

P is a compound that burns in an excess of oxygen to give carbon dioxide and water only.

$2.20\text{ g}$ of P contains $1.20\text{ g}$ of carbon and $0.20\text{ g}$ of hydrogen.

When P is added to a solution of sodium carbonate, bubbles of gas are seen.

What is P?

Options

A   $\text{CH}_3\text{CHO}$
B   $\text{CH}_3\text{CO}_2\text{H}$
C   $\text{CH}_3\text{COCH}_2\text{CH}_2\text{OH}$
D   $\text{CH}_3\text{CH}_2\text{CH}_2\text{CO}_2\text{H}$

Three reagents are listed.

1. aqueous sodium carbonate
2. $\text{LiAlH}_4$
3. water

Which reagents react with pure ethanoic acid to give a solution containing ethanoate ions?

Options

A   1 and 2
B   1 and 3
C   1 only
D   2 and 3

An organic compound J reacts with an excess of sodium to produce an organic ion with a charge of –3. J reacts with an excess of $\text{NaOH}(\text{aq})$ to produce an organic ion with a charge of –1.

What is the structural formula of J?

Options

A   $\text{HOCH}_2\text{CH}(\text{OH})\text{CH}_2\text{CO}_2\text{H}$
B   $\text{HO}_2\text{CCH}(\text{OH})\text{CH}_2\text{CHO}$
C   $\text{HO}_2\text{CCH}(\text{OH})\text{CH}_2\text{CO}_2\text{H}$
D   $\text{HOCH}_2\text{COCH}_2\text{CHO}$

Which formula represents the organic compound formed by the reaction of propanoic acid with methanol in the presence of concentrated sulfuric acid as a catalyst?

Options

A   $\text{CH}_3\text{CH}_2\text{COCH}_3$
B   $\text{CH}_3\text{CH}_2\text{CO}_2\text{CH}_3$
C   $\text{CH}_3\text{CO}_2\text{CH}_2\text{CH}_3$
D   $\text{CH}_3\text{CH}_2\text{CH}_2\text{CO}_2\text{CH}_3$

An ester, $\text{R}'\text{CO}_2\text{R}''$, is hydrolysed in alkaline conditions. $\text{R}'$ and $\text{R}''$ are different alkyl groups.

Which row identifies the two products formed?

Options

Propanoic acid reacts with $\text{LiAlH}_4$ to give organic product P.

Methanoic acid reacts with organic product P, in the presence of a few drops of concentrated sulfuric acid, to give organic product Q.

What are the skeletal formulae of the two organic products?

Options

The structure of butenedioic acid is shown.

When an excess of $\text{NaOH(aq)}$ is added to butenedioic acid, which organic product is formed?

Options

Four organic compounds are shown.

A mixture of these four compounds reacts with hot aqueous sodium hydroxide.

The products of this reaction are acidified.

Which organic acids are present in the products?

Options

A   butanoic, ethanoic and propanoic acids
B   butanoic, ethanoic and methanoic acids
C   ethanoic, 3-methylbutanoic and propanoic acids
D   methanoic, 3-methylbutanoic and propanoic acids