Given below are organic compounds labelled A to F. Answer the questions that follow:

(a) Which compound forms a single product with bromine?

(b) Which two compounds have the same molecular formula?

(c) Which two compounds will react together in the presence of concentrated H₂SO₄ to form a product with a fruity smell?

(a) C

(b) D and F

(c) A and B

Reason

(a) C reacts with bromine to give a single product 1,2-dibromoethane

$\underset{\text{ ethene}}{\text{C}$2\text{H}4} + \text{Br}2 \xrightarrow[\text{[inert solvent]}]{\text{CCl}4} \underset{\text{1,2, dibromooethane [ethylene bromide]}}{\text{C}2\text{H}4\text{Br}_2}

(b) D is a straight-chain butane and F is a branched isobutane or 2-methylpropane, they have the same molecular formula C₄H₁₀ and are structural isomers of each other.

(c) A is a carboxylic acid (CH₃COOH) and B is an alcohol (CH₃CH₂OH). In presence of concentrated H₂SO₄ they undergo esterification to give ethyl ethanoate (ethyl acetate), which has a fruity smell.

$\underset{\text{ethyl alcohol}}{\text{C}$2\text{H}5\text{OH}} + \text{CH}3\text{COOH} \xrightarrow{\text{conc. H}2\text{SO}4} \underset{\text{ethyl acetate}}{{\text{CH}3\text{COOC}2\text{H}5}} + \text{H}_2\text{O}