Write balanced chemical equations for the following :(a) Combustion of methane in air.(b) Reaction of ethanol with sodium metal.(c) Reaction of ethanoic acid with ethanol in the presence of concentrated sulphuric acid.

Answer:

(a) Methane burns in air with a blue flame, giving carbon dioxide, water, heat and light:

\[\mathrm{CH_4 + 2O_2 \rightarrow CO_2 + 2H_2O + heat + light}\]

(b) Ethanol reacts with sodium to form sodium ethoxide and hydrogen gas (effervescence is seen):

\[\mathrm{2CH_3CH_2OH + 2Na \rightarrow 2CH_3CH_2ONa + H_2\uparrow}\]

(c) Esterification: ethanoic acid and ethanol, warmed with concentrated H₂SO₄, form ethyl ethanoate (a sweet-smelling ester) and water:

\[\mathrm{CH_3COOH + CH_3CH_2OH \xrightarrow{conc.\ H_2SO_4} CH_3COOCH_2CH_3 + H_2O}\]