Write suitable chemical reaction for the preparation of methane from [2] i) sodium ethanoate ( CH 3COONa ) [1] ii) methyl magnesium iodide ( CH 3MgI ). [1] GROUP: B Attempt any five questions. 5×5=25

i) Preparation of methane from sodium ethanoate ($\mathrm{CH}{}_3\mathrm{COONa}$): Sodium ethanoate is heated with soda lime (a mixture of $\mathrm{NaOH}$ and $\mathrm{CaO}$). This reaction is known as decarboxylation, where the carboxyl group ($-\mathrm{COONa}$) is removed as sodium carbonate ($\mathrm{Na}{}_2\mathrm{CO}{}_3$), producing methane ($\mathrm{CH}{}_4$).

$$\mathrm{CH}{}_3\mathrm{COONa}+\mathrm{NaOH}\stackrel{\mathrm{\Delta },\mathrm{soda}\mathrm{lime}}{\to }\mathrm{CH}{}_4+\mathrm{Na}{}_2\mathrm{CO}{}_3$$

ii) Preparation of methane from methyl magnesium iodide ($\mathrm{CH}{}_3\mathrm{MgI}$): Methyl magnesium iodide (a Grignard reagent) reacts with water ($\mathrm{H}{}_2\mathrm{O}$) during hydrolysis. The carbon-magnesium bond is replaced by a carbon-hydrogen bond, yielding methane.

$$\mathrm{CH}{}_3\mathrm{MgI}+\mathrm{H}{}_2\mathrm{O}\to \mathrm{CH}{}_4+\mathrm{Mg}(\mathrm{OH})\mathrm{I}$$