Question

Which of the following reactions can be used to prepare methane?

• A. Decarboxylation of sodium acetate
• B. Kolbe's electrolysis of sodium acetate
• C. Wurtz reaction
• D. Hydrogenation of alkenes

Answer 1

The correct option is A Decarboxylation of sodium acetate

A) Decarboxylation of sodium acetate $\left({CH}_{3}COONa\right)$ gives methane.

${CH}_{3}COONa+NaOH\stackrel{CaO/\Delta }{⟶}{CH}_4+{Na}_2{CO}_3$

B) Kolbe electrolysis of ${CH}_{3}COONa$ will give ethane not methane.

${2CH}_{3}COONa+2H_{2}O\stackrel{electrolysis}{⟶}{CH}_3-{CH}_3+2{CO}_2+H_2+2NaOH$

C) Wurtz reaction will give more than one carbon-containing alkane. So methane can't be prepared by the Wurtz reaction.

D) Hydrogenation of alkenes gives also more than one carbon-containing alkane, not methane.

Hence, option A is correct.