Hydrocarbon $\left(\mathrm{A}\right)$ reacts with bromine by substitution to form an alkyl bromide which by Wurtz reaction is converted to gaseous hydrocarbon containing less than four carbon atoms. $\left(\mathrm{A}\right)$ is

Which of the following reactions is used for producing symmetrical alkane with double carbon atoms?

Assertion (A): Sodium acetate on Kolbe's electrolysis gives ethane.

Reason (R): Methyl free radical is formed at cathode.

State one relevant reason for the following:

• Soda-lime is preferred to sodium hydroxide in the laboratory preparation of methane.

Write a balanced chemical equation for the following:

• Producing ethane from bromo-ethane using $\mathrm{Zn}/\mathrm{Cu}$ couple in alcohol.