Which of the following products is $NOT$ formed by the reaction between methane and chlorine in the presence of sunlight?

What are $X$ and $Y$ respectively in the following reaction sequence?
Isopentane $\xrightarrow{KMnO_4} X$ $\xrightarrow{\text{dehydration}} \underset{\text{Major}}{Y}$

The chemicals and the reaction conditions required for the preparation of ethane are:

An unknown compound $X$ on chlorination followed by Wurtz reaction and dehydrohalogenation gives ethene. Provide the complete reaction sequence in a stepwise manner.

Describe the Kolbe electrolysis reaction of $C_{2}H_{5}COO^{-}Na^{+}$ at the anode and cathode.

Hydrocarbon $(A)$ reacts with bromine by substitution to form an alkyl bromide,which by Wurtz reaction is converted to a gaseous hydrocarbon containing less than four carbon atoms. $(A)$ is