Identify the product $X$ in the following reaction: $CH_3-CH_2-COONa \xrightarrow[\Delta]{\text{soda-lime}} X + Na_2CO_3$

Ethyl iodide and $n$-propyl iodide are allowed to undergo Wurtz reaction. The alkane which will not be obtained in this reaction is

Which of the following alkanes with the lowest number of carbon atoms is optically active?

Knocking sound occurs in an engine when fuel:

$n$-Butane on monochlorination under photochemical conditions gives an optically active compound "$P$". "$P$" on further chlorination gives dichloro compounds. The number of dichloro compounds obtained (ignore stereoisomers) is:

Compound $(P)$ is