Question

A compound X is used in making chloromethane as shown below. Identify X.

$X+{\mathrm{Cl}}_2\underset{\mathrm{UV}\mathrm{light}}{\overset{250°C-400°C}{\to }}{\mathrm{CH}}_3\mathrm{Cl}+\mathrm{HCl}$

• A. $C{H}_4$
• B. $C_2{H}_6$
• C. $C_3{H}_8$
• D. $C_4{H}_{10}$

Answer 1

The correct option is A $C{H}_4$

Methane $\left(C{H}_4\right)$ is used in making chloromethane $\left(C{H}_{3}Cl\right)$ as shown below.

${\mathrm{CH}}_4\left(g\right)+{\mathrm{Cl}}_2\left(g\right)\underset{\mathrm{UV}\mathrm{light}}{\overset{250°C-400°C}{\to }}{\mathrm{CH}}_3\mathrm{Cl}\left(g\right)+\mathrm{HCl}\left(g\right)$

This process is called chlorination of methane. It takes place in the presence of ultraviolet rays. However, ethane $\left(C_2{H}_6\right)$, propane $\left(C_3{H}_8\right)$ and butane $\left(C_4{H}_{10}\right)$ can also undergo chlorination to give chloroethane $\left(C_2{H}_{5}Cl\right)$, chloropropane $\left(C_3{H}_{7}Cl\right)$ and chlorobutane $\left(C_4{H}_{9}Cl\right)$ respecticely along with hydrogen chloride $\left(HCl\right)$ gas.