Question

What happens when methane reacts with chlorine? Write the chemical equations for the reactions.

Answer 1

Methane is an alkane having single carbon atom and four hydrogen atoms.

Methane $\mathrm{\left(}{\mathrm{CH}}_{\mathrm{4}}\mathrm{\right)}$ on reaction with Chlorine $\mathrm{\left(}{\mathrm{Cl}}_{\mathrm{2}}\mathrm{\right)}$ undergoes substitution reaction in presence of diffused sunlight giving carbon tetrachloride.

The reaction sequence involved can be as represented below:

1. $\underset{\left(\mathrm{Methane}\right)}{{\mathrm{CH}}_4\left(\mathrm{g}\right)}+{\mathrm{Cl}}_2\left(\mathrm{g}\right)\stackrel{\mathrm{Diffused}\mathrm{sunlight}}{\to }\underset{\left(\mathrm{Chloromethane}\right)}{{\mathrm{CH}}_3\mathrm{Cl}\left(\mathrm{g}\right)}+\mathrm{HCl}\left(\mathrm{g}\right)$
2. $\underset{\left(\mathrm{Chloromethane}\right)}{{\mathrm{CH}}_3\mathrm{Cl}\left(\mathrm{g}\right)}+{\mathrm{Cl}}_2\left(\mathrm{g}\right)\stackrel{\mathrm{Diffused}\mathrm{sunlight}}{\to }\underset{\left(\mathrm{Dichloromethane}\right)}{{\mathrm{CH}}_2{\mathrm{Cl}}_2\left(\mathrm{l}\right)}+\mathrm{HCl}\left(\mathrm{g}\right)$
3. $\underset{\left(\mathrm{Dichloromethane}\right)}{{\mathrm{CH}}_2{\mathrm{Cl}}_2\left(\mathrm{l}\right)}+{\mathrm{Cl}}_2\left(\mathrm{g}\right)\stackrel{\mathrm{Diffused}\mathrm{sunlight}}{\to }\underset{\mathrm{Chloroform}\left(\mathrm{Trichlormethane}\right)}{{\mathrm{CHCl}}_3\left(\mathrm{l}\right)}+\mathrm{HCl}\left(\mathrm{g}\right)$
4. $\underset{\left(\mathrm{Chloroform}\right)}{{\mathrm{CHCl}}_3\left(\mathrm{l}\right)}+{\mathrm{Cl}}_2\left(\mathrm{g}\right)\stackrel{\mathrm{Diffused}\mathrm{sunlight}}{\to }\underset{\left(\mathrm{Carbon}\mathrm{tetrachloride}\right)}{{\mathrm{CCl}}_4\left(\mathrm{l}\right)}+\mathrm{HCl}\left(\mathrm{g}\right)$