Question

Which type of organic chemical reaction (addition reaction or substitution reaction ), is shown by Ethene

Answer 1

1. Unsaturated hydrocarbons are those which have double or triple bonds between $\mathrm{C}-\mathrm{C}$ atoms. Thus Ethene $({\mathrm{C}}_2{\mathrm{H}}_4)$comes under unsaturated hydrocarbons.
2. Unsaturated hydrocarbons (alkene, alkyne) generally show addition reactions.
3. Example showing addition reaction in unsaturated hydrocarbon: Ethene is treated within ${\mathrm{Br}}_2$ the presence of Carbon tetrachloride $\left({\mathrm{CCl}}_4\right)$ to produce an addition reaction product.
4. The addition chemical reaction of Ethene is as follows.

$\underset{\mathrm{Ethene}}{{\mathrm{C}}_2{\mathrm{H}}_4\left(\mathrm{g}\right)}+\underset{\mathrm{Bromine}}{{\mathrm{Br}}_2\left(\mathrm{l}\right)}\stackrel{{\mathrm{CCl}}_4}{\to }\underset{1,2,\mathrm{dibromoethane}}{{\mathrm{CH}}_2\mathrm{Br}-{\mathrm{CH}}_2\mathrm{Br}}$