Question

Distinguish between the saturated hydrocarbon ethane and unsaturated hydrocarbon ethene.

Answer 1

Ethane ($C_2{H}_6$)	Ethene ($C_2{H}_4$)
The structure of Ethane is	The structure of Ethene is
It has Carbon-Carbon $\left(\mathrm{C}-\mathrm{C}\right)$ single bond .	It has Carbon Carbon $\left(\mathrm{C}=\mathrm{C}\right)$ double bond.
It is saturated hydrocarbon	It is unsaturated hydrocarbon.
Ethane undergo substitution reaction.	Ethene undergo addition reaction.
When few drops of alkaline Potassium permanganate$\left({\mathrm{KMnO}}_4\right)$ is added no change in color observed.	When few drops of Potassium permanganate is added purple color of solution fades.
When it is treated by Bromine ($B{r}_2$) water the color of solution does not change as it is saturated hydrocarbon	When it is treated by Bromine water the color of solution change red brown to colorless as it is unsaturated hydrocarbon
The Chemical reaction is as follows $\underset{\mathrm{Ethane}}{{\mathrm{C}}_2\mathrm{H}{\left(\mathrm{g}\right)}_6}+\underset{\mathrm{Bromine}}{{\mathrm{Br}}_2\left(\mathrm{l}\right)}\to \mathrm{No}\mathrm{reaction}$	The Chemical reaction is as follows. $\underset{\left(\mathrm{Ethene}\right)}{{\mathrm{CH}}_2={\mathrm{CH}}_2\left(\mathrm{g}\right)}+\underset{\left(\mathrm{Bromine}\right)}{{\mathrm{Br}}_2\left(\mathrm{l}\right)}\to \underset{(1,2-\mathrm{dibromo}\mathrm{Ethane})}{{\mathrm{CH}}_2\mathrm{Br}-{\mathrm{CH}}_2\mathrm{Br}\left(\mathrm{l}\right)}$