Ncert Exercises & Solutions

Which of the following compounds contain all the carbon atoms in the same hybridisation state?

1. $H - C \equiv C - C \equiv C - H$

2. ${CH}_{3} - C \equiv C - {CH}_{3}$

3. ${CH}_{2} = C = {CH}_{2}$

4. ${CH}_{2} = CH - CH = {CH}_{2}$

(a, d)

Hybridisation of carbon atoms in different compounds is shown below

(a)

\underset{sp}{HC} \equiv \underset{sp}{C} - \underset{sp}{C} \equiv \underset{sp}{CH}

(b)

\underset{{sp}^{3}}{{CH}_{3}} - \underset{sp}{C} \equiv \underset{sp}{C} - \underset{{sp}^{3}}{{CH}_{3}}

(c)

\underset{{sp}^{2}}{{CH}_{2}} = \underset{sp}{C} = \underset{{sp}^{2}}{{CH}_{2}}

(d)

\underset{{sp}^{2}}{{CH}_{2}} = \underset{{sp}^{2}}{CH} - \underset{{sp}^{2}}{CH} = \underset{{sp}^{2}}{{CH}_{2}}

In options (a) and (b), all carbon atoms are in same hybridisation state i.e., in sp and sp² hybridisation respectively.