Question

Which among the following are unsaturated hydrocarbons?

1. \[\ce{H3C - CH2 - CH2 - CH3}\]
2. \[\ce{H3C - C ≡ C - CH3}\]
3. \[\begin{array}{cc}
   \ce{H3C - CH - CH3}\\
   |\phantom{..}\\
   \ce{CH3}\\
   \end{array}\]
4. \[\begin{array}{cc}
   \ce{H3C - C = CH2}\\
   |\\
   \phantom{...}\ce{CH3}\\
   \end{array}\]

Options

• (i) and (iii)

• (ii) and (iii)

• (ii) and (iv)

•  (iii) and (iv)

Answer 1

(ii) and (iv)

Explanation - 

Compounds (i) and (iii) are saturated compounds because the valencies of all the atoms are satisfied by single bonds between them. Compounds (iv) and (ii) are unsaturated compounds because there are double and triple bonds between the carbon atoms to satisfy their valencies.