Which of the following are correct chain isomers of butane ?
(i)

Options

A. II
B. IV
C. I
D. III

Answer

B

Explanation

`1^(@) and 2^(@)` amines have higher boiling points due to intermolecular H-bonding but less volatile than `3^(@)` amines and hydrocarbons of comparable molecular mass. Further, because of polar C-N bonds, `3^(@)` amines are more polar than hydrocarbons which are almost non-polar. Hence, due to weak dipole-dipole interaction, `3^(@)` amines have higher boiling point (i.e., less volatile) than hydrocarbons. In other words, hydrocarbons are more volatile among given compounds as amine are less volatile than hydrocarbon.