Question

Which of the following should be most volatile?

(I) $CH_{3}CH_{2}CH_{2}NH_{2}$ (II) $(CH_{3})_{3}N$

(III) (IV) $CH_{3}CH_{2}CH_{3}$

• A. II
• B. IV
• C. I
• D. III

Answer 1

Answer: (B)

IV

Answer 2

: The order of boiling points of isomeric amines is $1º$amines > $2º$amines > $3º$amines

Because of absence of H-atom available for hydrogen bonding, $3º$amines do not have intermolecular association. Intermolecular association is more in $1º$amines than in $2º$ amines as there are two H-atoms available for H-bonding. hydrocarbons are almost non-polar molecules and possess weak van der Waals forces and hence has lowest boiling point i.e. most volatile.