Q. The correct order of boiling point for primary (1${^\circ}$), secondary (2${^\circ}$) and tertiary (3${^\circ}$)alcohols is
A) 1${^\circ} > 2{^\circ} > 3{^\circ}$
B) 3${^\circ} > 2{^\circ} > 1{^\circ}$
C) 2${^\circ} > 1{^\circ} > 3{^\circ}$
D) 2${^\circ} > 3{^\circ} > 1{^\circ}$
Explanation
(a)
Alcohols with same molecular weight are expected to have almost same boiling point however two more factors other than molecular weight are important, they are namely H-boiling and surface area of molecule. Both these factors are least in 3${^\circ}$ alcohols and maximum in $1{^\circ}$ alcohols. Hence, $3{^\circ}$ alcohols have least boiling point while $1{^\circ}$alcohols have maximum boliling point.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.