Question

The correct order of boiling point for primary $\left(1^o\right)$, secondary $\left(2^o\right)$ and tertiary $\left(3^o\right)$ alcohols is:

• A. $1^o>2^o>3^o$
• B. $3^o>2^o>1^o$
• C. $2^o>1^o>3^o$
• D. $2^o>3^o>1^o$

Answer 1

The correct option is A $1^o>2^o>3^o$

Alcohols with same molecular weight are expected to have almost some boiling point however two more factors other than molecular weight are important, they are namely H-bonding and surface area of the molecule. Both these factors are least in $3^o$ alcohols and maximum in $1^o$ alcohols. Hence, $3^o$ alcohols have a least boiling point while $1^o$ alcohols have a maximum boiling point.