Question

the boiling point of n-butyl alcohol isobutyl alcohol sec-butyl alcohol and tert-butyl alcohol are 118⁰C 108⁰c 99.5⁰c and 82⁰c respectively. Explain ​

Answer 1

The boiling point of n-butyl alcohol isobutyl alcohol sec-butyl alcohol and tert-butyl alcohol are 118⁰C 108⁰c 99.5⁰c and 82⁰c respectively because the Boiling point depends upon the extent of branching.

• More the extent of branching less will be the boiling point. Hence n-butyl alcohol has the max boiling point because it's structure is linear followed by sec-butyl alcohol and tert-butyl alcohol.

Answer 2

the boiling point of n-butyl alcohol isobutyl alcohol sec-butyl alcohol and tert-butyl alcohol are 118⁰C 108⁰c 99.5⁰c and 82⁰c respectively because:

• The number of carbon is the same, and the molecular formula is the same, i.e. the molar mass is the same.

• The boiling point decreases as the degree of branching increases.
• The surface area reduces as the extent of branching increases, and the Van der Waal's forces of attraction diminish.
• The boiling point is lowered as a result of this. As a result, the boiling point is proportional to the molecular weight, which is proportional to the surface area.