Question

The exact order of boiling points of the compounds $n$-pentane, isopentane, butanone and $1$ -butanol is

• A. $n$-pentane $<$ isopentane $<$ butanone $<1$-butanol
• B. isopentane $<n$-pentane $<$ butanone $<1$-butanol
• C. butanone $<n$-pentane $<$ isopentane $<1$-butanol
• D. $1$-butanol $<$ butanone $<n$-pentane $<$ isopentane

Answer 1

Answer: (B)

As intermolecular force varies as:
$H$ bonding $>$ dipole dipole force $>$ vander waals force
$\therefore$ boiling point order
$n$-butanol $>$ butanone $>n$-Pentane $>$ iso pentane