Question

The boiling points of aldehydes and ketones lie in between alkanes and alcohols of comparable masses because:

• A. alkanes are polar
• B. aldehydes and ketones are non-polar
• C. alkanes are non-polar and aldehydes and ketones contain polar group and lower alcohols have H-bonding
• D. alkanes are held together by weak van der Waals’ forces (being non-polar), aldehydes and ketones contain polar and held together by strong dipole-dipole attraction and lower alcohols have H-bonding, which is stronger than dipole-dipole attraction

Answer 1

The correct option is D alkanes are held together by weak van der Waals’ forces (being non-polar), aldehydes and ketones contain polar and held together by strong dipole-dipole attraction and lower alcohols have H-bonding, which is stronger than dipole-dipole attraction

Alcohols have hydrogen bonding and this tendency decreases in the order $-OH>-CHO>ketones>R-H$