Question

what type of alcohol is isoborneol?
monoterpenoid alcohol
what type of carbonyl compound is camphor?
bicyclic terpenoid ketone
isoborneol melts at 208 °c. why is the melting point of camphor lower (think inter-molecular forces)?

Explanation:

Step1: Analyze intermolecular forces

Isoborneol has an -OH group which can form hydrogen bonds. Hydrogen bonds are strong intermolecular forces. Camphor has a carbonyl group (C = O). The intermolecular forces in camphor are dipole - dipole forces (due to the polar C = O bond).

Step2: Compare strength of forces

Hydrogen bonds are stronger than dipole - dipole forces. Stronger intermolecular forces require more energy to break, resulting in a higher melting point.

Answer:

Isoborneol has hydrogen bonding (due to -OH group) which is stronger than the dipole - dipole forces (due to C = O group) in camphor. Stronger intermolecular forces (hydrogen bonds in isoborneol) lead to a higher melting point. So, camphor has a lower melting point as it has weaker dipole - dipole forces compared to the hydrogen bonds in isoborneol.