Question

predict the relationship between the melting points and boiling points of phenol and toluene. recall that toluene is a benzene ring with a single methyl substituent. select the correct choice below. select the correct answer below: both the melting and boiling points of phenol are lower that that of toluene. phenols melting point is lower than that of toluene, but its boiling point is higher. phenols melting point is higher than that of toluene, but its boiling point is lower. both the melting and boiling points of phenol are higher than that of toluene.

Explanation:

Phenol has hydroxyl group (-OH) which can form hydrogen bonds. Hydrogen bonds are strong intermolecular forces. Toluene has only van der Waals forces (weak London dispersion forces as it is non - polar). Stronger intermolecular forces (hydrogen bonds in phenol) require more energy to break. So, more energy is needed to change phenol from solid to liquid (higher melting point) and from liquid to gas (higher boiling point) compared to toluene.

Answer:

Both the melting and boiling points of phenol are higher than that of toluene.