On converting benzene to toluene, state whether there will be a rise or fall in the melting point

hydrocarbons
cbse

#1

On converting benzene to toluene, there is a fall in the melting point although toluene has the higher molecular mass. This is because the planar molecules of benzene can pack more closely in the crystal lattice and the cohesive forces are strong, whereas the methyl group in toluene prevents such close packing.