The melting point of phenol is 40.5∘C and that of toluene is −95∘C. What is the best explanation for this difference? Select the
correct answer below: a. The (−OH) group on phenol can form hydrogen bonds, and the −CH3 group on toluene cannot. b. Phenol has only one hydrogen on the −OH group available to form hydrogen bonds, so the hydrogen bond is stronger. c. In toluene, the hydrogen bond is spread over all three hydrogens on the methyl group, so the interaction is weaker overall. d. Phenol has a higher molecular mass than toluene. e. None of the above.
a. The (−OH) group on phenol can form hydrogen bonds, and the −CH3 group on toluene cannot.
Explanation:
Hello,
We firs must consider that the hydroxyl functional group is present in phenol as a highly polar section into its structure. Thus, phenol molecules are strongly associated by the presence of hydrogen bonds which toluene does not have due to its apolarity.
Consequently, since associating interactions are present in the phenol but absent in the toluene, more energy must be supplied to the phenol to melt it down, that is why phenol's melting point is higher than toluene's that one.
The (−OH) group on phenol can form hydrogen bonds, and the −CH3 group on toluene cannot.
Phenol has only one hydrogen on the −OH group available to form hydrogen bonds, so the hydrogen bond is stronger. In toluene, the hydrogen bond is spread over all three hydrogens on the methyl group, so the interaction is weaker overall.
