In each pair, choose the compound you would expect to have the highest boiling/melting point.
(a)

Intermolecular forces are the attractive forces between molecules that influence physical properties like boiling and melting points. The main types include hydrogen bonding, dipole-dipole interactions, and London dispersion forces. Compounds with stronger intermolecular forces generally exhibit higher boiling and melting points due to the increased energy required to overcome these attractions.

Molecular weight, or molar mass, refers to the mass of a molecule based on the sum of the atomic weights of its constituent atoms. Generally, compounds with higher molecular weights have higher boiling and melting points because larger molecules have more electrons, leading to stronger London dispersion forces. This trend is particularly evident in nonpolar compounds.

Functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. Different functional groups can significantly affect the boiling and melting points of compounds. For example, alcohols, which contain hydroxyl (-OH) groups, typically have higher boiling points than hydrocarbons of similar molecular weight due to hydrogen bonding.