[poll id=”99″]
ANSWER: B. 2,2-Dimethylpropane
The general trend is the higher # of carbons, the higher the boiling point and melting point. There is a specific rule for this however that involves symmetry and branching. If the compound has branching and symmetry, then it has a higher melting point than its non-branched and symmetrical counterpart, which, in this example, 2,2-dimethylpropane (having 5 carbons) and pentane (also having 5 carbons, but lacking any branches).