Branching and boiling point

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I know that increased branching causes a decrease in boiling point for an alkane, but the examples of branching I've seen have always been really obvious. On a practice question, it asked to compare the boiling points of 2,2-dimenthylpentane and 2,3-dimethylpentane. How do you go about this?

The correct answer was that 2,2-dimenthylpentane is more branched, and has a lower boiling point.

Thanks!

 

[pmahesh107]

Just draw out both structures, it becomes pretty clear that 2,2-dimethylpentane branches 3 times on the terminal end whereas 2,3-dimethylpentane only branches once on two different carbons. Remember why branching affects BP......branching decreases a compounds ability to "stack" therefore decreasing chances of van der Waals interaction and decreasing MP and BP