Question

Which of the following compound has highest boiling point?

• A. $n-hexane$
• B. $2,3$$-dimethylbutane$
• C. $2,2$$-dimethylbutane$
• D. $2$$-methylbutane$

Answer 1

The correct option is A $n-hexane$

Branching of alkanes decreases the surface area as the surface area decreases boiling point also decreases.

The boiling point increases with an increase in molar mass.

$2-methylbutane$ contains 5 carbon atoms while other compounds contain 6 carbon atoms.

Here $2,3-dimethylbutane$, $2,2-dimethylbutane$, are branched alkanes, but $n-hexane$ is a straight-chain alkane, so n-hexane has a highest boiling point.

Option A is correct.