2-Methyl pentane has the highest point because the boiling point in alkene depends upon the chains of atoms and the molecular mass of the molecules. Straight-chain molecules have higher boiling point than the branched-chain compounds. Also, the lesser branched chain has low boiling point because in higher branched molecules, the molecular mass increases and boiling point also increases.
The boiling point order is as follows:
2-Methyl pentane > 2, 3-Dmethyl butane > 2, 2-Dimethyl butane
The boiling point decreases because branching increases.
