Question

Why do the boiling points of isomeric haloalkanes decrease with increase in branching?

Answer 1

The boiling points of isomeric haloalkanes decrease with increase in branching because:

1. Decrease in Surface Area: Branched haloalkanes have a more compact, spherical shape compared to straight-chain isomers. This reduces the surface area available for intermolecular van der Waals forces.
2. Weaker Intermolecular Forces: Lower surface area in branched isomers means weaker van der Waals attractions between molecules. Weaker forces are easier to overcome, so less energy (heat) is needed to boil the compound.