Question

Explain the following briefly:

t-butyl bromide has a lower boiling point than n-butyl bromide.

Answer 1

1. n-butyl bromide and t-butyl bromide are isomers having the same molecular formula (C₄H₉Br) but different structures.
2. n-butyl bromide has a straight-chain structure, whereas t-butyl bromide has a branched-chain structure.
3. Straight-chain molecules have a larger surface area than branched-chain molecules.
4. Due to the larger surface area, n-butyl bromide molecules experience stronger van der Waals’ intermolecular forces.
5. Stronger intermolecular forces require more energy (heat) to separate the molecules.

Therefore, the boiling point of n-butyl bromide is higher, while the boiling point of t-butyl bromide is lower.