Alkyl halides are colourless when pure. Which of them develop colour when exposed to light?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Bromides and iodides
Pure alkyl halides are colourless. Alkyl bromides and iodides, however, slowly develop colour when they are kept exposed to light.
NCERT (2026-27 edition):
6.6 Physical Properties – “Alkyl halides are colourless when pure. However, bromides and iodides develop colour when exposed to light. Many volatile halogen compounds have sweet smell.”