Chloroform oxidizes in the presence of light to
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Phosgene
Chloroform is slowly oxidised by the oxygen of air in the presence of light. The product is carbonyl chloride (phosgene), an extremely poisonous gas:
\( \displaystyle \ce{2CHCl3 + O2} \xrightarrow{\text{light}} \ce{2COCl2 + 2HCl} \)
The C–H bond of chloroform is oxidised, and the carbon ends up bonded to one oxygen and two chlorine atoms.
So chloroform oxidises in light to phosgene. For this reason it is stored in closed, dark coloured bottles filled up to the brim, so that air and light are kept out.
NCERT (2026-27 edition):
Trichloromethane (Chloroform)
