Question

Account for the following:
(a) The C-Cl bond length in chloro-benzene is shorter than that in `CH_3 - Cl`.
(b) Chloroform is stored in closed dark brown bottles.

Answer 1

(i) This is due to partial double bond character of C - Cl bond in chlorobenzene due to resonating structures.
(ii) Chloroform in the presence of air gets oxidised to phosgene which is poisonous our compand- Phosgene is carbonyl chloride and is represented as `COCl_2`. To prevent the formation of phosgene, chloroform is stored in dark coloured bottles. The reaction is represented as.
`CHCl_3+1/2O_2toCOCl_2+HCl`.