Question

C₆H₆Cl₆ on treatment with KOH produces
(a) C₆H₆ (b) C₆H₆Cl₄
(c) C₆H₃Cl₃ (d) C₆H₆OH

Answer 1

Explanation:

I think the correct answer is (c)

Answer 2

If C₆H₆Cl₆ has anti configuration between chlorine and hydrogen atom, then product will be (c) C₆H₃Cl₃. If the configuration is syn, then reaction does not occurs.

For the given reaction to take place in presence of alcoholic KOH, all chlorine and all hydrogen atom should be placed on same side with syn and anti configuration respectively.

On heating, hydrogen is removed by elimination reaction, specifically E2 mechanism is followed. With hydrogen, chlorine too is removed.

Reaction is given below -

C₆H₆Cl₆ + alcoholic KOH --> C₆H₃Cl₃ + HCl

C₆H₆Cl₆ is benzene hexachloride, KOH is potassium hydroxide, HCl is hydrochloric acid and (c) C₆H₃Cl₃ is 1,2,3 trichloro benzol.

If C₆H₆Cl₆ has one chlorine as syn and next hydrogens as syn and so on, the reaction will not take place.