(a) Give chemical tests to distinguish between
(i) Phenol and Benzoic acid
(ii) Benzophenone and Acetophenone
(b) Write the strucutre of the main products of following reactions :
(i)
(ii) `H_(3)C - C -= C- H overset(Hg^(2+),H_(2)SO_(4))rarr`
.

Explanation

(i) Phenol and Benzoic acid : Phenol gives a violet colouration with neutral `FeCl_(2)` solution while benzoic acid buff coloured ppt ferric benzoate .
`6C_(6)H_(5) - OH + FeCl rarr underset(" violet colouration")([Fe(OC_(6)H_(5))]^(3-) + 3H^(+) + 3HCl`
`3C_(6)H_(5)COOH + FeCl_(3) rarr underset(" Ferric benzoate")((C_(6)H_(5) - COO)_(3) Fe + 3HCl`
(ii) Benzophenone and Acetophenone : Acetophenone gives yellow cystals of idoform on reaction with `I_(2)` and `NaOH`.
b