An organic compound (A) `C_(2)H_(3)OCl` on treatment with Pd and `BaSO_(4)` gives (B) `C_(2)H_(4)O` which answers iodoform test. (B) when treated with conc. `H_(2)SO_(4)` undergoes polymerisation to give ( C) a cyclic compound. Identify (A), (B) and ( C) and explain the reactions.

Explanation

(i) Compound (A) must be acetyl chloride which undergoes Rosenmund's reduction giving acetaldehyde.
`underset((A))(CH_(3)COCl)overset(Pd//BaSO_(4))tounderset((B))(CH_(3)CHO)`
(B) undergoes iodoform reaction
`underset((B))(CH_(3)CHO)overset(I_(2)//NaOH)tounderset("Iodoform")(CHI_(3))+HCOONa`
(ii) Acetaldelyde (B) undergoes ploymerisation giving a cyclic compound