Chemistry

Problem

Column-I	Column-II
(A) Colourless gas evolved on addition of dil. $\text{H}_2\text{SO}_4$	(P) $\text{S}_2\text{O}_3^{2-}$
(B) White ppt. on addition of $\text{AgNO}_3$	(Q) $\text{S}^{2-}$
(C) Black ppt. obtained when $\text{HgCl}_2$ is added in little amount	(R) $\text{NO}_2^-$
(D) The ppt. obtained on addition of $\text{AgNO}_3$ followed by $\text{NH}_3$ solution	(S) $\text{CH}_3\text{CO}_2^-$