Browse Questions

# Yellow ammonium sulphide solution is a suitable reagent for the separation of

(a) $HgS$ and $PbS$
(b) $PbS$ and $Bi_2S_3$
(c) $Bi_2S_3$ and $CuS$
(d) $CdS$ and $As_2S_3$

Answer: $CdS$ and $As_2S_3$

Since $CdS$ belongs to II A group and $As_2S_3$ belongs to II B group, they can be separated with yellow ammonium sulphide as only II B group sulphides dissolve in yellow ammoium sulphide.
edited Jan 29, 2014