Question

Which compound in solution produces a precipitate with aqueous ammonia that does not dissolve when an excess of ammonia is addedQ6A solution of a metal ion when treated with KI gives a red precipitate which dissolves in excess KI to give a colourless solution. Moreover, the solution of metal ion on treatment with a solution of cobalt (II) thiocynate gives rise to a deep blue crystalline precipitate. The metal ion is
1 point
(a) Pb2+
(b) Hg2+
(c) Cu2+
(d) Co2+​

Answer 1

Answer:

A milky white precipitate was formed when solution containing aluminum cations is treated with ammonium hydroxide. The white precipitate does not dissolve on adding excess ammonia solution. No further reaction is seen on heating. A WHITE ppt was formed on treating cadmium cations with ammonium hydroxide which does not dissolve immediately on adding xs ammonia. No reaction is seen on heating, apart from the formation of a few white ppt. Cadmium Hydroxide was precipitated which formed a complex soluble ion on adding xs ammonia.