Question

Give a chemical test to distinguish between the following :

(a) Ammonium chloride and sodium chloride,

(b) Ferric salt and ferrous salt,

(c) Sodium sulphate and ammonium sulphate.

Answer 1

(a) on strong heating sublimes to form dense white fumes which condense to white powdery mass on cooler parts of the tube whereas no white fumes on heating NaCl.
(b) When ammonium hydroxide is added drop wise to solution to be tested. Ferrous salt gives dirty green ppt. Ferric salt gives reddish brown ppt of their hydroxides.
(c) on warming with NaOH sol. gives gas. Sodium sulphate does not liberate gas.