Aqueous and alcoholic solutions of ammonia convert carbon bisulphide into ammonium dithiocarbamate, which readily breaks down into ammonium thiocyanate and sulphuretted hydrogen (A.
For example, when a solution of a ferric salt is added to a solution of potassium thiocyanate, a deep red coloration is produced, owing to the formation of ferric thiocyanate.
But it is found that even when more than sixty times the amount of potassium thiocyanate required by this equation is added, a portion of the ferric nitrate still remains unconverted, doubtless owing to the occurrence of the reverse change Fe (CNS) 3 +3KNOs =Fe(N03) 3+3KCNS.
Chromic thiocyanate, Cr(SCN) 3, an amorphous deliquescent mass, is formed by dissolving the hydroxide in thiocyanic acid and drying over sulphuric acid.
The double thiocyanate, Cr(SCN) 3.3KCNS 4H 2 O, is also known.