Chemical elements
    Physical Properties
    Chemical Properties
      Carbon Tetrafluoride
      Carbon Tetrachloride
      Carbon Tetrabromide
      Carbon Tetraiodide
      Carbon Oxychloride
      Carbonyl Chloride
      Carbon Oxybromide
      Carbonyl Bromide
      Carbon Suboxide
      Carbon Monoxide
      Carbon Dioxide
      Percarbonic Acid
      Carbamic Acid
      Carbon Disulphide
      Carbonyl Sulphide
      Carbon Oxysulphide
      Thiocarbonyl Chloride
      Thiocarbonic Acid
      Thiocarbamic acid
      Carbon Monosulphide
      Carbon Subsulphide
      Carbon Sulphidoselenide
      Carbon Sulphidotelluride
      Carbon Nitrides
      Hydrocyanic Acid
      Prussic Acid
      Cyanogen Chloride
      Cyanogen Bromide
      Cyanogen Iodide
      Polymerised Cyanogen Halides
      Cyanic Acid
      Cyanuric Acid
      Fulminic Acid
      Thiocyanic Acid
      Sulphocyanic Acid
      Isoperthiocyanic Acid
      Cyanogen Sulphide
      Thiocyanic Anhydride
    Amorphous Carbon

Thiourea, CS(NH2)2

Thiocarbamide, Thiourea, CS(NH2)2. - Thiourea is formed by heating ammonium thiocyanate to 140° C., this salt undergoing an isomeric change analogous to that produced in ammonium cyanate by heat:


At the same time some guanidine thiocyanate, NH:C(NH2)2.HSCN, is produced, though a larger proportion of this latter substance is formed at 170°-180° C. The thiourea is freed from guanidine thiocyanate and unchanged ammonium thiocyanate by cold water, in which the thiourea is but sparingly soluble; it is then purified by recrystallisation from water.

A better method of preparation consists in heating carbon disulphide (6 grams) with ammonium carbonate (8 grams) in a sealed tube at 160° C., when the yield is quantitative.

Thiourea crystallises in rhombic prisms, and dissolves in eleven times its weight of cold water. When heated with water to 140° C. it reverts to ammonium thiocyanate. It forms salts analogous to those of urea; the most characteristic of these is the nitrate, CS(NH2)2.HNO3.

© Copyright 2008-2012 by