Cyanic acid, ammonium salt

This same substitution of sulphur for oxygen occurs in the case of cyanic acid and its salts, e.g., potassium thio-cyanate and ammonium thiocyanate used as reagents in testing for ferric iron. 

Ammonium Cyanate.— The corresponding ammonium salt, viz., ammonium cyanate, NH4OCN, may be easily prepared from the potassium cyanate by treating a solution of the latter with the calculated amount of ammonium sulphate. This compound is of especial interest because on evaporation of the water solution to dryness a rearrangement takes place and urea is formed (p. 429). Ammonium cyanate is also formed when iso-cyanic acid is neutralized with ammonia. 

Alkyl Ureas.—By substituting alkyl amines for ammonia in the reaction for the synthesis of urea from carbonyl chloride, or by using alkyl derivatives of ammonium cyanate (cyanic acid salts of alkyl amines), in the Wohler synthesis, alkyl ureas may be obtained. They are of different t es as illustrated by the following formulas showing their relationship to urea. 

I can no longer, as it were, hold back my chemical urine and I have to let out that I can make urea without needing a kidney, whether of man or dog the ammonium salt of cyanic acid is urea. ... 

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