Ammonium nitrate, action with heat

When ammonium nitrate solutions are heated in contact with iron, an analogous reaction occurs ammonia is evolved, whilst the iron suffers appreciable corrosion under the action of the liberated nitric acid.3... 

Dilute aqueous ammonia has no action on realgar more concentrated solutions cause a dulling of the surface.7 Liquid ammonia dissolves it.8 Heated with a mixture of ammonium chloride and ammonium nitrate, realgar yields arsenic trichloride.9 When boiled with aqueous alkali, realgar reacts to yield the trisulphide and a precipitate of arsenic, thus—10... 

Cyanamide is also acted upon directly by ammonium salts in aqueous and non-aqueous solutions.17-20 Since it is of decided advantage to avoid the isolation of pure cyanamide, methods have been developed in which aqueous solutions of cyanamide are prepared from calcium cyanamide and are then permitted to react with ammonium salts. However, guanidine nitrate may also be prepared directly from commercial calcium cyanamide by the action of ammonium nitrate. This reaction takes place readily in the fused state, in concentrated aqueous solution,21 or by direct admixture of solid ammonium nitrate with calcium cyanamide and subsequent heating to 100°C.22 The latter procedure is to be preferred, since better yields are obtainable and the hazard of fusion with ammonium nitrate is obviated. The directions given for procedure B require the use of a fairly good grade of unoiled calcium cyanamide containing approximately 65 per cent CaNCN. 

Action of heat The result varies with the metal. The nitrates of sodium and potassium evolve oxygen (test with glowing splint) and leave solid nitrites (brown fumes with dilute acid) ammonium nitrate yields dinitrogen oxide and... 

The amidine or iso-carbamide formula, H0.C(NH).NH2 (Butlerov, 1868).—Urea is a neutral solute, and has not the alkalinity implied by the presence of two amide groups. With strong acids only monobasic salts are formed, for example, urea nitrate, CON2H4. HNO3. The difficulty with which urea is obtained by the action of heat on ammonium carbamate is in striking contrast with the ease with which amides are prepared from the corresponding ammonium salts. 

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