COMPOUNDS OF PHOSPHORUS. 429 



CHAPTER IV. 



COMPOUNDS OF PHOSPHORUS. 



Sulphuret of phosphorus. Phosphorus and sulphur unite in all 

 proportions, with the evolution of much heat, and sometimes 

 with explosion. These elements are most safely united under 

 hot water, of which the temperature, however, must not exceed 

 160, for otherwise sulphuretted hydrogen and phosphoric acid 

 may be produced with such rapidity as to occasion an explosion. 

 The compounds of phosphorus and sulphur obtained in this 

 manner appear not to be definite. They are more fusible and 

 more inflammable than phosphorus itself. Levol has shown 

 that they often contain a little of the persulphuret of hydrogen.* 

 Serullas appears to have formed a definite sulphuret of phos- 

 phorus, by acting upon the liquid terchloride of phosphorus by 

 sulphuretted hydrogen. Hydrochloric acid was evolved, and a 

 solid amorphous body, of a lemon-yellow colour remained^ which 

 was a tersulphuret of phosphorus, corresponding with phos- 

 phorous acid. Berzelius ascertained that the sulphurets of 

 phosphorus combine with sulphur bases, and produce colour- 

 less salts ; but he did not carry the investigation beyond that 

 point. 



Phosphuret of nitrogen, N 2 P. Both the chlorides of phos- 

 phorus absorb ammoniacal gas, and form solid white com- 

 pounds. The combination of the terchloride contains 2| equi- 

 valents of ammonia, but that of the perchloride, Rose did not 

 find equally definite. When exposed to a strong red heat, 

 without access of oxygen, these compounds leave a white amor- 

 phous body, which is the phosphuret of nitrogen. f It is most 

 easily prepared by transmitting a stream of dry carbonic acid 

 gas over the ammoniacal compound, in a tube of hard glass, 

 heated by a charcoal fire, so long as vapours of sal ammoniac 

 sublime. 



The phosphuret of nitrogen is not soluble in any menstruum, 

 nor acted upon by dilute acid or alkaline solutions. It is not 



* An. de Ch. et de Ph. t. 67, p. 332. f Rose, Ib. t.54, p. 275. 



