316 



On Chemical Tests. 



[Oct. 



PROTOXIDE: (blue). 



Potash, flocky hydrate preci- 

 pitate nearly white changing to 

 grey, green, and finally reddish 

 brown, where in contact with the 

 atmosphere. 



Ammonia, same as potash : if 

 muriate of ammonia be present no 

 immediate precipitate, but on ex- 

 posure to the air a small green pre- 

 cipitate falls. 



Carbonate of potash, and carbo- 

 nate ammonia, white precipitate of 

 carbonate of iron, becoming green, 

 and then reddish brown, soluble 

 in muriate of ammonia, which 

 however lets fall a green precipitate 

 after standing exposed to the air. 



PEROXIDE: (red). 



Potash, Voluminous reddish 

 brown precipitate of hydrate of 

 iron. 



Ammonia, same as potash. 



Carbonates of potash, and ammo- 

 nia, reddish brown with both 

 tests. 



Phosphate of soda, white : if 

 Phosphate of soda white, turning ammonia be added brown, and af- 

 green. 1 ter some time completely dis- 



solves. 



Oxalic acid, after some time a 

 yellow precipitate of oxalate of 

 iron soluble in muriatic acid. 



Oxalic acid,, no precipitate, but 

 a yellow colour. 



Prussiate of potash, light blue Prussiate of potash, immediate 

 changing dark. Insoluble in mu- dark blue; insoluble in muriatic 

 riatic acid. acid. 



Red prussiate potash, immedi- 

 ate dark blue. Insoluble in acids. 



Hydros dphuret of ammonia, 

 black, being sulphuret of iron, 

 turning reddish brown in air. This 

 brown colour distinguishes iron 

 from nickel and cobalt. 



Red prussiate of potash, no pre- 

 cipitate. 



Hydrosulphuret of ammonia, 

 black pre ipitate becoming red- 

 dish brown in air. 



Liquid sulphuretted hydrogen, 

 Liquid su 7 phuretted hydrogen ; and sulphuretted hydrogen gas, in 

 and sulphuretted hydrogen gas. — neutral solutions a milky white 

 No precipitate. precipitate of sulphur; and the so- 



lution becomes protoxide. 



Muriate of 5 Precipitate becomes gradually purple, but a little car- 

 gold. I bonate of soda should be added. 



