The sulphydrate or hydrosulphide, Ca(SH)2, is obtained as colourless, prismatic crystals of the composition Ca(SH) 2.6H 2 O, by passing sulphuretted hydrogen into milk of lime.
Ammonium sulphide, (NH 4) 2 S, is obtained, in the form of micaceous crystals, by passing sulphuretted hydrogen mixed with a slight excess of ammonia through a well-cooled vessel; the hydrosulphide NH 4 ï¿½HS is formed at the same time.
The hydrosulphide 'NH' 4 ï¿½HS can be obtained as a white solid, by mixing well-cooled ammonia with a slight excess of sulphuretted hydrogen.
An ice-cold solution of this substance kept at o C. and having sulphuretted hydrogen continually passed through it gives the hydrosulphide.
The hydrosulphide, KHS, was obtained by Gay-Lussac on heating the metal in sulphuretted hydrogen, and by Berzelius on acting with sulphuretted hydrogen on potassium carbonate at a dull red heat.