In the wet way, arsenious oxide and arsenites, acidified with hydrochloric acid, give a yellow precipitate of arsenic trisulphide on the addition of sulphuretted hydrogen; this precipitate is soluble in solutions of the alkaline hydroxides, ammonium carbonate and yellow ammonium sulphide.
The arsenites of the alkali metals are soluble in water, those of the other metals are insoluble in water, but are readily soluble in acids.
Arsenides, Arsenites, &c. - Several iron arsenides occur as minerals; lolingite, FeAs 2, forms silvery rhombic prisms; mispickel or arsenical pyrites, Fe2AsS2, is an important commercial source of arsenic. A basic ferric arsenite, 4Fe2O3 As2O3.5H 2 O, is obtained as a flocculent brown precipitate by adding an arsenite to ferric acetate, or by shaking freshly prepared ferric hydrate with a solution of arsenious oxide.
There he made analyses of phosphates and phosphites, arsenates and arsenites, confirming the conclusions of J.