PROOFS OF THE PBOPBETIES OF PLATINA.

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SECT. II.

EXPERIMENTAL PROOFS

OF

THE PROPERTIES OF PLATINA.

Experiment I.

Platina is soluble in nitro-muriatic acid ..

Jf one part of platina and ten of nitro-muriatic acid be presentedto each other a violent action takes place, and the platina becomesdissolved. On evaporating the solution, very small crystals ofmuriate of platina are deposited.

Remark. ..This is the only saline combination of this metal, ofwhich the properties have been examined ; it appears that theplatina exists in the solution in two states of oxidation. On add-ing potash to it, a precipitate is formed which is a triple com-pound of the alcali, acid, and platina highly oxidated; it is spar-ingly soluble in water and of a saline nature. When more pot-ash is added, another precipitate is thrown down, which is theimperfect oxid of platina.

Ammonia acts in a similar manner on the solution; and themuriate of ammonia likewise forms a triple compound of oxid ofplatina, muriatic acid, and ammonia, which being insoluble isprecipitated. By this property of aff ording a precipitate on theaddition of muriate of ammonia to its solution, platina is distin-guished from every other metal.

M 3