The crude element is treated with aqua regia and then evaporated with an excess of hydrochloric acid, the solution diluted and the tellurium precipitated by a current of sulphur dioxide.
The iridium is then precipitated from the solution (as oxide) by the addition of baryta, dissolved in aqua regia, and precipitated as iridium ammonium chloride by the addition of ammonium chloride.
It is soluble in a mixture of nitric and hydrofluoric acids, and the powdered metal, in aqua regia, but slowly attacked by sulphuric, hydrochloric and hydrofluoric acids separately; it is also soluble in boiling potash solution, giving a tunstate and hydrogen.
The tetroxide, 0s04, is formed when osmium compounds are heated in air, or with aqua regia, or fused with caustic alkali and nitre.
It is obtained from zorgite by heating the mineral with aqua regia; the excess of acid is evaporated, and the resulting syrupy liquid diluted, filtered and decomposed by sulphur dioxide, when the selenium is precipitated (Billandot, Ency.
Nos pisciculi secundum Ixotn nostrum Jesum Christum in aqua nascimur.
Auric chloride, or gold trichloride, AuC1 3, is a dark rubyred or reddish-brown, crystalline, deliquescent powder obtained by dissolving the metal in aqua regia.
Bunsen by boiling iodine with aqua regia and extracting with ether.
It combines directly with the halogens, and dissolves in cold dilute sulphuric acid, in hot strong hydrochloric acid and in aqua regia, but less readily in nitric acid.
Fe2P forms crystalline needles insoluble in acids except aqua regia; it is obtained by fusing copper phosphide with iron.