Auric iodide

Gold-hydroxyd, n. gold hydroxide, specif, auric hydroxide, gold(III) hydroxide, -jodid, n. gold iodide, specif, auric iodide, gold(III) iodide, -jodiir, n. aurous iodide, gold (I) iodide, -kafer, m. gold beetle. 

Auric iodide, Aul3.—Gradual addition of a solution of auric chloride to one of potassium iodide yields complex AuI4-ions, converted by further addition of auric chloride into auric iodide 18... 

Auri-iodic Acid, HAuI4.—Hydrogen iodide converts aurous iodide, auric iodide, and gold in presence of free iodine into auri-iodic acid. It forms small, black crystals. 

Crystallization of a solution containing auric chloride and potassium iodide in the molecular proportions 1 4 yields potassium auri-iodide, KAuI4. It forms black crystals which begin to decompose at 66° C., and on strong heating leave a residue of crystalline gold.2 Water decomposes it, forming auric iodide. Johnston has also prepared an auri-iodide of sodium, ammonium, barium, and ferrous iron respectively and a strontium auri-iodide in solution. 

Write the chemical formulas for (a) cupric sulfide ib) stannous fluoride (c) plumbous chloride id) ferric iodide (e) auric nitrate if ) mercuric sulfide. 

In 1819 Pelletier 2 found Au=288 by analysing aurous iodide. Two years later, Javal3 found Au=201 by analysing auric oxide, and Au=104 by analysing potassium aurichloride. In 1823 Figuier4 found Au = 179 from the analysis of sodium aurichloride. These very inaccurate results are in striking contrast to Berzelius s value. 

Metallurgy of gold. Aurous chloride, aurous bromide, aurous iodide, potassium aurous cyanide, auric chloride, hydrogen aurichloride. 

The quaternary iodides are crystalline compounds, form platini-chlorides, and with chlorine yield iododicMorides of the type R4ASI.CI2. Some aliphatic-aromatic arsonium iodides combine with metallic salts such as mercwic halides, auric chloride, and cadmiumiodide, whilst iodoform also forms addition compounds with some derivatives. Treatment of the iodides with a boiling suspension of silver chloride replaces the iodine by chlorine, giving R4ASCI. The latter also results when hydrochloric add is added to hydroxides of the type R4AS.OH. The hydroxides are derived from the iodides by boiling the latter with a suspension of silver oxide in water or alcohol. It is not always possible to isolate a crystalline product from this reaction, and the syrups often isolated soon absorb carbon dioxide from the air. 

It is precipitated by potassium chromate, ferricyanide, bismuthi-iodide, and mercuri-iodide, ammonium molybdate, platinic chloride, and auric chloride [1]. 

Tetrabenzylphosphonium iodide, (CgHg.CH2)4PI, occurs when one part of phosphonium iodide and two parts of benzyl alcohol are heated together for six to eight hours in a sealed tube at 100° C. It forms white crystals, M.pt. 191° C., readily soluble in chloroform, ether or alcohol, becoming slightly yellow on exposure to the air. This iodide may be transformed in the usual manner into the chloride, bromide, sulphate or nitrate, all of which form white, shining crystals. Double salts are obtained with platinic chloride, and auric, mercuric and stannic chlorides. A picrate is known. 

White precipitates are formed when a 1% solution of cusparine is treated with phosphotungstic, phosphomolybdic or tannic acids, or with mercuric chloride or potassium mercuri-iodide. Picric acid, platinic chloride or potassium chromate give yellow precipitates, auric chloride or potassium bismuth iodide brown, and potassium ferrocyanide bluish-white (36). By treating a solution of cusparine hydrobromide with bromine water, a series of bromocusparine polybromides is obtiuned(38). 

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