Chemical elements
    Physical Properties
    Chemical Properties
      Iridium Monochloride
      Iridium Dichloride
      Iridium Trichloride
      Potassium Chloriridite
      Sodium Chloriridite
      Ammonium Chloriridite
      Aquo Chloriridites
      Iridium Tetrachloride
      Potassium Chloriridate
      Sodium Chloriridate
      Ammonium Chloriridate
      Silver Chloriridate
      Thallium Chloriridate
      Iridium Tribromide
      Iridium Tetrabromide
      Potassium Bromiridate
      Sodium Bromiridate
      Ammonium Bromiridate
      Iridium Oxybromide
      Iridium Tri-iodide
      Potassium Iodiridite
      Iridium Tetra-iodide
      Potassium Iodiridate
      Iridium Monoxide
      Iridium Sesquioxide
      Iridium Dioxide
      Iridium Trioxide
      Iridium Monosulphide
      Iridium Sesquisulphide
      Iridium Disulphide
      Iridium Sesquisulphite
      Potassium Iridium Sulphite
      Iridium Sesquisulphate
      Potassium Iridium Alum
      Ammonium Iridium Alum
      Caesium Iridium Alum
      Rubidium Iridium Alum
      Iridium Disulphate
      Iridium Sesquiselenide
      Hydrogen Iridi-nitrite
      Potassium Iridi-nitrite
      Sodium Iridi-nitrite
      Ammonium Iridi-nitrite
      Hydrogen Iridicyanide
      Potassium Iridicyanide
      Barium Iridicyanide
    PDB 1c1k-4enb

Iridium Sesquisulphite, Ir2(SO3)3

Iridium Sesquisulphite, Ir2(SO3)3, may be obtained by exposing a suspension of the hydrated dioxide in water to a current of sulphur dioxide. The liquid becomes greenish in colour, and on standing deposits a yellow, crystalline precipitate of iridium sulphite. This salt is but slightly soluble in water. Alkalies convert it into the sesquioxide, which, upon exposure to air, oxidises to the dioxide. Acids liberate sulphur dioxide, converting the residue into the corresponding salt of iridium. When ignited, sulphur dioxide is expelled and a residue of iridium sesquioxide is obtained.

A second substance containing sulphur dioxide is described by Birnbaum as formed as a black, amorphous, insoluble residue during the preparation of the foregoing sesquisulphite. He regards it as a basic sulphite of tetravalent iridium, IrO2.SO2.4H2O, but it may equally well be a basic sulphate.

Iridium sesquisulphite combines with sulphites of the alkali metals to yield double salts.

© Copyright 2008-2012 by