Germanium(II) hydroxide

Germanium(II) hydroxide, normally written as Ge(OH)2, is a poorly characterised compound, sometimes called hydrous germanium(II) oxide or germanous hydroxide. It was first reported by Winkler in 1886.[1]

Properties and preparation

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Germanium(II) hydroxide is formed as a white or yellow precipitate when base is added to solutions containing GeII, produced for example by the reduction of an acid solution of germanium dioxide, GeO2, with hypophosphorous acid, H3PO2,[2] or alternatively by hydrolysis of GeCl2.[3] The initial precipitate, which has no definite stoichiometry, can be represented by GeO·xH2O, Ge(OH)2·xH2O, or loosely Ge(OH)2. It is only slightly soluble in water or alkali[4] and not appreciably soluble in perchloric acid, HClO4,[2] but is soluble in hydrochloric acid, HCl.[2] On digestion with sodium hydroxide, NaOH, it yields a brown insoluble compound, which after drying in vacuo forms a brown pyrophoric substance with the approximate stoichiometry of (HGe)2O3. On the basis of the infrared spectrum, (HGe)2O3 may contain a germanium hydrogen bond, Ge-H.[4]

References

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  1. ^ Everest, David A.; Terrey, Henry (1950). "467. Germanous oxide and sulphide". Journal of the Chemical Society (Resumed): 2282. doi:10.1039/jr9500002282. ISSN 0368-1769.
  2. ^ a b c Babich, Olga A.; Ghosh, Manik C.; Gould, Edwin S. (2000). "Preparation of aqueous solutions of hypovalent germanium; reactions involving germanium-(ii) and -(iii)". Chemical Communications (11): 907–908. doi:10.1039/b000401o. ISSN 1359-7345.
  3. ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.
  4. ^ a b Yang, Duck J.; Jolly, William L.; O'Keefe, Anthony. (1977). "Conversion of hydrous germanium(II) oxide to germynyl sesquioxide, (HGe)2O3". Inorganic Chemistry. 16 (11): 2980–2982. doi:10.1021/ic50177a070. ISSN 0020-1669.