The principle is based on the dissolution, in hot hydrochloric acid, of the residue from the determination of the ash of a test portion (see ISO 1389/8). Reduction, by hydroxylammonium chloride, of the iron(III) contained in the solution thus obtained, formation of the coloured complex iron(II)-2,2'bipyridyl in a buffered medium. Photometric measurement of the coloured complex at a wavelength of about 510 nm. - ISO 1389, Parts 1 to 11, replace ISO Recommendation R 1389-1970.

General information

  • Status :  Withdrawn
    Publication date : 1977-03
  • Edition : 1
    Number of pages : 3
  • :
    ISO/TC 47
  • 71.080.50

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