The principle consists in evaporation of the test portion, taking up by means of hydrochloric acid and reduction of iron(III) by means of hydroxylammonium chloride. Formation of an iron(II)-2.2'-bipyridyl complex in a buffered medium at a pH value between 4.5 and 6. Photometric measurement of the coloured complex at a wavelength of about 522 nm.

General information

  • Status :  Withdrawn
    Publication date : 1968-12
  • Edition : 1
    Number of pages : 5
  • :
    ISO/TC 47
  • 71.060.30

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