Reference number
ISO/R 1982:1971
ISO/R 1982:1971
© ISO 2024
ISO/R 1982:1971
Nitric acid for industrial use — Determination of iron content — 2,2'- Bipyridyl photometric method
Edition 1
1971-05
1971-05
Withdrawn
Abstract
The method is applicable to the determination of iron contents greater than 0,0001 % (m/m). The principle consists in evaporation of a test portion, taking up by means of hydrochloric acid and reduction of iron(III) by means of hydroxylammonium chloride. Formation of iron(II)-2,2' -dipyridyl complex in ammonium acetate medium. Photometric measurement of the coloured complex at a wavelength of about 522 nm.