Reference number
ISO 3423:1975
ISO 3423:1975
© ISO 2025
International Standard
ISO 3423:1975
Sulphuric acid and oleums for industrial use — Determination of sulphur dioxide content — Iodometric method
Edition 1
1975-11
1975-11
ISO 3423:1975
8739
Published
(Edition 1, 1975)
This publication was last reviewed and confirmed in 2025.
Therefore this version remains current.
Abstract
Applicable of products the SO2 content of which is equal to or more than 2 mg/kg. Based on the displacement of the sulphur dioxide present in the test portion by a current of pure nitrogen and absorption in a known volume of iodine solution. Titration of the excess of iodine with standard volumetric sodium thiosulphate solution. The diagram of the glass apparatus for absorption is shown in a figure.