หมายเลขมาตรฐาน : ISO 2762:1973
ชื่อเรื่อง : Hydrochloric acid for industrial use — Determination of soluble sulphates — Turbidimetric method
The turbidimetric method is applicable to products containing less than 0.1 % (m/m) of soluble sulphates. The principle consists in evaporation of a test portion to dryness and solution of the residue in hydrochloric acid. Measurement of the turbidity obtained by precipitation, under well defined conditions, of barium sulphate. Has also been approved by the IUPAC.
Link : https://www.iso.org/standard/7742.html
