Over deze norm
Applicable to products having a free acidity, expressed as H2 SO4 , equal to or more than 0.01 % (m/m). Dissolution of a test portion in Water and titration with standard volumetric sodium hydroxide solution in the presence of an indicator. The indicator must have a colour change in the pH range between 5.2 and 5.6. Has also been approved by the IUPAC.
|Engelse titel||Ammonium sulphate for industrial use - Determination of free acidity - Titrimetric method|