NORMSERVIS s.r.o.

ISO 4281:1977

Sodium hexafluorosilicate for industrial use — Determination of free acidity and total hexafluorosilicate content — Titrimetric method

NORMA vydána dne 1.3.1977

Anglicky -
Elektronické PDF (1345.20 CZK)
Anglicky -
Tištěné (1345.20 CZK)


Francouzsky -
Elektronické PDF (1345.20 CZK)
Francouzsky -
Tištěné (1345.20 CZK)

The information about the standard:

Designation standards: ISO 4281:1977
Publication date standards: 1.3.1977
The number of pages: 2
Approximate weight : 6 g (0.01 lbs)
Country: International technical standard
Kategorie: Technické normy ISO

Annotation of standard text ISO 4281:1977 :

Description / Abstract: With respect to the free acidity, applicable to products having contents, expressed as H2 SiF6 , equal to or more than 0,1 % (m/m). First, determination of the free acid contents by titration of an ice-cooled test portion with a standard volumetric sodium hydroxide solution in the presence of potassium nitrate and using bromothymol blue as indicator, then, followed by titration at near boiling temperature with standard volumetric sodium hydroxide solution to the appearance of a permanent blue colour.