International Standard
ISO 4281:1977
Sodium hexafluorosilicate for industrial use — Determination of free acidity and total hexafluorosilicate content — Titrimetric method
Reference number
ISO 4281:1977
Edición 1
International Standard
Vista previa
ISO 4281:1977
No disponible en español
Publicado (Edición 1, 1977)
Esta norma se revisó y confirmó por última vez en 2023. Por lo tanto, esta versión es la actual.

ISO 4281:1977

ISO 4281:1977
CHF 42
Convertir Franco suizo (CHF) a tu moneda


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.

Informaciones generales

  •  : Publicado
     : 1977-03
    : Norma Internacional confirmada [90.93]
  •  : 1
     : 2
  • ISO/TC 47
  • RSS actualizaciones

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