International Standard
ISO 6840:1982
Cationic surface active agents (Hydrochlorides and hydrobromides) — Determination of critical micellization concentration — Method by measurement of counter ion activity
Reference number
ISO 6840:1982
Edition 1
International Standard
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ISO 6840:1982
Published (Edition 1, 1982)
This standard was last reviewed and confirmed in 2019. Therefore this version remains current.

ISO 6840:1982

ISO 6840:1982
CHF 42
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The determination is carried out as follows: Potentiometric determination of the chloride or bromide ion activity of a series of solutions of cationic surface active agents the concentration of which cover the expected micellization concentration. Plotting the graph of potential as a function of the logarithm of the concentration; the c.m.c. corresponds to the singularity on this curve. The method is applicable to purified cationic surface active agents (hydrochlorides and/or hydrobromides), which are soluble in water and which have a Krafft temperature below 60 degree Celsius.

General information

  •  : Published
     : 1982-10
    : International Standard under systematic review [90.20]
  •  : 1
     : 3
  • ISO/TC 91
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