Journal of Solution Chemistry

, Volume 10, Issue 7, pp 479–487 | Cite as

Dissociation constant of aqueous trifluoroacetic acid by cryoscopy and conductivity

  • John B. Milne
  • Timothy J. Parker
Article

Abstract

The dissociation constant of trifluoroacetic acid in aqueous solution has been determined at 25°C by electrical conductivity (0.65 mol-l−1) and at 0°C by cryoscopy (1.05 mol-l−1) and electrical conductivity (0.98 mol-l−1). The good agreement between the values of the constant determined by cryoscopy and conductivity at 0°C lends confidence to the value at 25°C determined by electrical conductivity. The constant determined at 25°C is in reasonable agreement with values determined by differential refractometry (0.92 mol-l−1) and from acidity function data (0.80 mol-l−1) reported by other workers. This work renews confidence in the electrical conductivity method for determining dissociation constants of moderately strong acids.

Key words

Trifluoroacetic acid dissociation constant cryoscopy electrical conductivity ionization constant acidity 

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Copyright information

© Plenum Publishing Corporation 1981

Authors and Affiliations

  • John B. Milne
    • 1
  • Timothy J. Parker
    • 1
  1. 1.Department of chemistryUniversity of OttawaOttawaCanada

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