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Updated: Jun 28, 2026

Collecting Variable-concentration Isothermal Titration Calorimetry Datasets in Order to Determine Binding Mechanisms
Published on: April 7, 2011
Analytical data: Potentiometric study of the association constant of isothiocyanic acid
E A Neves1, L Angnes, G O Chierice
1Instituto de Química da Universidade de São Paulo, São Paulo, Cx. Postal 20780, Brazil.
Abstract:
The association constant of isothiocyanic acid, HNCS, has been determined potentiometrically and found to be 0.135 +/- 0.007 and 0.168 +/- 0.007 at ionic strengths (NaClO(4)) of 2.0 and 4.0M respectively. The indicator electrode was Hg(SCN)(2-)(4)/Hg. For accuracy and precision the metal phase was used in the form of a dropping electrode. Because the association constant is so low, liquid-junction potentials would cause significant errors, since a strong acid was added to the working solutions in the procedure, and an estimate of this effect was taken into account.
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