| Abstract: | Abstract Values of the conditional stability constant of the copper(II)-Eriochrome Red B complex in aqueous solutions of pH 3–6 have been determined employing a cupric ion electrode. When the ionic strength of the solution is 0.01, the value of the second acidity constant (pk2) of Eriochrome Red B is 6.28 and the logarithm of the stability constant of the copper complex, log kCuHI, about 8.2. The complex can be used as an indicator in the ocapleximetric titration of cupric ion with EDTA at pH values from 4 to 8. |
