Aqueous Ni II - chloro complexes

There is some uncertainty concerning this calculation. In [75LIB/TIA] Ni(C104)2 was used as a constant ionic medium (with a chloride concentration of 0.01 m), therefore, Ae can be calculated as Ae = e(NiCr, CIO4) - 8(Ni, CF) - s(Ni, CIO4). 

In this review, e(NiCF, CIO4) = (0.47 0.06) kg moF is used to determine Ae in other media to calculate log,o values from the rest of the data in Table V-10. 

According to Appendix B.2, the same treatment should be applied, e.g., for NOj, i.e., 8(1 1, NO3) should be replaced by 8(M, CIO4) if nitrate is part of the medium, but this recommendation is often disregarded. 

In [89IUL/POR] the authors proposed c(NiCr,C104) = 0.202 kg-moE, estimated from e(NP C104) = 0.375 kg-mol and (Na, CE) using Equation (B.22) (see Appendix B). Although luliano s value is considerably lower, we recommend the value derived in the present review for (NiCr, CIO4), since it is based on experimental evidence. 

These extrapolated values are considerably higher than the value determined from the data in [75LIB/TIA]. This is probably a result of the disregarded medium changes. Obviously, the attribution of the global effect (complex formation and changes in activity coefficients) to complex formation alone results in higher constants. 

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