Molybdenum(VI) equilibria at high perchloric acid concentration

被引：33

作者：

Cruywagen, JJ ^{[1
]}

Heyns, JBB ^{[1
]}

机构：

[1] Univ Stellenbosch, Dept Chem, ZA-7600 Stellenbosch, South Africa

来源：

POLYHEDRON | 2000年 / 19卷 / 08期

基金：

新加坡国家研究基金会;

关键词：

equilibrium constants; molybenum(VI) cations; thermodynamic quantities;

D O I：

10.1016/S0277-5387(00)00331-4

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

Equilibria involving the protonation and dimerization of MoO2(OH) (H2O)(3)(+) at high perchloric acid concentration have been investigated. A value for the protonation constant has been determined, log K= - 2.23 +/- 0.09. Values for the enthalpy and entropy changes for the reaction are Delta H= - 21.4 +/- 1.8 kT mol(-1) and Delta S = - 90 +/- 6 J mol(-1) K (-1) in 6.29 M HClO4. For the dimerization reaction the values pertaining to 3.0 M Na(H)ClO4 are Delta H = - 30 +/- 5 kJ mol(-1) and Delta S = - 63 +/- 10 J mol(-1) K-1 as determined by enthalpimetric titrations. Thermodynamic quantities for the conversion of [MoO4](2-) to the various mono- and dinuclear cationic species are reported. (C) 2000 Elsevier Science Ltd All rights reserved.

引用

页码：907 / 911

页数：5

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