Boegli, Jacques S
Typescript, etc. / Digitized by Kansas State University Libraries
Huber, Harry Lee,
Thesis (PH. D.)--University of Chicago, 1917. / "Private edition, distributed by the University of Chicago Libraries, Chicago, Illinois." "Reprinted from the Journal of pharmacology and experimental therpeutics, Vol. XI, No. 4, May, 1918." Bibliography: p. 328-329.
Robertson, P. W.
Thesis (doctoral)--Universität Leipzig, 1909. / Vita. Includes bibliographical references.
Byerley, John Joseph
The kinetics of the carbon monoxide reduction of Cu(II) to Cu(I) in aqueous solutions were studied at 120°C and carbon monoxide pressures up to 1360 atm. The reduction was followed spectrophoto-metrically in a high pressure titanium cell specifically developed for studying reactions between transition metal ions and gaseous reducing agents. The observed kinetics in acetate-buffered solutions yield a rate law of the form [ Formula omitted ] The rate law describes a reaction that occurs by two parallel paths, one of which is effectively independent of pressure and is accounted for by a stable carbon monoxide complex, described by Cu(CO)+. The pressure-dependent path contains both a pH-dependent and pH-independent reaction. The observed kinetics are consistent with the following mechanism which includes the insertion of a carbon monoxide molecule between a copper ion and a co-ordinated water molecule. [ Formulas omitted ] The effect of complexing was found to be quite minor. This was further verified by studies in sulphate and perchlorate solutions. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate
Macgregor, Edwin Robert
The thesis describes a kinetic study of the reactions between cupric salts and hydrogen in aqueous solution. The first part is concerned with the homogeneous activation of hydrogen in solution by cupric perchlorate, as evidenced by its catalytic effect on the reaction between dichromate and hydrogen. These studies, which were conducted on solutions of higher acidity than previously investigated, provide further support for the mechanism proposed for this reaction, i.e., Cu⁺⁺ + H₂[formula omitted] CuH⁺+ H⁺ CuH⁺ + Cu"⁺⁺" □(→┬(k₂) ) 2Cu⁺ + H⁺ 2Cu⁺ + substrate □(→┬fast ) 2Cu⁺⁺ + products and the corresponding rate equation: (d[H^2])/dt = (k^₁ [Cu^(++) ]^2 [H^2])/((k^(-1)/(k^2 [H^+ ] )+[Cu^(++)]) The second part deals with the thermodynamics and kinetics of the precipitation of metallic copper from aqueous solution by H₂. The reduction reactions were studied in both cupric perchlorate and cupric sulphate solutions and the effects of a number of variables on the reaction rate in both systems are compared. The rate, which was initially fast, decreased gradually until an apparent steady-state condition was approached. This behavior was common to both systems, although the rates were much higher and the. residual copper concentration lower in the sulphate system. This apparent steady-state is not predicted by thermodynamics and is considered to result from kinetic factors. The dependence of the reaction rate on a number of variables can be predicted from the mechanism Cu⁺⁺ + H₂[formula omitted]CuH^++H⁺ CuH⁺ + Cu⁺⁺□(→┬(K₂) ) 2Cu⁺ + H⁺+ + 2Cu² □(→┬fast ) Cu° + Cu⁺⁺ which corresponds to an overall reaction of Cu⁺⁺ + H₂ → Cu° + 2H⁺ Reasonably good quantitative agreement between the predicted and measured kinetic dependence on Cu⁺⁺, H⁺ and H₂ concentration suggests that the rate of reduction of cupric salts is determined by the homogeneous activation of H₂ by Cu⁺⁺+ or a cupric complex. Although the initial decrease in rate can be predicted by this mechanism, the apparent steady-state condition approached cannot be fully explained. The equilibrium constant for the reaction 2Cu⁺ ⇌ Cu⁺⁺ + Cu° was also determined experimentally at several temperatures and compared with calculated values. / Applied Science, Faculty of / Mining Engineering, Keevil Institute of / Graduate
[Formulae and special characters can only be approximated here. Please see the pdf version of the abstract for an accurate reproduction.] Group 15 Lewis base adducts of Group 11 coinage metal salts of the form MX : L (1:n), where M=Cu(I),Ag(I),Au(I); X=(pseudo-)halide (Cl,Br,I,SCN,CN) and oxyanion; L-uni- or bi-dentate pnicogen ligand and n=1-4, may adopt monomeric, dimeric, oligomeric or polymeric structural forms. For the purpose of this study, the pnicogen bases are divided into two groups: the 'harder' nitrogen base ligands and 'softer' phosphine/arsine/stibine ligands. A sizeable body of structural data exits for adducts of silver(I) salts. Those with uni-dentate nitrogen base ligands are usually restricted to readily accessible liquid bases such as pyridine and its derivatives. The extension of such series to encompass ligands with more varied base characteristics may assist in the access of new bonding modes and stereochemistry, leading to control of these and of stoichiometry. Herein a number of complexes of copper(I) salts with uni-dentate nitrogen and bi-dentate phosphine/arsine/stibine adducts with differing degrees of complexity have been characterized, extending the known range of structural forms. Systematic variations in stoichiometry, halide, ligand and solvent of crystallization have provided a range of complexes whose structures have been determined by single crystal X-ray diffraction techniques. The structural relationship between these and other known adducts, often including their silver analogues, are considered, permitting comparisons of various common features and differences. The first section of this thesis (Chapter 3 and Chapter 4) reports a number of complexes of the form CuX : L (1:n) (CuX)Ln, L=uni-dentate nitrogen base ligand with n=1-3, the second section (Chapter 5 through Chapter 10) reports adducts with bi-dentate bis(diphenylpnicogeno)alkane ligands, Ph2E(CH2)xEPh2 (whereE=P,AS,Sb and x=1-6). The structural types and copper(I) coordination environments are influenced by CuX (salt) : ligand stoichiometry, the stereochemistry and basicity of the ligand, the type and size of the counter-ion (where applicable) and crystallization solvent. The structural types found for copper(I) (pseudo-)halide and oxyanion species are similar to those found for their silver(I) analogues, although the transitions between structural types may occur with different pnicogen and halide atoms, consequent on the smaller size of the copper(I) ion and differences in stereochemical preferences.
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