Gold , thermodynamic

Oxygen Reactivity. Silver is second only to gold as the element having the weakest interaction with oxygen, providing silver with its superior sparking and combustion resistance. Silver must be oxidized chemically or electrolyticaHy to form AggO. Thermodynamically, silver exists only in the... 

The thermodynamics of copper smelting are discussed ia References 17 and 18. Silver and gold are quantitatively recovered with the copper throughout the smelting operations rather than being lost with the slag. 

In the presence of oxygen and water the oxides of most metals are more thermodynamically stable than the elemental form of the metal. Therefore, with the exception of gold, the only metal which is thermodynamically stable in the presence of oxygen, there is always a thermodynamic driving force for corrosion of metals. Most metals, however, exhibit some tendency to passivate, ie, to form a protective oxide film on the surface which retards further corrosion. 

A reversed, reductive TCA cycle would require energy input to drive it. What might have been the thermodynamic driving force for such a cycle Wachtershanser hypothesizes that the anaerobic reaction of FeS and H9S to form insoluble FeS9 (pyrite, also known as fool s gold) in the prebiotic milieu could have been the driving reaction ... 

This high thermodynamic activity shows that gold is extremely unstable in an oxygenated cyanide solution. 

Gold-copper, alloy (Au5Cu5, AuBCuB(S)), calculation of thermodynamic quantities, 136, 142 solid solution (CuAu), 129 Gold-lead, alloy (Au5Pb5), calculation of thermodynamic quantities, 136 Gold-nickel, alloy (Au5Ni8), calculation of thermodynamic quantities, 136, 142... 

Gold-thallium, alloy (Au5T15), calculation of thermodynamic quantities, 136... 

Silver-copper, energy of solutions, 142 Silver-gold, excess entropy, 132, 136 excess free energy, 136 Silver-lead, alloy (AgsPb5), calculation of thermodynamic quantities, 136 Silver-zinc, alloy (Ag5Zn5), 129... 

The first thing to point out is that the use of a pentafluorophenyl CgFs group with late transition metal confers on the complexes great stability, both thermodynamic and kinetic. This general fact, that is also true in gold chemistry, can be explained by different factors ... 

Chui, Y.H., Grodiola, G., Snook, l.K. and Russo, S.P. (2007) Molecular dynamics investigation of the structural and thermodynamic properties of gold nanodusters of different morphologies. Physical Review B - Condensed Matter, 75, 033404-1-033404-4. 

If the thiomalate ligand is not present in excess, it is completely displaced. When gold binds, the M ions are displaced in the gold metal ratio of 3 2, which suggests bidentate coordination. EXAFS data shows AuS2 coordination with Au—S bond lengths of 229 pm [20, 103]. In the presence of both cadmium and zinc, zinc is preferentially displaced which is possibly a consequence of thermodynamics as Zn7MT and CdyMT react at comparable rates. 

Kanayama, N., Tsutsumi, O., Kanazawa, A. and Ikeda, T. (2001) Distinct thermodynamic behaviour of a mesomorphic gold nanoparticle covered with a liquid-crystalline compound. Chemical Communications, (24), 2640-2641. 

Self-assembled monolayers (SAMs) [8] The layers are formed by heterologous interaction between reactive groups, such as thiols, and noble metals, such as gold or silver. Since the molecules are selectively adsorbed on these metals, film growth stops after the first monolayer is completed. The molecular aggregation is enthalpy driven, and the final structure is in thermodynamic equilibrium. 

White, J.L., Ore, R.L. and Hultgrev. R. (1957) The thermodynamic properties of silver-gold alloys. Acta Metallurgica, 5, 747-760. 

From the thermodynamic behavior of metals pertinent to gold leaching in cyanide solutions it may be observed that Au(CN) shows a large region of stability over the whole pH range, whilst metallic gold, which is usually stable in aqueous solutions under all condi-... 

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