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The concept of plotting the free energies of reaction of various elements with a given gas-phase reactant may be extended beyond oxidation reactions. The original paper by Ellingham explicitly to the reduction of both oxygen and sulfur by metallurgical processes, [ 1 ] and anticipated the use of such diagrams for other compounds, including ...
A sample of copper(I) oxide. Copper forms a rich variety of compounds, usually with oxidation states +1 and +2, which are often called cuprous and cupric , respectively. [ 1 ] Copper compounds , whether organic complexes or organometallics , promote or catalyse numerous chemical and biological processes.
Copper oxide is any of several binary compounds composed of the elements copper and oxygen. Two oxides are well known, Cu 2 O and CuO, corresponding to the minerals cuprite and tenorite, respectively. Paramelaconite (Cu 4 O 3) is less well characterized. [1] Copper oxide may refer to: Copper(I) oxide (cuprous oxide, Cu 2 O) Copper(II) oxide ...
Given these assumptions, the flux of oxidant through each of the three phases can be expressed in terms of concentrations, material properties, and temperature. = = = where: is the gas-phase transport coefficient, is the concentration of oxidant in the surrounding atmosphere, is the concentration of oxidant in the surface of the oxide, is the concentration of the oxidant at the interface ...
The Frost diagram normally shows free-energy values above and below nE° = 0 and is scaled in integers. The y axis of the graph displays the free energy. Increasing stability (lower free energy) is lower on the graph, so the higher free energy and higher on the graph a species of an element is, the more unstable and reactive it is. [2]
Lithium dimethylcopper (CH 3) 2 CuLi can be prepared by adding copper(I) iodide to methyllithium in tetrahydrofuran at −78 °C. In the reaction depicted below, [4] the Gilman reagent is a methylating reagent reacting with an alkyne in a conjugate addition, and the ester group forms a cyclic enone. Scheme 1. Example Gilman reagent reaction
In addition the four copper atoms form a planar Cu 4 ring based on three-center two-electron bonds. The copper to copper bond length is 242 pm compared to 256 pm in bulk copper. In pentamesitylpentacopper a 5-membered copper ring is formed, similar to (2,4,6-trimethylphenyl)gold, and pentafluorophenylcopper is a tetramer. [9]