Copper(II) oxide
Monoclinic
- Kupfermonoxid
- Cuprum oxydatum
- Cuprioxyd
Black, amorphous or crystalline solid
Fixed
6.48 g · cm -3
1326 ° C
Thermal decomposition: 1026 ° C
Insoluble in water, soluble in dilute acids, soluble in ammonium hydroxide
Attention
0.1 mg · m-3 (measured as the inhalable aerosol fraction)
Template: Infobox chemical / molecular formula search is not possible
Copper ( II) oxide is a chemical compound containing copper and oxygen. In this oxide with the formula CuO copper is divalent. Copper (II ) oxide is a black, amorphous or crystalline solid.
Occurrence
In the nature of copper ( II) oxide is present as the mineral tenorite. Tenorite results from the weathering of copper sulfides and therefore is usually found in the oxidized parts of copper deposits. The mineral is named after the Italian botanist Michele Tenore.
Production and representation
Copper ( II) oxide can be obtained by thermal decomposition (pyrolysis ) of copper ( II) nitrate or copper (II ) carbonate are presented.
Copper ( II) oxide may also be prepared by heating ( freshly precipitated ) of copper ( II) hydroxide. The copper (II ) hydroxide is precipitated by the addition of alkali to a Cu ( II) salt solution.
Copper ( II) oxide is formed in conjunction with copper ( I) oxide upon heating of metallic copper to red heat in air.
Properties
Copper ( II) oxide is insoluble in water and alcohols. However, it is soluble in dilute acids. By evaporation, the corresponding copper (II ) salts can be obtained. Copper (II ) oxide is soluble in ammonium hydroxide to form a complex.
Copper ( II) oxide readily adsorbed oxygen, nitrogen, carbon dioxide and other gases.
When heated above about 800 ° C. Copper (II ) oxide under reduced oxygen delivery to copper ( I) oxide.
To metallic copper and copper ( II) oxide is also formed together heated copper ( I) oxide.
Copper ( II) oxide is reduced at an elevated temperature by various reducing agents ( for example, carbon dioxide, carbon monoxide and hydrogen) to metallic copper.
By heating the copper (II ) oxide with hydrogen fluoride at 400 ° C. Copper (II ) fluoride is formed.
It has a monoclinic crystal structure with space group C2 / c (a = 4.683, b = 3.423, c = 5.129, ß = 95.54 °). Its enthalpy is -155.8 kJ / mol.
Use
Copper (II ) oxide is used as a pigment for coloring glass, ceramics, porcelain and created gemstones. In addition, it is used as a cathode material in batteries, as catalyst for the desulfurization of crude oil and for antifouling paints. Copper (II ) oxide is used as a starting material for the production of various copper compounds. Since the discovery of superconductivity of compounds of La2CuO4 ( doped with strontium ), and the subsequent discovery of additional hundred similar compounds not do for the most part without copper, and oxygen, cupric oxide is used for the ceramic superconductor, the are considered promising materials.