Copper发表评论(0)编辑词条

Copper is a chemical element with the symbol Cu (Latin: cuprum) and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is rather soft and malleable and a freshly-exposed surface has a pinkish or peachy color. Gold, caesium and copper are the only metallic elements with a natural color other than gray or white. It is used as a thermal conductor, an electrical conductor, a building material, and a constituent of various metal alloys.

Copper has played a significant part in the history of mankind, which has used the easily accessible uncompounded metal and its alloys for thousands of years. Evidence has been preserved from several early civilizations of the use of copper. In the Roman era, copper was principally mined on Cyprus, hence the origin of the name of the metal as Cyprium, "metal of Cyprus", later shortened to Cuprum.

Some countries, such as Chile and the United States, still have sizable reserves of the metal which are extracted through large open pit mines. However, like tin, there may be insufficient reserves to sustain current rates of consumption. High demand relative to supply caused a price spike in the 2000s.

Copper compounds are known in several oxidation states, usually 2+, where they often impart blue or green colors to natural minerals such as turquoise and have been used historically widely as pigments. Copper as both metal and pigmented salt, has a significant presence in decorative art.

Copper 2+ ions are soluble in water, where they function at low concentration as bacteriostatic substances and fungicides. For this reason copper metal can be used as an anti-germ surface that can add to the anti-bacterial and antimicrobial features of buildings such as hospitals.

In sufficient amounts, copper salts can be poisonous to higher organisms as well. However, despite universal toxicity at high concentrations, the 2+ copper ion at lower concentrations is an essential trace nutrient to all higher plant and animal life. In animals, including humans, it is found widely in tissues, with concentration in liver, muscle, and bone. It functions as a co-factor in various enzymes and in copper-based pigments. Some molluscs have blue-green blood resulting from the copper compound hemocyanin which they use to transport oxygen, instead of heme.

铜是人类最早发现的古老金属之一，早在三千多年前人类就开始使用铜。　

　
金属铜，元素符号Cu，原子量63.54，比重8.92,熔点1083oC。纯铜呈浅玫瑰色或淡红色,表面形成氧化铜膜后,外观呈紫铜色。铜具有许多可贵的物理化学特性，例如其热导率和电导率都很高，化学稳定性强，抗张强度大，易熔接，具抗蚀性、可塑性、延展性。纯铜可拉成很细的铜丝，制成很薄的铜箔。能与锌、锡、铅、锰、钴、镍、铝、铁等金属形成合金.