Copper — golden-pink plastic metal, on air quickly becomes covered by an oxidic film which gives it a characteristic intensive yellowish-red shade. Thin films of copper on a gleam have greenish-blue color.
Along with osmium, caesium and gold, copper — one of four metals having obvious color coloring, excellent from gray or silvery at other metals. This color shade is explained by existence of electronic transitions between filled with the third and thin atomic orbitals of the fourth: the power difference between them corresponds to the wavelength of orange light. The same mechanism is responsible for characteristic color of gold.
- Thanks to valuable qualities copper and copper alloys are used in electrotechnical and electromachine-building branch, in radio electronics and instrument making. There are copper alloys with such metals as zinc, tin, aluminum, nickel, titanium, silver, gold. Alloys with nonmetals are less often applied: phosphorus, sulfur, oxygen. Allocate two groups of copper alloys: brass (alloys with zinc) and bronze (alloys with other elements).
- Copper has high environmental friendliness that allows its use in construction of houses. For example, the copper roof due to anticorrosive properties, can serve more than hundred years without special leaving and painting.
- Copper in alloys with gold is used in jewelry. Such alloy increases product durability, increases resistance to deformation and attrition.
- High biological activity is characteristic of compounds of copper. In plants copper takes part in synthesis of a chlorophyll. Therefore it can be seen as a part of mineral fertilizers. The lack of copper of a human body can cause deterioration in composition of blood. It is as a part of many food. For example, this metal contains in milk. However it is important to remember that surplus of compounds of copper can cause poisoning. For this reason it is impossible to cook food in copper ware. During boiling a large amount of copper can get to food. If ware is covered with a layer of tin inside, then there is no danger of poisoning.
- In medicine copper is used as antiseptic and astringent. It is a component of eye drops from conjunctivitis and solutions from burns.