Search results
Results from the WOW.Com Content Network
Copper is one of the few metals that can occur in nature in a directly usable metallic form. This means that copper is a native metal. This led to very early human use in several regions, from c. 8000 BC.
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.
Molecules containing polar bonds have no molecular polarity if the bond dipoles cancel each other out by symmetry. Polar molecules interact through dipole-dipole intermolecular forces and hydrogen bonds. Polarity underlies a number of physical properties including surface tension, solubility, and melting and boiling points.
The tables below provides information on the variation of solubility of different substances (mostly inorganic compounds) in water with temperature, at one atmosphere pressure. Units of solubility are given in grams of substance per 100 millilitres of water (g/(100 mL)), unless shown otherwise.
Metals are insoluble in water or organic solvents, unless they undergo a reaction with them. Typically, this is an oxidation reaction that robs the metal atoms of their itinerant electrons, destroying the metallic bonding. However metals are often readily soluble in each other while retaining the metallic character of their bonding.
Copper is a chemical element with the symbol Cu (from Latin: cuprum) and the atomic number of 29. It is easily recognisable, due to its distinct red-orange color.Copper also has a range of different organic and inorganic salts, having varying oxidation states ranging from (0,I) to (III).
Native copper is an uncombined form of copper that occurs as a natural mineral. Copper is one of the few metallic elements to occur in native form, although it most commonly occurs in oxidized states and mixed with other elements. Native copper was an important ore of copper in historic times and was used by pre-historic peoples.
Chalcopyrite is an exception to most copper bearing minerals. In contrast to the majority of copper minerals which can be leached at atmospheric conditions, such as through heap leaching, chalcopyrite is a refractory mineral that requires elevated temperatures as well as oxidizing conditions to release its copper into solution. [25]