Biref Introduction of Cobalt
Cobalt, the element symbol Co, silver ferromagnetic white metal, the surface is slightly pale silver white, the fourth cycle in the periodic table, the Group VIII, the atomic number 27, atomic weight 58.9332, hexagonal close packed, common valence +2, +3. Cobalt is a shiny steel gray metal, relatively hard and brittle, ferromagnetic, magnetic disappeared when heated to 1150 ℃. Cobalt has valences of +2 and +3. It does not interact with water at room temperature and is stable in damp air. Cooled to CoO when heated in air to above 300 ° C, and burned into Co3O4 when whitened. Hydrogen reduction method made of fine metallic cobalt powder in the air can spontaneous combustion of cobalt oxide. Cobalt is an important raw material for the production of heat-resistant alloys, hard alloys, anti-corrosion alloys, magnetic alloys and various cobalt salts.