Cobalt is a transition metal, one of the elements that occurs in the middle of the periodic table, between Groups 2 and 13. It is located between iron and nickel, with whom it shares many common properties. Cobalt's atomic number is 27, its atomic mass is 58.9332, and its chemical symbol is Co.

Properties

Cobalt is a hard, gray metal that looks much like iron and nickel. It is ductile, but only moderately malleable. Cobalt is one of three naturally occurring magnetic elements, the other two being iron and nickel. The melting point of cobalt is 2,719°F (1,493°C), its boiling point is about 5,250°F (2,900°C), and its density is 8.9 grams per cubic centimeter. Cobalt is a moderately reactive element that combines slowly with oxygen in the air. It does not react with water at room temperature, but it does react with most acids to produce hydrogen.

Occurrence and Extraction