KAL-si-em
Calcium is an Alkaline earth metal in Group 2 of the periodic table that is the fifth most abundant element in the earths crust, forming compounds such as limestone and fossils. Calcium compounds have been known for years from the early days of sculpture using Calcium Carbonate (Limestone) but it was not until 1808 that Sir Humphry Davy isolated Calcium using electrolysis on a mixture of Calcium oxide and Mercuric Oxide. It has a wide variety of uses in the food industry as a supplement for the human body where it is important in nerve transmission and bone strength. A deficiency of calcium can lead to severe diseases such as osteoporosis and osteomalacia. In the human body Calcium and Vitamin D interact to improve the uptake of Calcium into bones. Calcium is also used in the paper industry as a bleach and in electrical insulators. It is a reactive metal so is not found naturally in the earth’s crust, instead existing as a compound most commonly Calcium Carbonate (Limestone). It is located in Group 2 as an Alkaline earth metal which is very reactive with water. It has a melting point of 842°c and a boiling point of 1484°c.
Sir Humphrey Davy
1808
Used by many forms of life to make shells and bones. Virtually no use for the pure metal, however two of its compounds are, lime (CaO) and gypsum (CaSO4), are in great demand by a number of industries.
Obtained from minerals like chalk, limestone & marble. Pure metal is produced by replacing the calcium in lime (calcium carbonate, CaCO3) with aluminium in hot, low pressure retorts.