One Network. One Network allows you to stay in touch with your friends and family on your airtel number while roaming in these airtel operators: Burkina Faso, Chad, Congo B, DRC, Gabon, Ghana, Kenya, Madagascar, Malawi, Nigeria, Niger, Sierra Leone, Tanzania, Zambia, Seychelles and Rwanda.This service allows you:nternational Roaming. At airtel, we understand your travel needs, thatâs why we make sure you stay in touch with friends and family by offering the most affordable and excellent roaming service coupled with the fastest internet speed. You can currently roam in over 356 networks in 147 countries worldwide.
History and Uses: Although calcium is the fifth most abundant element in the earth's crust, it is never found free in nature since it easily forms compounds by reacting with oxygen and water. Metallic calcium was first isolated by Sir Humphry Davy in 1808 through the electrolysis of a mixture of lime (CaO) and mercuric oxide (HgO).
Calcium is a moderately active element. It reacts readily with oxygen to form calcium oxide (CaO): Calcium reacts with the halogensâ fluorine, chlorine, bromine, iodine, and astatine, The halogens are the elements that make up Group 17 (VIIA) of the periodic table.ilk is a good source of calcium. The body uses calcium in a compound known as hydroxyapatite (Ca 10 (PO 4) 6 (OH) 2) to make bones and teeth hard and resistant to wear. Calcium has many other important functions in the human body.