Calcium twentieth element of the Periodic Table
The calcium metal belonging to the 2A family of the periodic table is an alkaline earth metal, silver white in color. It was first isolated by the British chemist Humphry Davy in 1808 by electrolysis. Because pure metal is highly reactive in contact with atmospheric air, it forms calcium oxide, which, following hydration, provides the calcium hydroxide base according to the reaction:Metallic calcium
Calcium is widely used in industry mainly in the form of carbonates and fluorides, as is commonly found in nature. Due to its high reactivity calcium is not found in pure form and for laboratory use must be isolated by chemical processes. It is used in construction under the name of Virgin Lime or Living Lime as a component in plaster. It is present in animal bones, dairy products and dissolved in groundwater.
It is used as an input for agricultural production in the form of calcium carbonate popularly known as limestone, which as an alkaline salt is used to correct soil pH, and as a fertilizer in the form of calcium sulfate and phosphate. It is also used in industry for syntheses of obtaining and purifying other metals.
Important Calcium Information:
Symbol: Ca
Oxidation Number: Ca² +
Atomic Mass: 40 u Atomic Number: 20 Melting Point: 842 ° C Boiling Point: 1484 ° C Electronic Configuration: 1s², 2s², 2p6,3s², 3p6,4s²
Natural forms: carbonates, bicarbonates and fluorides
Calcium in qualitative analysis: <> BR>
This element belongs to the fourth group of cations, and is reacted with Ammonium Carbonate, which when added to a solution containing calcium ions occurs the formation of a white precipitate of calcium carbonate, and with the addition of sulfate ions, it is obtained. A white precipitate of calcium sulfate and compounds containing the element gives a yellowish red color to the bunsen flame.
Bibliography:
http://wikienergia.com/~edp/index.php?title=C%C3%A1cio
Vogel, Arthur Israel, 1905-Qualitative Analytical Chemistry /
Arthur I. Vogel; [translation by Antonio Gimeno da] 5. ed.
rev. by G. Svehla.- São Paulo: Mestre Jou, 1981