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Calcium • Alkaline Earth Metal

Primary XPS region: Ca2p
Overlapping regions: Mg KLL
Binding energies of common chemical states:

Chemical state Binding energy Ca2p3/2 / eV
CaCO3 347.2
Ca3(PO4)2 347.4

Charge referenced to adventitious C1s peak at 284.8eV

Experimental Information

Interpretation of XPS spectra

General comments

crystal structureAbout This Element

Symbol: Ca
Date of Discovery: 1808
Name Origin: Latin calcis
Appearance: silvery
Discoverer: Sir Humphrey Davy
Obtained From: chalk, limestone, marble

Melting Point: 1112.15 K
Boiling Point: 1757.15 K
Density[kg/m3]: 1550
Molar Volume: 26.20 × 10-6 m3/mol
Neutrons: 20
Shell Structure: 2,8,8,2
Electron Configuration: [Ar]4s2
Oxidation State: 2
Protons/Electrons: 20
Crystal Structure: cubic face centered

H. Davy first isolated calcium in 1808. It is the fifth most abundant element in the earth’s crust and is an important component for living organisms on the cellular level, as well as for the formation bones and teeth in higher organisms. Besides being an essential element for living things, calcium is used as a reducing agent in the extraction of thorium, zirconium and uranium, and is an alloying agent in the production of aluminum alloys. Chemical refinery processes commonly use quicklime (CaO), which is also an important component in cement. Water dissolving calcium compounds in the earth, such as limestone, form caves – including stalactites and stalagmites – and are the major cause of hard water.


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