Kalsium

Kemiallinen merkki: Ca
Järjestysluku: 20
Kategoria: maa-alkalimetallit
Ryhmä: 2
Jakso: 4
Lohko: s
Moolimassa: 40,078 g/mol
Elektronia kuorilla: 2, 8, 8, 2
CAS-numero: 7440-70-2
Olomuoto: kiinteä
Tiheys: 1,55 kg/l (lähellä huoneenlämpöä)
Sulamispiste: 1115 K (842 °C, 1548 °F)
Kiehumispiste: 1757 K (1484 °C, 2703 °F)
Kiderakenne: face centered cubic
Hapetusluvut: 2
Elektronegatiivisuus: 1,00 (Pauling-asteikko)
Nimen alkuperä: calisis
Nimen tarkoitus: lime, as the Ancient Romans prepared lime as calcium oxide
Faktoja:
- is essential for living organisms, particularly in cell physiology
- is not naturally found in its elemental state, but occurs most commonly in sedimentary rocks in the minerals calcite, dolomite and gypsum
- is somewhat difficult to ignite, unlike magnesium, but when lit, the metal burns in air with a brilliant high-intensity red light
- calcium metal reacts with water, evolving hydrogen gas at a rate rapid enough to be noticeable