Plantilya:Infobox calcium

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Calcium
20Ca
Mg

Ca

Sr
potassiumcalciumscandium
Appearance
dull gray, silver


Spectral lines of calcium
General properties
Name, simbolo, kaiphan calcium, Ca, 20
Pronunciation Plantilya:IPAc-en Plantilya:Respell
Element category puthaw
Group, period, block 24, s
Standard atomic weight 40.078(4)
Electron configuration [Ar] 4s2
2, 8, 8, 2
Electron shells of calcium (2, 8, 8, 2)
History
Discovery Humphry Davy (1808)
First isolation Humphry Davy (1808)
Physical properties
Phase magahi
Density (near r.t.) 1.55 g·cm−3
Liquid density at m.p. 1.378 g·cm−3
Melting point 1115 K, 842 °C, 1548 °F
Boiling point 1757 K, 1484 °C, 2703 °F
Heat of fusion 8.54 kJ·mol−1
Heat of vaporization 154.7 kJ·mol−1
Molar heat capacity 25.929 J·mol−1·K−1
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 864 956 1071 1227 1443 1755
Atomic properties
Oxidation states +2, +1[1]
(strongly basic oxide)
Electronegativity 1.00 (Pauling scale)
Ionization energies
(more)
1st: 589.8 kJ·mol−1
2nd: 1145.4 kJ·mol−1
3rd: 4912.4 kJ·mol−1
Atomic radius 197 pm
Covalent radius 176±10 pm
Van der Waals radius 231 pm
Miscellanea
Crystal structure face-centered cubic
Calcium has a face-centered cubic crystal structure
Magnetic ordering diamagnetic
Electrical resistivity (20 °C) 33.6 nΩ·m
Thermal conductivity 201 W·m−1·K−1
Thermal expansion (25 °C) 22.3 µm·m−1·K−1
Speed of sound (thin rod) (20 °C) 3810 m·s−1
Young's modulus 20 GPa
Shear modulus 7.4 GPa
Bulk modulus 17 GPa
Poisson ratio 0.31
Mohs hardness 1.75
Brinell hardness 167 MPa
CAS registry number 7440-70-2
Most stable isotopes
Main article: Isotopes of calcium
iso NA half-life DM DE (MeV) DP
40Ca 96.941% >5.9×1021 y β+β+ 0.194 40Ar
41Ca trace 1.03×105 y ε - 41K
42Ca 0.647% 42Ca is stable with 22 neutrons
43Ca 0.135% 43Ca is stable with 23 neutrons
44Ca 2.086% 44Ca is stable with 24 neutrons
45Ca syn 162.7 d β 0.258 45Sc
46Ca 0.004% >2.8×1015 y ββ 0.988 46Ti
47Ca syn 4.536 d β 0.694, 1.99 47Sc
γ 1.297 -
48Ca 0.187% 4.3×1019 y ββ 4.274 48Ti
β
(not observed)
0.0058 48Sc
t  h  u
· r

Plantilya:Template reference list

  1. Krieck, Sven; Görls, Helmar; Westerhausen, Matthias (2010). "Mechanistic Elucidation of the Formation of the Inverse Ca(I) Sandwich Complex [(thf)3Ca(μ-C6H3-1,3,5-Ph3)Ca(thf)3] and Stability of Aryl-Substituted Phenylcalcium Complexes". Journal of the American Chemical Society 132 (35): 100818110534020. doi:10.1021/ja105534w. PMID 20718434.