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Calcium

Calcium is a chemical element; it has symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to its heavier homologues strontium and barium. It is the fifth most abundant element in Earth's crust, and the third…

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40Ca
96.9%
41Ca
trace
42Ca
0.647%
43Ca
0.135%
44Ca
2.09%
45Ca
synth

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Overview

Characteristics

History

Occurrence and production

Applications

Food sources

Biological and pathological role

Bibliography

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Map overview Semantic statistics

Calcium

Nodes277
Edges276
Triples215
Avg. degree1.99
Density0.00722
Components1

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Calcium

Top relations

related to Occurrence and production · 24
Calcium → Among, At, Bahamas, Ca5, CaF2, Canada, CaSO4, China, Cl, Corals, Earth's, Florida Keys, France, Iceland, In, It, Minerals, OH, PO4, Red Sea
related to Chemical properties · 15
Calcium → All, Besides, Bulk, Ca, CaCO3, CaO, CaO2, CaSO4, For, It, Like, O2, OH, The, When
related to history · 14
Calcium → About, BC, CaCO3, CaSO4, Giza, Great Pyramid, Khafajah, Latin, Lime, Mesopotamia, Romans, The, This, Tutankhamun
related to Bibliography · 10
Calcium → Calcium Alloys, Hluchan, Industrial Chemistry, ISBN, Kenneth, Pomerantz, Stephen, Ullmann's Encyclopedia, Weinheim, Wiley-VCH
related to Food sources · 10
Calcium → Because, EFSA, European Food Safety Authority, Foods, From, Institute, IOM, Medicine, UL, ULs
related to Classification · 9
Calcium → Ar, Ca, Ca2, Hence, Hypothetical, Like, MX, MX2, This
related to Geochemical cycling · 9
Calcium → Ca2, CaCO3, CO2, DIC, Dissolved CO2, HCO, In, The, These
is a · 8
Calcium → chemical element, fifth most abundant element in the Earth's crust, first, mixture of five stable isotopes, most abundant metal and the fifth-most abundant element in the human body, only element with two primordial doubly magic isotopes, poorer conductor of electricity than copper or aluminium by volume, reactive metal that forms a dark oxide-nitride layer when exposed to air
related to Abnormal serum levels · 7
Calcium → All, Chronic, Conversely, Excess, However, PTH, Symptoms
Ionisation energies · 4
Calcium → (more), 1st: 589.8 kJ/mol, 2nd: 1145.4 kJ/mol, 3rd: 4912.4 kJ/mol

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Important terminology

metal used also isotopes element strontium lime bone compounds barium aluminium stable chemical magnesium 48ca high ca2 40ca carbon oxygen

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Calcium40Ca96.9%1.00infobox
Calcium41Catrace1.00infobox
Calcium42Ca0.647%1.00infobox
Calcium43Ca0.135%1.00infobox
Calcium44Ca2.09%1.00infobox
Calcium45Casynth1.00infobox
Calcium46Ca0.004%1.00infobox
Calcium47Casynth1.00infobox
Calcium48Ca0.187%1.00infobox
CalciumAppearancedull gray, silver; with a pale yellow tint1.00infobox
Calciumat T (K)8641.00infobox
CalciumAtomic number (Z)201.00infobox
CalciumAtomic radiusempirical: 197 pm1.00infobox
CalciumBlocks-block1.00infobox
CalciumBoiling point1757 K ​(1484 °C, ​2703 °F)1.00infobox
CalciumBrinell hardness170–416 MPa1.00infobox
CalciumBulk modulus17 GPa1.00infobox
CalciumCAS Number7440-70-21.00infobox
CalciumCovalent radius176±10 pm1.00infobox
CalciumCrystal structure​face-centred cubic (fcc) (cF4)1.00infobox
CalciumDensity (at 20° C)1.526 g/cm31.00infobox
CalciumDiscovery and first isolationHumphry Davy (1808)1.00infobox
CalciumElectrical resistivity33.6 nΩ⋅m (at 20 °C)1.00infobox
CalciumElectron configuration[Ar] 4s21.00infobox
CalciumElectronegativityPauling scale: 1.001.00infobox
CalciumElectrons per shell2, 8, 8, 21.00infobox
CalciumGroupgroup 2 (alkaline earth metals)1.00infobox
CalciumHeat of fusion8.54 kJ/mol1.00infobox
CalciumHeat of vaporisation154.7 kJ/mol1.00infobox
CalciumIonisation energies1st: 589.8 kJ/mol1.00infobox

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