Calcium

Kalisiomu jẹ́ kémíkàlì ìdá-ìpílè pẹ̀lú àmì ìdámò Ca àti ogún nọ́mbà átọ̀mù. Kalisiomu jẹ́́ alàwọ eléérú rírọ̀̀, ẹgbẹ́́ alkaline earth metal, ikarun ìdá-ìpílè tí ó wúwo jú nílé ayé.

Calcium, ₂₀Ca

Calcium
Ìhànsójú	Dull gray, silver
Ìwúwo átọ̀mù Ar, std(Ca)	40.078(4)
Calcium ní orí tábìlì àyè
Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson Mg ↑ Ca ↓ Sr potassium ← calcium → scandium
Nọ́mbà átọ̀mù (Z)	20
Ẹgbẹ́	group 2 (alkaline earth metals)
Àyè	àyè 4
Àdìpọ̀	Àdìpọ̀-s
Ẹ̀ka ẹ́límẹ́ntì	Alkaline earth metal
Ìtò ẹ̀lẹ́ktrọ́nù	[Ar] 4s2
Iye ẹ̀lẹ́ktrọ́nù lórí ìpele kọ̀ọ̀kan	2, 8, 8, 2
Àwọn ohun ìní ara
Ìfarahàn at STP	solid
Ìgbà ìyọ́	1115 K ​(842 °C, ​1548 °F)
Ígbà ìhó	1757 K ​(1484 °C, ​2703 °F)
Kíki (near r.t.)	1.55 g/cm3
when liquid (at m.p.)	1.378 g/cm3
Heat of fusion	8.54 kJ/mol
Heat of	154.7 kJ/mol
Molar heat capacity	25.929 J/(mol·K)
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	+1, +2 Àdàkọ:Infobox element/symbol-to-oxidation-state/comment
Electronegativity	Pauling scale: 1.00
energies	(more)
Atomic radius	empirical: 197 pm
Covalent radius	176±10 pm
Van der Waals radius	231 pm
Spectral lines of calcium
Other properties
Natural occurrence	primordial
Crystal structure	​(fcc)
Speed of sound thin rod	3810 m/s (at 20 °C)
Thermal expansion	22.3 µm/(m·K) (at 25 °C)
Thermal conductivity	201 W/(m·K)
Electrical resistivity	33.6 n Ω·m (at 20 °C)
Magnetic ordering	diamagnetic
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 Number	7440-70-2
Main isotopes of calcium
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct 40Ca 96.941% 40Ca is stable with 20 neutrons 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 β−β− ? 46Ti 47Ca syn 4.536 d β− 0.694, 1.99 47Sc γ 1.297 - 48Ca 0.187% >4×1019 y β−β− ? 48Ti