Barium

Báríọ́mù (pípè /ˈbɛəriəm/, BAIR-ee-əm) jẹ́ ìpilẹ̀ṣẹ̀ kẹ́míkà. Ó ní àmì-ìdánimọ̀ Bá, nọ́mbà átọ́ọ́mù rẹ̀ jẹ́ mẹ́rìndínlọ́gọ́ta (56), nítorí òun ni ìpilẹ̀ṣẹ̀ karùn ún ní ipò kejì nínú kẹ́míkà atọ́ọ́mù.

Barium, ₅₆Ba

Barium
Pípè	/ˈbɛəriəm/ ​(BAIR-ee-əm)
Ìhànsójú	silvery gray
Ìwúwo átọ̀mù Ar, std(Ba)	137.327(7)
Barium 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 Sr ↑ Ba ↓ Ra caesium ← barium → lanthanum
Nọ́mbà átọ̀mù (Z)	56
Ẹgbẹ́	group 2 (alkaline earth metals)
Àyè	àyè 6
Àdìpọ̀	Àdìpọ̀-s
Ẹ̀ka ẹ́límẹ́ntì	Alkaline earth metal
Ìtò ẹ̀lẹ́ktrọ́nù	[Xe] 6s2
Iye ẹ̀lẹ́ktrọ́nù lórí ìpele kọ̀ọ̀kan	2, 8, 18, 18, 8, 2
Àwọn ohun ìní ara
Ìfarahàn at STP	solid
Ìgbà ìyọ́	1000 K ​(727 °C, ​1341 °F)
Ígbà ìhó	2170 K ​(1897 °C, ​3447 °F)
Kíki (near r.t.)	3.51 g/cm3
when liquid (at m.p.)	3.338 g/cm3
Heat of fusion	7.12 kJ/mol
Heat of	140.3 kJ/mol
Molar heat capacity	28.07 J/(mol·K)
pressure P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 911 1038 1185 1388 1686 2170
Atomic properties
Oxidation states	+1, +2 Àdàkọ:Infobox element/symbol-to-oxidation-state/comment
Electronegativity	Pauling scale: 0.89
Atomic radius	empirical: 222 pm
Covalent radius	215±11 pm
Van der Waals radius	268 pm
Color lines in a spectral range Spectral lines of barium
Other properties
Natural occurrence	primordial
Crystal structure	​(bcc)
Speed of sound thin rod	1620 m/s (at 20 °C)
Thermal expansion	20.6 µm/(m·K) (at 25 °C)
Thermal conductivity	18.4 W/(m·K)
Electrical resistivity	332 n Ω·m (at 20 °C)
Magnetic ordering	paramagnetic
Young's modulus	13 GPa
Shear modulus	4.9 GPa
Bulk modulus	9.6 GPa
Mohs hardness	1.25
CAS Number	7440-39-3
Main isotopes of barium
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct 130Ba 0.106% 130Ba is stable with 74 neutrons 132Ba 0.101% 132Ba is stable with 76 neutrons 133Ba syn 10.51 y ε 0.517 133Cs 134Ba 2.417% 134Ba is stable with 78 neutrons 135Ba 6.592% 135Ba is stable with 79 neutrons 136Ba 7.854% 136Ba is stable with 80 neutrons 137Ba 11.23% 137Ba is stable with 81 neutrons 138Ba 71.7% 138Ba is stable with 82 neutrons