Barium (Ba)

Barium is the 56th element in the periodic table and has a symbol of Ba and atomic number of 56. It has an atomic weight of 137.327 and a mass number of 138. Barium has fifty-six protons and eighty-two neutrons in its nucleus, and fifty-six electrons in six shells. It is located in group two, period six and block s of the periodic table. Silvery-white reactive element, belonging to group 2 of the periodic table. Soluble barium compounds are extremely poisonous. Identified in 1774 by Karl Scheele and extracted in 1808 by Humphry Davy.

Atomic Number	56
Atomic Weight	137.327
Mass Number	138

Group	2
Period	6
Block	s

Protons	56 p⁺
Neutrons	82 n⁰
Electrons	56 e^-

Properties

Physical Properties
Atomic Radius	215 pm 293 pm
Molar Volume	39 cm³/mol
Covalent Radius	196 pm 161 pm 149 pm 210 pm 215 pm
Metallic Radius	198 pm 222 pm
Ionic Radius	135 pm 138 pm 142 pm 147 pm 152 pm 157 pm 161 pm
Crystal Radius	149 pm 152 pm 156 pm 161 pm 166 pm 171 pm 175 pm
Van der Waals Radius	270 pm 268 pm 307 pm 268 pm 370.3 pm
Density	3.62 g/cm³ 3,338 kg/m³
Energy
Proton Affinity
Electron Affinity	0.14462 eV/particle
Ionization Energy	5.211664 eV/particle 10.003826 eV/particle 35.84 eV/particle 47.03 eV/particle 58 eV/particle 71 eV/particle 86 eV/particle 101 eV/particle 130.53 eV/particle 146.52 eV/particle 241 eV/particle 267.1 eV/particle 296 eV/particle 325 eV/particle 354 eV/particle 390 eV/particle 422 eV/particle 455 eV/particle 488 eV/particle 520 eV/particle 646 eV/particle 679 eV/particle 717 eV/particle 752 eV/particle 809 eV/particle 846 eV/particle 935 eV/particle 976.6 eV/particle 1,695 eV/particle 1,776 eV/particle 1,864 eV/particle 1,958 eV/particle 2,047 eV/particle 2,142 eV/particle 2,256 eV/particle 2,349 eV/particle 2,452 eV/particle 2,547 eV/particle 2,814 eV/particle 2,901 eV/particle 2,994 eV/particle 3,081 eV/particle 3,266 eV/particle 3,363 eV/particle 3,550 eV/particle 3,640 eV/particle 8,326 eV/particle 8,565 eV/particle 8,831 eV/particle 9,077 eV/particle 9,739 eV/particle 10,023 eV/particle 10,376 eV/particle 10,616.42 eV/particle 43,485.364 eV/particle 44,561.47 eV/particle

Heat of Vaporization	142 kJ/mol
Heat of Fusion	7.66 kJ/mol
Heat of Formation	179.1 kJ/mol
Electrons
Electron Shells	2, 8, 18, 18, 8, 2

Valence Electrons	2

Electron Configuration	[Xe] 6s²

Oxidation States	1, 2
Electronegativity	5.211 eV/particle 0.1586786 0.89
Electrophilicity	0.7077543210759566 eV/particle
Phases
Phase	Solid
Gas Phase
Boiling Point	2,118.15 K
Melting Point	1,000.15 K
Critical Pressure
Critical Temperature
Triple Point
Visual
Barium is a Silver. Ba has a CPK of #ffa500, Jmol of #00c900, and MOLCAS GV of #00c900.
Color	Silver #ffa500 #00c900 #00c900
Appearance
Refractive Index
Thermodynamic Properties
Thermal Conductivity
Thermal Expansion	0.0000206 1/K
Molar Heat Capacity	28.07 J/(mol K)
Specific Heat Capacity	0.204 J/(g⋅K)
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
Type	Conductor
Electrical Conductivity	2.9 MS/m
Electrical Resistivity	0.00000035 m Ω
Superconducting Point
Magnetism
Type	paramagnetic
Magnetic Susceptibility (Mass)	0.0000000113 m³/Kg
Magnetic Susceptibility (Molar)	0.000000001552 m³/mol
Magnetic Susceptibility (Volume)	0.00003966
Magnetic Ordering
Curie Point
Neel Point
Structure
The Crystal Structure of Barium is BCC. The lattice constant of Ba is 5.02 Å. The lattice angles of Element 56 are π/2, π/2, π/2.
Crystal Structure	Body Centered Cubic (BCC)
Lattice Constant	5.02 Å
Lattice Angles	π/2, π/2, π/2
Mechanical Properties
Barium has a Mohs hardness of 1.25 MPa. The Bulk Modulus of Ba is 9.6 GPa. The Shear Modulus of Element 56 is 4.9 GPa. The Young Modulus of Barium (Ba) is 13 GPa. The Speed of Sound of Barium is 1620 m/s.
Hardness	1.25 MPa
Bulk Modulus	9.6 GPa
Shear Modulus	4.9 GPa
Young Modulus	13 GPa
Poisson Ratio
Speed of Sound	1,620 m/s
Classification
The CAS Group of Barium is IIA. The IUPAC Group of Ba is IIA. The Glawe Number of Element 56 is 14. The Mendeleev Number of Barium (Ba) is 9. The Pettifor Number of Barium is 14. The Geochemical Class of Ba is alkaline earth metal. The Goldschmidt Class of Element 56 is litophile.
Category	Alkaline earth metals, Alkaline earth metals
CAS Group	IIA
IUPAC Group	IIA
Glawe Number	14
Mendeleev Number	9
Pettifor Number	14
Geochemical Class	alkaline earth metal
Goldschmidt Class	litophile
Other
The Dipole Polarizability of Barium is 272 plus or minus 10 a₀. Ba has a C6 Dispersion Coefficient (GB) of 5540 a₀. The Allotropes of Element 56 is . The Neutron Cross Section of Barium (Ba) is 1.3. The Neutron Mass Absorption of Barium is 0.00027. The Quantum Numbers of Ba is 1S0. The Space Group of Element 56 is 229 (Im_3m).
Gas Basicity
Dipole Polarizability	272 ± 10 a₀
C6 Dispersion Coefficient	5,540 a₀
Allotropes
Neutron Cross Section	1.3
Neutron Mass Absorption	0.00027
Quantum Numbers	1S0
Space Group	229 (Im_3m)

Isotopes of Barium

Stable Isotopes	7
Unstable Isotopes	35
Radioactive Isotopes	35

¹¹³Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	112.95737 ± 0.000322 Da
Mass Number	113
G-Factor
Half Life
Spin	5/2
Quadrupole Moment
Discovery Year
Parity	+

¹¹³Ba Decay Modes

Decay Mode	Intensity
p (proton emission)	%
α (α emission)	%

¹¹⁴Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	113.950718489 ± 0.000110227 Da
Mass Number	114
G-Factor	0
Half Life	460 ± 125 ms
Spin	0
Quadrupole Moment	0
Discovery Year	1995
Parity	+

¹¹⁴Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	20%
α (α emission)	0.9%
12C	0.0034%

¹¹⁵Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	114.947482 ± 0.000215 Da
Mass Number	115
G-Factor
Half Life	450 ± 50 ms
Spin	5/2
Quadrupole Moment
Discovery Year	1997
Parity	+

¹¹⁵Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	15%

¹¹⁶Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	115.941621 ± 0.000215 Da
Mass Number	116
G-Factor	0
Half Life	1.3 ± 0.2 s
Spin	0
Quadrupole Moment	0
Discovery Year	1997
Parity	+

¹¹⁶Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	3%

¹¹⁷Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	116.938316403 ± 0.000268749 Da
Mass Number	117
G-Factor
Half Life	1.75 ± 0.07 s
Spin	3/2
Quadrupole Moment
Discovery Year	1977
Parity	+

¹¹⁷Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	13%
β⁺α (β⁺-delayed α emission)	0.024%

¹¹⁸Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	117.933226 ± 0.000215 Da
Mass Number	118
G-Factor	0
Half Life	5.2 ± 0.2 s
Spin	0
Quadrupole Moment	0
Discovery Year	1997
Parity	+

¹¹⁸Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹¹⁹Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	118.930659683 ± 0.000214997 Da
Mass Number	119
G-Factor
Half Life	5.4 ± 0.3 s
Spin	5/2
Quadrupole Moment
Discovery Year	1974
Parity	+

¹¹⁹Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	25%

¹²⁰Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	119.926044997 ± 0.000322241 Da
Mass Number	120
G-Factor	0
Half Life	24 ± 2 s
Spin	0
Quadrupole Moment	0
Discovery Year	1974
Parity	+

¹²⁰Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹²¹Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	120.924052286 ± 0.000152333 Da
Mass Number	121
G-Factor	0.264 ± 0.0004
Half Life	29.7 ± 1.5 s
Spin	5/2
Quadrupole Moment	1.89 ± 0.13
Discovery Year	1975
Parity	+

¹²¹Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	0.02%

¹²²Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	121.919904 ± 0.00003 Da
Mass Number	122
G-Factor	0
Half Life	1.95 ± 0.15 m
Spin	0
Quadrupole Moment	0
Discovery Year	1974
Parity	+

¹²²Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹²³Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	122.91878106 ± 0.000013 Da
Mass Number	123
G-Factor	-0.272 ± 0.0004
Half Life	2.7 ± 0.4 m
Spin	5/2
Quadrupole Moment	1.57 ± 0.13
Discovery Year	1962
Parity	+

¹²³Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹²⁴Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	123.915093627 ± 0.000013416 Da
Mass Number	124
G-Factor	0
Half Life	11 ± 0.5 m
Spin	0
Quadrupole Moment	0
Discovery Year	1967
Parity	+

¹²⁴Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹²⁵Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	124.91447184 ± 0.0000118 Da
Mass Number	125
G-Factor	0.354 ± 0.024
Half Life	3.3 ± 0.3 m
Spin	1/2
Quadrupole Moment	0
Discovery Year	1968
Parity	+

¹²⁵Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹²⁶Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	125.911250202 ± 0.000013416 Da
Mass Number	126
G-Factor	0
Half Life	100 ± 2 m
Spin	0
Quadrupole Moment	0
Discovery Year	1954
Parity	+

¹²⁶Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹²⁷Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	126.911091272 ± 0.000012192 Da
Mass Number	127
G-Factor	0.1668 ± 0.002
Half Life	12.7 ± 0.4 m
Spin	1/2
Quadrupole Moment	0
Discovery Year	1952
Parity	+

¹²⁷Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹²⁸Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	127.908352446 ± 0.000001728 Da
Mass Number	128
G-Factor	0
Half Life	2.43 ± 0.05 d
Spin	0
Quadrupole Moment	0
Discovery Year	1950
Parity	+

¹²⁸Ba Decay Modes

Decay Mode	Intensity
ϵ (electron capture)	100%

¹²⁹Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	128.908683409 ± 0.000011276 Da
Mass Number	129
G-Factor
Half Life	2.23 ± 0.11 h
Spin	1/2
Quadrupole Moment	0
Discovery Year	1950
Parity	+

¹²⁹Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹³⁰Ba

Abundance	0.11 ± 0.01
Relative Atomic Mass	129.906326002 ± 0.000000308 Da
Mass Number	130
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1936
Parity	+

¹³⁰Ba Decay Modes

Decay Mode	Intensity
2β⁺ (double β⁺ decay)	%

¹³¹Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	130.906946315 ± 0.000000445 Da
Mass Number	131
G-Factor	1.4166 ± 0.0004
Half Life	11.52 ± 0.01 d
Spin	1/2
Quadrupole Moment	0
Discovery Year	1947
Parity	+

¹³¹Ba Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹³²Ba

Abundance	0.1 ± 0.01
Relative Atomic Mass	131.905061231 ± 0.00000113 Da
Mass Number	132
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1936
Parity	+

¹³²Ba Decay Modes

Decay Mode	Intensity
2β⁺ (double β⁺ decay)	%

¹³³Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	132.906007443 ± 0.000001065 Da
Mass Number	133
G-Factor	1.5438 ± 0.0004
Half Life	10.5379 ± 0.0016 y
Spin	1/2
Quadrupole Moment	0
Discovery Year	1941
Parity	+

¹³³Ba Decay Modes

Decay Mode	Intensity
ϵ (electron capture)	100%

¹³⁴Ba

Abundance	2.42 ± 0.15
Relative Atomic Mass	133.904508249 ± 0.000000269 Da
Mass Number	134
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1936
Parity	+

¹³⁵Ba

Abundance	6.59 ± 0.1
Relative Atomic Mass	134.905688447 ± 0.000000263 Da
Mass Number	135
G-Factor	0.55873333333333 ± 0.00013333333333333
Half Life
Spin	3/2
Quadrupole Moment	0.153 ± 0.002
Discovery Year	1932
Parity	+

¹³⁶Ba

Abundance	7.85 ± 0.24
Relative Atomic Mass	135.9045758 ± 0.000000262 Da
Mass Number	136
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1932
Parity	+

¹³⁷Ba

Abundance	11.23 ± 0.23
Relative Atomic Mass	136.905827207 ± 0.000000266 Da
Mass Number	137
G-Factor	0.625 ± 0.00013333333333333
Half Life
Spin	3/2
Quadrupole Moment	0.236 ± 0.003
Discovery Year	1932
Parity	+

¹³⁸Ba

Abundance	71.7 ± 0.29
Relative Atomic Mass	137.905247059 ± 0.000000267 Da
Mass Number	138
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1925
Parity	+

¹³⁹Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	138.908841164 ± 0.000000271 Da
Mass Number	139
G-Factor	-0.278 ± 0.0014285714285714
Half Life	82.93 ± 0.09 m
Spin	7/2
Quadrupole Moment	-0.552 ± 0.013
Discovery Year	1937
Parity	-

¹³⁹Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁴⁰Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	139.910608231 ± 0.00000848 Da
Mass Number	140
G-Factor	0
Half Life	12.7534 ± 0.0021 d
Spin	0
Quadrupole Moment	0
Discovery Year	1939
Parity	+

¹⁴⁰Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁴¹Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	140.914403653 ± 0.000005709 Da
Mass Number	141
G-Factor	-0.22466666666667 ± 0.0033333333333333
Half Life	18.27 ± 0.07 m
Spin	3/2
Quadrupole Moment	0.437 ± 0.01
Discovery Year	1945
Parity	-

¹⁴¹Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁴²Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	141.916432904 ± 0.000006355 Da
Mass Number	142
G-Factor	0
Half Life	10.6 ± 0.2 m
Spin	0
Quadrupole Moment	0
Discovery Year	1959
Parity	+

¹⁴²Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁴³Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	142.920625149 ± 0.000007253 Da
Mass Number	143
G-Factor	0.1772 ± 0.0044
Half Life	14.5 ± 0.3 s
Spin	5/2
Quadrupole Moment	-0.85 ± 0.02
Discovery Year	1962
Parity	-

¹⁴³Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁴⁴Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	143.922954821 ± 0.000007661 Da
Mass Number	144
G-Factor	0
Half Life	11.73 ± 0.08 s
Spin	0
Quadrupole Moment	0
Discovery Year	1967
Parity	+

¹⁴⁴Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁴⁵Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	144.9275184 ± 0.0000091 Da
Mass Number	145
G-Factor	-0.114 ± 0.0028
Half Life	4.31 ± 0.16 s
Spin	5/2
Quadrupole Moment	1.18 ± 0.02
Discovery Year	1974
Parity	-

¹⁴⁵Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁴⁶Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	145.9303632 ± 0.0000019 Da
Mass Number	146
G-Factor	0
Half Life	2.15 ± 0.04 s
Spin	0
Quadrupole Moment	0
Discovery Year	1970
Parity	+

¹⁴⁶Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁴⁷Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	146.9353039 ± 0.0000212 Da
Mass Number	147
G-Factor
Half Life	893 ± 1 ms
Spin	5/2
Quadrupole Moment
Discovery Year	1978
Parity	-

¹⁴⁷Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	0.07%

¹⁴⁸Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	147.938223 ± 0.0000016 Da
Mass Number	148
G-Factor	0
Half Life	620 ± 5 ms
Spin	0
Quadrupole Moment	0
Discovery Year	1979
Parity	+

¹⁴⁸Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	0.4%

¹⁴⁹Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	148.943284 ± 0.0000027 Da
Mass Number	149
G-Factor
Half Life	349 ± 4 ms
Spin	3/2
Quadrupole Moment
Discovery Year	1993
Parity	-

¹⁴⁹Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	3.9%

¹⁵⁰Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	149.9464411 ± 0.0000061 Da
Mass Number	150
G-Factor	0
Half Life	258 ± 5 ms
Spin	0
Quadrupole Moment	0
Discovery Year	1994
Parity	+

¹⁵⁰Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	1%

¹⁵¹Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	150.951755 ± 0.000429 Da
Mass Number	151
G-Factor
Half Life	167 ± 5 ms
Spin	3/2
Quadrupole Moment
Discovery Year	1994
Parity	-

¹⁵¹Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	%

¹⁵²Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	151.95533 ± 0.000429 Da
Mass Number	152
G-Factor	0
Half Life	139 ± 8 ms
Spin	0
Quadrupole Moment	0
Discovery Year	2010
Parity	+

¹⁵²Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	%

¹⁵³Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	152.960848 ± 0.000429 Da
Mass Number	153
G-Factor
Half Life	113 ± 39 ms
Spin	5/2
Quadrupole Moment
Discovery Year	2016
Parity	-

¹⁵³Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	%
2n (2-neutron emission)	%

¹⁵⁴Ba

Abundance	Radioactive ☢️
Relative Atomic Mass	153.964659 ± 0.000537 Da
Mass Number	154
G-Factor	0
Half Life	53 ± 48 ms
Spin	0
Quadrupole Moment	0
Discovery Year	2017
Parity	+

¹⁵⁴Ba Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

History

Barium was identified as a new element in 1774 by Carl Wilhelm Scheele. Barium was first isolated by electrolysis of molten barium salts in 1808, by Sir Humphry Davy in England. Robert Bunsen and Augustus Matthiessen obtained pure barium by electrolysis of a molten mixture of barium chloride and ammonium chloride. From the Greek word barys, heavy

Discoverers	Sir Humphrey Davy
Discovery Location	England
Discovery Year	1808
Etymology (Name Origin)	Greek: barys (heavy or dense).
Pronunciation	BAR-i-em (English)

Water-soluble barium compounds are poisonous

At low doses, barium acts as a muscle stimulant

Uses

Barium is used as a flashed getter in vacuum tubes to remove the last traces of gases. It is often used in barium-nickel alloys for spark plug wire. Barium sulfate is important to the petroleum industry as a drilling fluid in oil and gas wells. Barium is also used in medicine to detect abnormalities in the digestive system. Barite, or barium sulfate (BaSO4), when ground is used as a filter for rubber, plastics, and resins. It is insoluable in water and so is used in X-rays of the digestive system. Barium nitrate, Ba(NO3)2, burns brilliant green and is used in fireworks.

Sources

Found in barytine (BaSO4) and witherite (BaCO3), never found in pure form due to its reactivity. Must be stored under kerosene to remain pure.

Abundance
Abundance in Earth's crust	425 mg/kg
Abundance in Oceans	0.013 mg/L
Abundance in Human Body	0.00003 %
Abundance in Meteor	0.00027 %
Abundance in Sun	0.000001 %
Abundance in Universe	0.000001 %

Nuclear Screening Constants

1	s	1.1139
2	p	4.1904
2	s	14.7532
3	d	13.9757
3	p	18.6836
3	s	18.8444
4	d	32.216
4	p	29.1968
4	s	28.08
5	p	41.1995
5	s	39.3805
6	s	48.425

Barium on ChemicalAid

Art & Architecture Thesaurus ID	300311585
Australian Educational Vocabulary ID	scot/2246
BNCF Thesaurus ID	31174
Biblioteca Nacional de España ID	XX540454
Bibliothèque nationale de France ID	12203013v
Brockhaus Enzyklopädie online ID	barium
CAB ID	18806
CA PROP 65 ID	barium
CAS Registry Number	7440-39-3
CPV Supplementary	AA32
ChEBI ID	32595
ChemSpider ID	4511436
Common Procurement Vocabulary	14765000
DSSTOX compound identifier	DTXCID80875617
DSSTox substance ID	DTXSID8023894
Den Store Danske ID	barium
DrugBank ID	12481
ECHA Substance Infocard ID	100.028.317
Encyclopædia Britannica Online ID	science/barium
Encyclopædia Universalis ID	baryum
Freebase ID	/m/025svml
French Vikidia ID	Baryum
GND ID	4140300-9
Gran Enciclopèdia Catalana ID	0006437
Great Russian Encyclopedia Online ID	862577
HSDB ID	4481
ICSC ID	1052
InChI	InChI=1S/Ba
InChIKey	DSAJWYNOEDNPEQ-UHFFFAOYSA-N
KBpedia ID	Barium
Krugosvet article	nauka_i_tehnika/himiya/BARI.html
LEM ID	LEM201001269
Library of Congress authority ID	sh85011853
MeSH descriptor ID	D001464
NALT ID	6419
NDL Authority ID	00560541
NE.se ID	barium
NKCR AUT ID	ph163873
Namuwiki ID	바륨
National Library of Israel J9U ID	987007283148305171
National Library of Latvia ID	000302070
OmegaWiki Defined Meaning	310
OpenAlex ID	C542576722
PM20 ware ID	142042
PSH ID	5754
PubChem CID	5355457
Quora topic ID	Barium
RxNorm ID	1311067
Römpp online ID	RD-02-00240
Store medisinske leksikon ID	barium
Store norske leksikon ID	barium
Treccani ID	bario
UK Archival Thesaurus ID	f2/mt225/4347/7670
UK Parliament thesaurus ID	8545
UNII	24GP945V5T
USGS Thesaurus ID	1403
WordNet 3.1 Synset ID	14654176-n
YSO ID	39159
ZVG number	8420

Barium (Ba)

Properties

Isotopes of Barium

113Ba

113Ba Decay Modes

114Ba

114Ba Decay Modes

115Ba

115Ba Decay Modes

116Ba

116Ba Decay Modes

117Ba

117Ba Decay Modes

118Ba

118Ba Decay Modes

119Ba

119Ba Decay Modes

120Ba

120Ba Decay Modes

121Ba

121Ba Decay Modes

122Ba

122Ba Decay Modes

123Ba

123Ba Decay Modes

124Ba

124Ba Decay Modes

125Ba

125Ba Decay Modes

126Ba

126Ba Decay Modes

127Ba

127Ba Decay Modes

128Ba

128Ba Decay Modes

129Ba

129Ba Decay Modes

130Ba

130Ba Decay Modes

131Ba

131Ba Decay Modes

132Ba

132Ba Decay Modes

133Ba

133Ba Decay Modes

134Ba

135Ba

136Ba

137Ba

138Ba

139Ba

139Ba Decay Modes

140Ba

140Ba Decay Modes

141Ba

141Ba Decay Modes

142Ba

142Ba Decay Modes

143Ba

143Ba Decay Modes

144Ba

144Ba Decay Modes

145Ba

145Ba Decay Modes

146Ba

146Ba Decay Modes

147Ba

147Ba Decay Modes

148Ba

148Ba Decay Modes

149Ba

149Ba Decay Modes

150Ba

150Ba Decay Modes

151Ba

151Ba Decay Modes

152Ba

152Ba Decay Modes

153Ba

153Ba Decay Modes