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- |
Atomic Radius | 215 pm
|
---|---|
Molar Volume | 39 cm³/mol
|
Covalent Radius | 196 pm
|
Metallic Radius | 198 pm
|
Ionic Radius | 135 pm
|
Crystal Radius | 149 pm
|
Van der Waals Radius | 268 pm
|
Density | 3.62 g/cm³
|
Energy | |
Proton Affinity | |
Electron Affinity | 0.14462 eV/particle
|
Ionization Energy | 5.211664 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 | 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 | |
Color | Silver
|
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 | |
Crystal Structure | Body Centered Cubic (BCC) |
Lattice Constant | 5.02 Å
|
Lattice Angles | π/2, π/2, π/2 |
Mechanical Properties | |
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 | |
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 | |
Gas Basicity | |
Dipole Polarizability | |
C6 Dispersion Coefficient | |
Allotropes | |
Neutron Cross Section | 1.3
|
Neutron Mass Absorption | 0.00027
|
Quantum Numbers | 1S0 |
Space Group | 229 (Im_3m) |
Stable Isotopes | 7 |
---|---|
Unstable Isotopes | 35 |
Radioactive Isotopes | 35 |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 113 |
G-Factor | |
Half Life | |
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | |
Parity | + |
Decay Mode | Intensity |
---|---|
p (proton emission) | % |
α (α emission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 114 |
G-Factor | 0
|
Half Life | 460 ± 125 ms
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1995 |
Parity | + |
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% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 115 |
G-Factor | |
Half Life | 450 ± 50 ms
|
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | 1997 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
β+ p (β+-delayed proton emission) | 15% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 116 |
G-Factor | 0
|
Half Life | 1.3 ± 0.2 s
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1997 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
β+ p (β+-delayed proton emission) | 3% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 117 |
G-Factor | |
Half Life | 1.75 ± 0.07 s
|
Spin | 3/2 |
Quadrupole Moment | |
Discovery Year | 1977 |
Parity | + |
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% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 118 |
G-Factor | 0
|
Half Life | 5.2 ± 0.2 s
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1997 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 119 |
G-Factor | |
Half Life | 5.4 ± 0.3 s
|
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | 1974 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
β+ p (β+-delayed proton emission) | 25% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 120 |
G-Factor | 0
|
Half Life | 24 ± 2 s
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1974 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
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 | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
β+ p (β+-delayed proton emission) | 0.02% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 122 |
G-Factor | 0
|
Half Life | 1.95 ± 0.15 m
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1974 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
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 | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 124 |
G-Factor | 0
|
Half Life | 11 ± 0.5 m
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1967 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
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 | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 126 |
G-Factor | 0
|
Half Life | 100 ± 2 m
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1954 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
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 | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 128 |
G-Factor | 0
|
Half Life | 2.43 ± 0.05 d
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1950 |
Parity | + |
Decay Mode | Intensity |
---|---|
ϵ (electron capture) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 129 |
G-Factor | |
Half Life | 2.23 ± 0.11 h
|
Spin | 1/2 |
Quadrupole Moment | 0
|
Discovery Year | 1950 |
Parity | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
Abundance | 0.11 ± 0.01
|
---|---|
Relative Atomic Mass | |
Mass Number | 130 |
G-Factor | 0
|
Half Life | |
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1936 |
Parity | + |
Decay Mode | Intensity |
---|---|
2β+ (double β+ decay) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
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 | + |
Decay Mode | Intensity |
---|---|
β+ (β+ decay; β+ = ϵ + e+) | 100% |
Abundance | 0.1 ± 0.01
|
---|---|
Relative Atomic Mass | |
Mass Number | 132 |
G-Factor | 0
|
Half Life | |
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1936 |
Parity | + |
Decay Mode | Intensity |
---|---|
2β+ (double β+ decay) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
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 | + |
Decay Mode | Intensity |
---|---|
ϵ (electron capture) | 100% |
Abundance | 2.42 ± 0.15
|
---|---|
Relative Atomic Mass | |
Mass Number | 134 |
G-Factor | 0
|
Half Life | |
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1936 |
Parity | + |
Abundance | 6.59 ± 0.1
|
---|---|
Relative Atomic Mass | |
Mass Number | 135 |
G-Factor | 0.55873333333333 ± 0.00013333333333333
|
Half Life | |
Spin | 3/2 |
Quadrupole Moment | 0.153 ± 0.002
|
Discovery Year | 1932 |
Parity | + |
Abundance | 7.85 ± 0.24
|
---|---|
Relative Atomic Mass | |
Mass Number | 136 |
G-Factor | 0
|
Half Life | |
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1932 |
Parity | + |
Abundance | 11.23 ± 0.23
|
---|---|
Relative Atomic Mass | |
Mass Number | 137 |
G-Factor | 0.625 ± 0.00013333333333333
|
Half Life | |
Spin | 3/2 |
Quadrupole Moment | 0.236 ± 0.003
|
Discovery Year | 1932 |
Parity | + |
Abundance | 71.7 ± 0.29
|
---|---|
Relative Atomic Mass | |
Mass Number | 138 |
G-Factor | 0
|
Half Life | |
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1925 |
Parity | + |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
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 | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 140 |
G-Factor | 0
|
Half Life | 12.7534 ± 0.0021 d
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1939 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
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 | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 142 |
G-Factor | 0
|
Half Life | 10.6 ± 0.2 m
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1959 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
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 | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 144 |
G-Factor | 0
|
Half Life | 11.73 ± 0.08 s
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1967 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
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 | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 146 |
G-Factor | 0
|
Half Life | 2.15 ± 0.04 s
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1970 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 147 |
G-Factor | |
Half Life | 893 ± 1 ms
|
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | 1978 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | 0.07% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 148 |
G-Factor | 0
|
Half Life | 620 ± 5 ms
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1979 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | 0.4% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 149 |
G-Factor | |
Half Life | 349 ± 4 ms
|
Spin | 3/2 |
Quadrupole Moment | |
Discovery Year | 1993 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | 3.9% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 150 |
G-Factor | 0
|
Half Life | 258 ± 5 ms
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 1994 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | 1% |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 151 |
G-Factor | |
Half Life | 167 ± 5 ms
|
Spin | 3/2 |
Quadrupole Moment | |
Discovery Year | 1994 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 152 |
G-Factor | 0
|
Half Life | 139 ± 8 ms
|
Spin | 0 |
Quadrupole Moment | 0
|
Discovery Year | 2010 |
Parity | + |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | % |
Abundance | Radioactive ☢️ |
---|---|
Relative Atomic Mass | |
Mass Number | 153 |
G-Factor | |
Half Life | 113 ± 39 ms
|
Spin | 5/2 |
Quadrupole Moment | |
Discovery Year | 2016 |
Parity | - |
Decay Mode | Intensity |
---|---|
β− (β− decay) | 100% |
β− n (β−-delayed neutron emission) | % |
2n (2-neutron emission) | % |
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) |
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 %
|
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 |