Technical data for Barium

Overview Name Barium Symbol Ba Atomic Number 56 Atomic Weight 137.327 Density 3.51 g/cc Melting Point 727.°C Boiling Point 1870.°C Thermal properties Phase Solid Melting Point 727.°C Boiling Point 1870.°C Absolute Melting Point 1.×103K Absolute Boiling Point 2143.K Critical Pressure N/A Critical Temperature N/A Heat of Fusion 8.KJ/mol Heat of Vaporization 140.KJ/mol Heat of Combustion N/A Specific Heat 205.J/(Kg K)[note] Adiabatic Index N/A Neel Point N/A Thermal Conductivity 18.W/(m K) Thermal Expansion 0.0000206K-1 Bulk physical properties Density 3.51 g/cc Density (Liquid) 3.338 g/cc Molar Volume 0.000039125 Brinell Hardness N/A Mohs Hardness 1.25MPa Vickers Hardness N/A Bulk Modulus 9.6GPa Shear Modulus 4.9GPa Young Modulus 13.GPa Poisson Ratio N/A Refractive Index N/A Speed of Sound 1620.m/s Thermal Conductivity 18.W/(m K) Thermal Expansion 0.0000206K-1 Reactivity Valence 2 Electronegativity 0.89 ElectronAffinity 13.95KJ/mol Ionization Energies 502.9, 965.2, 3.6×103 KJ/mol Health and Safety Autoignition Point N/A Flashpoint N/A Heat of Combustion N/A DOT Hazard Class 4.3 DOT Numbers 1400 EU Number EU231-149-1 NFPA Fire Rating 1 NFPA Hazards Water Reactive NFPA Health Rating 2 NFPA Reactivity Rating 2 RTECS Classes Other RTECS Number RTECSCQ8370000 NFPA Label

Classifications Alternate Names None Names of Allotropes None Block s Group 2 Period 6 Electron Configuration [Xe]6s2 Color Silver Discovery 1808 in United Kingdom Gas phase N/A CAS Number CAS7440-39-3 CID Number CID5355457 Gmelin Number Gmelin16266 NSC Number N/A RTECS Number RTECSCQ8370000 Electrical properties Electrical Type Conductor Electrical Conductivity 2.9×106S/m Resistivity 3.5×10-7m Ω Superconducting Point N/A Magnetic properties Magnetic Type Paramagnetic Curie Point N/A Mass Magnetic Susceptibility 1.13×10-8 Molar Magnetic Susceptibility 1.552×10-9 Volume Magnetic Susceptibility 0.00003966 Abundances % in Universe 1.×10-6% % in Sun 1.×10-6% % in Meteorites 0.00027% % in Earth's Crust 0.034% % in Oceans 3.×10-6% % in Humans 0.00003% Atomic dimensions and structure Atomic Radius 253.pm Covalent Radius 198.pm Van der Waals Radius N/A Crystal Structure Body Centered Cubic Lattice Angles π/2, π/2, π/2 Lattice Constants 502.8, 502.8, 502.8 pm Space Group Name Im_ 3m Space Group Number 229 Nuclear Properties Half-Life Stable Lifetime Stable Decay Mode N/A Quantum Numbers 1S0 Neutron Cross Section 1.3 Neutron Mass Absorption 0.00027 Known Isotopes 114Ba, 115Ba, 116Ba, 117Ba, 118Ba, 119Ba, 120Ba, 121Ba, 122Ba, 123Ba, 124Ba, 125Ba, 126Ba, 127Ba, 128Ba, 129Ba, 130Ba, 131Ba, 132Ba, 133Ba, 134Ba, 135Ba, 136Ba, 137Ba, 138Ba, 139Ba, 140Ba, 141Ba, 142Ba, 143Ba, 144Ba, 145Ba, 146Ba, 147Ba, 148Ba, 149Ba, 150Ba, 151Ba, 152Ba, 153Ba Stable Isotopes 130Ba, 132Ba, 134Ba, 135Ba, 136Ba, 137Ba, 138Ba Isotopic Abundances 130Ba 0.106% 132Ba 0.101% 134Ba 2.417% 135Ba 6.592% 136Ba 7.854% 137Ba 11.232% 138Ba 71.698%