Technical data for Tellurium

Overview Name Tellurium Symbol Te Atomic Number 52 Atomic Weight 127.6 Density 6.24 g/cm3 Melting Point 449.51 °C Boiling Point 988 °C Thermal properties Phase Solid Melting Point 449.51 °C Boiling Point 988 °C Absolute Melting Point 722.66 K Absolute Boiling Point 1261 K Critical Pressure N/A Critical Temperature N/A Heat of Fusion 17.5 kJ/mol Heat of Vaporization 48 kJ/mol Specific Heat 201 J/(kg K)[note] Adiabatic Index N/A Neel Point N/A Thermal Conductivity 3 W/(m K) Thermal Expansion N/A Bulk physical properties Density 6.24 g/cm3 Density (Liquid) 5.7 g/cm3 Molar Volume 0.000020449 Brinell Hardness 180 MPa Mohs Hardness 2.25 Vickers Hardness N/A Bulk Modulus 64 GPa Shear Modulus 16 GPa Young Modulus 43 GPa Poisson Ratio N/A Refractive Index 1.000991 Speed of Sound 2610 m/s Thermal Conductivity 3 W/(m K) Thermal Expansion N/A Reactivity Valence 6 Electronegativity 2.1 ElectronAffinity 190.2 kJ/mol Ionization Energies 869.3, 1790, 2698, 3610, 5668, 6820, 13200 kJ/mol Health and Safety DOT Hazard Class 6.1 DOT Numbers 2811 RTECS Number RTECSWY2625000 NFPA Label

Classifications Alternate Names None Names of Allotropes None Block p Group 16 Period 5 Series Chalcogen Electron Configuration [Kr]5s24d105p4 Color Silver Discovery 1783 in Romania Gas phase N/A CAS Number CAS13494-80-9 CID Number CID6327182 RTECS Number RTECSWY2625000 Electrical properties Electrical Type Semiconductor Electrical Conductivity 10000 S/m Resistivity 0.0001 m Ω Superconducting Point N/A Magnetic properties Magnetic Type Diamagnetic Curie Point N/A Mass Magnetic Susceptibility -3.9×10-9 m3/Kg Molar Magnetic Susceptibility -4.98×10-10 m3/mol Volume Magnetic Susceptibility -0.0000243 Abundances % in Universe 9×10-7% % in Sun N/A % in Meteorites 0.00021% % in Earth's Crust 1×10-7% % in Oceans N/A % in Humans N/A Atomic dimensions and structure Atomic Radius 123 pm Covalent Radius 138 pm Van der Waals Radius 206 pm Crystal Structure Simple Trigonal Lattice Angles π/2, π/2, 2 π/3 Lattice Constants 445.72, 445.72, 592.9 pm Space Group Name P3121 Space Group Number 152 Nuclear Properties Half-Life Stable Lifetime Stable Decay Mode N/A Quantum Numbers 3P2 Neutron Cross Section 5.4 Neutron Mass Absorption 0.0013 Known Isotopes 105Te, 106Te, 107Te, 108Te, 109Te, 110Te, 111Te, 112Te, 113Te, 114Te, 115Te, 116Te, 117Te, 118Te, 119Te, 120Te, 121Te, 122Te, 123Te, 124Te, 125Te, 126Te, 127Te, 128Te, 129Te, 130Te, 131Te, 132Te, 133Te, 134Te, 135Te, 136Te, 137Te, 138Te, 139Te, 140Te, 141Te, 142Te Stable Isotopes 120Te, 122Te, 124Te, 125Te, 126Te Isotopic Abundances 120Te 0.09% 122Te 2.55% 123Te 0.89% 124Te 4.74% 125Te 7.07% 126Te 18.84% 128Te 31.74% 130Te 34.08%