Technical data for Germanium

Overview Name Germanium Symbol Ge Atomic Number 32 Atomic Weight 72.63 Density 5.323 g/cm3 Melting Point 938.3 °C Boiling Point 2820 °C Thermal properties Phase Solid Melting Point 938.3 °C Boiling Point 2820 °C Absolute Melting Point 1211.4 K Absolute Boiling Point 3093 K Critical Pressure N/A Critical Temperature N/A Heat of Fusion 31.8 kJ/mol Heat of Vaporization 334 kJ/mol Specific Heat 321.4 J/(kg K)[note] Adiabatic Index N/A Neel Point N/A Thermal Conductivity 60 W/(m K) Thermal Expansion 6×10-6 K-1 Bulk physical properties Density 5.323 g/cm3 Density (Liquid) 5.6 g/cm3 Molar Volume 0.000013645 Brinell Hardness 7273.402498871 MPa[note] Mohs Hardness 6 Vickers Hardness 8012.03305 MPa[note] Bulk Modulus N/A Shear Modulus N/A Young Modulus N/A Poisson Ratio N/A Refractive Index N/A Speed of Sound 5400 m/s Thermal Conductivity 60 W/(m K) Thermal Expansion 6×10-6 K-1 Reactivity Valence 4 Electronegativity 2.01 ElectronAffinity 119 kJ/mol Ionization Energies 762, 1537.5, 3302.1, 4411, 9020 kJ/mol Health and Safety DOT Hazard Class 4.1 DOT Numbers 3089 RTECS Number RTECSLY5200000 NFPA Label

Classifications Alternate Names None Names of Allotropes None Block p Group 14 Period 4 Series Metalloid Electron Configuration [Ar]4s23d104p2 Color Gray Discovery 1886 in Germany Gas phase N/A CAS Number CAS7440-56-4 CID Number CID6326954 RTECS Number RTECSLY5200000 Electrical properties Electrical Type Semiconductor Electrical Conductivity 2000 S/m Resistivity 0.0005 m Ω Superconducting Point N/A Magnetic properties Magnetic Type Diamagnetic Curie Point N/A Mass Magnetic Susceptibility -1.5×10-9 m3/Kg Molar Magnetic Susceptibility -1.09×10-10 m3/mol Volume Magnetic Susceptibility -7.98×10-6 Abundances % in Universe 0.00002% % in Sun 0.00002% % in Meteorites 0.0021% % in Earth's Crust 0.00014% % in Oceans 6×10-9% % in Humans N/A Atomic dimensions and structure Atomic Radius 125 pm Covalent Radius 120 pm Van der Waals Radius N/A Crystal Structure Face-centered Cubic Lattice Angles π/2, π/2, π/2 Lattice Constants 565.75, 565.75, 565.75 pm Space Group Name Fm_ 3m Space Group Number 225 Nuclear Properties Half-Life Stable Lifetime Stable Decay Mode N/A Quantum Numbers 3P0 Neutron Cross Section 2.2 Neutron Mass Absorption 0.0011 Known Isotopes 58Ge, 59Ge, 60Ge, 61Ge, 62Ge, 63Ge, 64Ge, 65Ge, 66Ge, 67Ge, 68Ge, 69Ge, 70Ge, 71Ge, 72Ge, 73Ge, 74Ge, 75Ge, 76Ge, 77Ge, 78Ge, 79Ge, 80Ge, 81Ge, 82Ge, 83Ge, 84Ge, 85Ge, 86Ge, 87Ge, 88Ge, 89Ge Stable Isotopes 70Ge, 72Ge, 73Ge, 74Ge Isotopic Abundances 70Ge 20.84% 72Ge 27.54% 73Ge 7.73% 74Ge 36.28% 76Ge 7.61%