Technical data for Carbon

Overview Name Carbon Symbol C Atomic Number 6 Atomic Weight 12.0107 Density 2.26 g/cm3[note] Melting Point 3550 °C[note] Boiling Point 4027 °C[note] Thermal properties Phase Solid Melting Point 3550 °C[note] Boiling Point 4027 °C[note] Absolute Melting Point 3823 K[note] Absolute Boiling Point 4300 K[note] Critical Pressure N/A Critical Temperature N/A Heat of Fusion 105 kJ/mol Heat of Vaporization 715 kJ/mol Heat of Combustion {"N/A", -393., "N/A", "N/A"} J/(kg K) Specific Heat 710 J/(kg K)[note] Adiabatic Index N/A Neel Point N/A Thermal Conductivity 140 W/(m K) Thermal Expansion 7.1×10-6 K-1[note] Bulk physical properties Density 2.26 g/cm3[note] Density (Liquid) N/A Molar Volume 5.3145×10-6 Brinell Hardness N/A Mohs Hardness 0.5 MPa[note] Vickers Hardness N/A Bulk Modulus 33 GPa Shear Modulus N/A Young Modulus N/A Poisson Ratio N/A Refractive Index 2.417[note] Speed of Sound 18350 m/s Thermal Conductivity 140 W/(m K) Thermal Expansion 7.1×10-6 K-1[note] Reactivity Valence 4 Electronegativity 2.55 ElectronAffinity 153.9 kJ/mol Ionization Energies 1086.5, 2352.6, 4620.5, 6222.7, 37831, 47277 kJ/mol Health and Safety Autoignition Point N/A Flashpoint N/A[note] Heat of Combustion {"N/A", -393., "N/A", "N/A"} J/(kg K) DOT Hazard Class {N/A, 4.2, N/A, N/A} DOT Numbers "N/A", {1361}, "N/A", "N/A" EU Number {N/A, N/A, N/A, N/A} NFPA Fire Rating {N/A, 1, N/A, 1} NFPA Hazards N/ A, N/ A, N/ A, N/ A NFPA Health Rating {N/A, 0, N/A, 1} NFPA Reactivity Rating {N/A, 0, N/A, 0} RTECS Number {RTECSHL4158550, RTECSFF5250100, RTECSMD9659600, N/A} NFPA Label [note]

Classifications Alternate Names None Names of Allotropes Graphite, Diamond, AmorphousCarbon, Lonsdaleite, Fullerene, CarbonNanotube Block p Group 14 Period 2 Electron Configuration [He]2s22p2 Color Black Discovery N/A[note] Gas phase N/A CAS Number CAS7440-44-0 CID Number {CID5462310, CID5462310, CID5462310, CID123591} Gmelin Number {N/A, N/A, N/A, N/A} NSC Number {N/A, N/A, N/A, N/A} RTECS Number {RTECSHL4158550, RTECSFF5250100, RTECSMD9659600, N/A} Electrical properties Electrical Type Conductor[note] Electrical Conductivity 1×105 S/m[note] Resistivity 1×10-5 m Ω[note] Superconducting Point N/A Magnetic properties Magnetic Type Diamagnetic Curie Point N/A Mass Magnetic Susceptibility -6.2×10-9 Molar Magnetic Susceptibility -7.45×10-11 Volume Magnetic Susceptibility -0.000014 Abundances % in Universe 0.5% % in Sun 0.3% % in Meteorites 1.5% % in Earth's Crust 0.18% % in Oceans 0.0028% % in Humans 23% Atomic dimensions and structure Atomic Radius 67 pm Covalent Radius 77 pm Van der Waals Radius 170 pm Crystal Structure Simple Hexagonal Lattice Angles π/2, π/2, 2 π/3 Lattice Constants 246.4, 246.4, 671.1 pm Space Group Name P63/mmc Space Group Number 194 Nuclear Properties Half-Life Stable Lifetime Stable Decay Mode N/A Quantum Numbers 3P0 Neutron Cross Section 0.0035 Neutron Mass Absorption 0.000015 Known Isotopes 8C, 9C, 10C, 11C, 12C, 13C, 14C, 15C, 16C, 17C, 18C, 19C, 20C, 21C, 22C Stable Isotopes 12C, 13C Isotopic Abundances 12C 98.93% 13C 1.07%