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42Mo95.951
Molybdenum
Transition MetalMolybdenum is a chemical element with symbol Mo and atomic number 42. The name is from Neo-Latin molybdaenum, from Ancient Greek Μόλυβδος molybdos, meaning lead, since its ores were confused with lead ores. Molybdenum minerals have been known throughout history, but the element was discovered (in the sense of differentiating it as a new entity from the mineral salts of other metals) in 1778 by Carl Wilhelm Scheele.
Phase: SolidAppearance: gray metallic
2, 8, 18, 13, 1
Physical Properties
Atomic Mass95.951 u
Density10.28 g/cm³
Melting Point2896 K
Boiling Point4912 K
Molar Heat24.06 J/(mol·K)
Period5
PhaseSolid
Chemical Properties
Electron Configuration1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 4d5
Semantic Config[Kr] 4d5 5s1
Shells2, 8, 18, 13, 1
Electron Affinity72.1 kJ/mol
Electronegativity2.16
Ionization Energies
IE1: 684.3 kJ/molIE2: 1560 kJ/molIE3: 2618 kJ/molIE4: 4480 kJ/molIE5: 5257 kJ/molIE6: 6640.8 kJ/molIE7: 12125 kJ/molIE8: 13860 kJ/molIE9: 15835 kJ/molIE10: 17980 kJ/molIE11: 20190 kJ/molIE12: 22219 kJ/molIE13: 26930 kJ/molIE14: 29196 kJ/molIE15: 52490 kJ/molIE16: 55000 kJ/molIE17: 61400 kJ/molIE18: 67700 kJ/molIE19: 74000 kJ/molIE20: 80400 kJ/molIE21: 87000 kJ/molIE22: 93400 kJ/molIE23: 98420 kJ/molIE24: 104400 kJ/molIE25: 121900 kJ/molIE26: 127700 kJ/molIE27: 133800 kJ/molIE28: 139800 kJ/molIE29: 148100 kJ/molIE30: 154500 kJ/mol
Discovery
Discovered byCarl Wilhelm Scheele