42 · Mo
Molybdenum
Acid prepared by Scheele in 1778, metal isolated by Hjelm in 1781.
Identity
- Atomic number
- 42
- Symbol
- Mo
- Canonical name
- Molybdenum
- Category
- transition metal
- Group
- 6
- Period
- 5
- Block
- d
Properties
These quantities come from the Periodic Table JSON compilation. They have not yet been checked, one by one, against CIAAW atomic weights or NIST measurements. A value marked estimated is not a measurement.
- Atomic mass
- 95.951 u
- Electron configuration
- [Kr] 4d5 5s1
- Electrons per shell
- 2, 8, 18, 13, 1
- Standard state
- solid
- Density
- 10.28 g/cm³
- Melting point
- 2,896 K
- Boiling point
- 4,912 K
- Electronegativity
- 2.16 Pauling
- First ionization energy
- 684.3 kJ/mol
- Electron affinity
- 72.1 kJ/mol
History
Molybdic acid
Observation · confirmed · 1778
Scheele shows that molybdenite is not a lead or graphite ore and prepares the acid.
Metal isolated
Isolation · confirmed · 1781
Hjelm reduces the acid and obtains molybdenum.
Etymology
- Theme
- mineral
- Language
- grec
- Root
- molybdos
- Meaning
- lead
Scientists
See also
Sources
- IUPAC, Periodic Table of the Elements
- Bowserinator, Periodic Table JSON. Compilation secondaire d’où viennent les grandeurs physiques importées (masse, densité, températures, énergies). Elles ne sont pas revérifiées une à une auprès du NIST ou de la CIAAW.
- John Emsley, Nature’s Building Blocks: An A–Z Guide to the Elements