Mendelevium (Md)

From Wikipedia, the free encyclopediaMendelevium is a synthetic element with chemical symbol Md (formerly Mv) and atomic number 101. A metallic radioactive transuranic element in the actinide series, it is the first element that currently cannot be produced in macroscopic quantities through neutron bombardment of lighter elements. It is the antepenultimate actinide and the ninth transuranic element.

Mendelevium in the periodic table

Atomic number101
Element categoryActinide

Physical properties

Phase at STPSolid
Density g/cm3
Atomic weight258 u
Melting point1100 K
826.85 °C
1520.33 °F
Boiling point K

Atomära egenskaper

Electronegativity (Pauling Scale)1.3
Electron affinity93.91 kJ/mol
Ionization energies
1635 kJ/mol

Electron configuration

Electron configuration1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d10 5f13 6s2 6p6 7s2
Electrons per shell2, 8, 18, 32, 31, 8, 2


Discovered byLawrence Berkeley National Laboratory