101Unknown
Md 258 Atomic mass · uActinides
Mendelevium
Mendelevium 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.
Discovery 1955 (Lawrence Berkeley National Laboratory)
K2L8M18N32O31P8Q2
Physical properties
Values for the element in its standard state.
- Density
- Not available
- Melting point
- 1,100K
- Boiling point
- Not available
- Atomic radius
- Not available
- Bonding type
- Not recorded
- Molar heat
- Not available
Inside the atom
Electron arrangement and the energy behind its behavior.
Full electron configuration
1s, 2 electrons; 2s, 2 electrons; 2p, 6 electrons; 3s, 2 electrons; 3p, 6 electrons; 3d, 10 electrons; 4s, 2 electrons; 4p, 6 electrons; 4d, 10 electrons; 5s, 2 electrons; 5p, 6 electrons; 4f, 14 electrons; 5d, 10 electrons; 6s, 2 electrons; 6p, 6 electrons; 5f, 13 electrons; 7s, 2 electrons;
[Rn] represents 86 core electrons. The full view shows them explicitly.
101 electrons Orbital order preserved from source
- Electronegativity
- 1.3Pauling scale
- First ionization energy
- 635kJ/mol
- Electron affinity
- Not available
- Van der Waals radius
- Not available
Md MendeleviumAtomic number 101
635kJ/mol
Atomic numberGaps indicate unavailable data
About mendelevium
- Appearance
- Not recorded
- Discovery
- 1955 (Lawrence Berkeley National Laboratory)
- Data source
- Read the reference
A missing value means it is unavailable in this reference dataset. Values can vary with measurement method and conditions.