Element 96
Curium (Cm)
Curium (Cm) is element 96 of the periodic table, a actinide in period 7 (f-block) with an atomic mass of 247 and is a solid at standard conditions.
At a glance
- Atomic number
- 96
- Symbol
- Cm
- Atomic mass
- 247 u
- Category
- Actinides
- Period
- 7
- Block
- f-block
- Phase at STP
- solid
Electron structure
- Electron configuration
- 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d10 6s2 6p6 5f7 6d1 7s2
- Shorthand configuration
- [Rn] 5f7 6d1 7s2
- Electrons per shell
- 2, 8, 18, 32, 25, 9, 2
- Oxidation states
- +3, +4, +5, +6
Physical properties
- Melting point
- 1613 K
- Boiling point
- 3383 K
- Density
- 13.51 g/cm3
- Phase
- solid
Atomic properties
- Electronegativity (Pauling)
- 1.3
- Atomic radius
- 174 pm
- Covalent radius
- 169 pm
- First ionization energy
- 581 kJ/mol
- Electron affinity
- 28 kJ/mol
Notable isotopes
| Isotope | Mass | Abundance | Stability |
|---|---|---|---|
| Cm-247 | 247.07035 | — | Half-life 15.6 million years |
Common uses
- Space missions power
- Pacemakers
- Scientific research
Discovery
- Year
- 1944
- Discovered by
- Glenn T. Seaborg, Ralph A. James, Albert Ghiorso
- Country
- USA