100 Fm 257
Fermium
actinide
Properties
- Atomic number
- 100
- Atomic mass
- 257 u
- Category
- actinide
- Group
- f-block
- Period
- 7
- Block
- f-block
- State (room temp)
- Solid
- Outer-shell electrons
- 2
- Electronegativity
- 1.3 (Pauling)
- Density
- -
- Melting point
- 1526.85 °C
- Boiling point
- -
Electron configuration
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f¹²
Noble-gas shorthand: [Rn] 5f¹² 7s²
Electrons per shell: 2, 8, 18, 32, 30, 8, 2, which is 2 in the outermost shell.
Related: electron configuration, the Bohr model, valence electrons.
About Fermium
Fermium is a synthetic element with symbol Fm and atomic number 100. It is a member of the actinide series. It is the heaviest element that can be formed by neutron bombardment of lighter elements, and hence the last element that can be prepared in macroscopic quantities, although pure fermium metal has not yet been prepared.
- Discovered by Lawrence Berkeley National Laboratory
Fermium: frequently asked questions
- What is Fermium?
- Fermium (Fm) is the chemical element with atomic number 100. It is a metal: specifically an actinide.
- What is the atomic number of Fermium?
- Fermium's atomic number is 100, which means every Fermium atom has 100 protons in its nucleus.
- What is the electron configuration of Fermium?
- The electron configuration of Fermium is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f12 (noble-gas shorthand: [Rn] 5f12 7s2). Its electrons are arranged in shells of 2, 8, 18, 32, 30, 8, 2, with 2 in the outermost shell.
- Is Fermium a metal or a nonmetal?
- Fermium is a metal: specifically an actinide.
- What group and period is Fermium in?
- Fermium sits in the f-block (the actinide row) of period 7 on the periodic table.
- Is Fermium a solid, liquid, or gas?
- At room temperature, Fermium is a solid.
Position in the periodic table
Data compiled from Wikipedia, PubChem, and IUPAC. Source.