99 Es 252
Einsteinium
actinide
Properties
- Atomic number
- 99
- Atomic mass
- 252 u
- Category
- actinide
- Group
- f-block
- Period
- 7
- Block
- f-block
- State (room temp)
- Solid
- Outer-shell electrons
- 2
- Electronegativity
- 1.3 (Pauling)
- Density
- 8.84 g/cm³
- Melting point
- 859.85 °C
- Boiling point
- 995.85 °C
Electron configuration
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f¹¹
Noble-gas shorthand: [Rn] 5f¹¹ 7s²
Electrons per shell: 2, 8, 18, 32, 29, 8, 2, which is 2 in the outermost shell.
Related: electron configuration, the Bohr model, valence electrons.
About Einsteinium
Einsteinium is a synthetic element with symbol Es and atomic number 99. It is the seventh transuranic element, and an actinide. Einsteinium was discovered as a component of the debris of the first hydrogen bomb explosion in 1952, and named after Albert Einstein.
- Discovered by Lawrence Berkeley National Laboratory
- Appearance: silver-colored
Einsteinium: frequently asked questions
- What is Einsteinium?
- Einsteinium (Es) is the chemical element with atomic number 99. It is a metal: specifically an actinide.
- What is the atomic number of Einsteinium?
- Einsteinium's atomic number is 99, which means every Einsteinium atom has 99 protons in its nucleus.
- What is the electron configuration of Einsteinium?
- The electron configuration of Einsteinium is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f11 (noble-gas shorthand: [Rn] 5f11 7s2). Its electrons are arranged in shells of 2, 8, 18, 32, 29, 8, 2, with 2 in the outermost shell.
- Is Einsteinium a metal or a nonmetal?
- Einsteinium is a metal: specifically an actinide.
- What group and period is Einsteinium in?
- Einsteinium sits in the f-block (the actinide row) of period 7 on the periodic table.
- Is Einsteinium a solid, liquid, or gas?
- At room temperature, Einsteinium is a solid.
Position in the periodic table
Data compiled from Wikipedia, PubChem, and IUPAC. Source.