85 At 210
Astatine
metalloid
Properties
- Atomic number
- 85
- Atomic mass
- 210 u
- Category
- metalloid
- Group
- 17
- Period
- 6
- Block
- p-block
- State (room temp)
- Solid
- Outer-shell electrons
- 7
- Electronegativity
- 2.2 (Pauling)
- Density
- 6.35 g/cm³
- Melting point
- 301.85 °C
- Boiling point
- 336.85 °C
Electron configuration
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁵
Noble-gas shorthand: [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁵
Electrons per shell: 2, 8, 18, 32, 18, 7, which is 7 in the outermost shell.
Related: electron configuration, the Bohr model, valence electrons.
About Astatine
Astatine is a very rare radioactive chemical element with the chemical symbol At and atomic number 85. It occurs on Earth as the decay product of various heavier elements. All its isotopes are short-lived; the most stable is astatine-210, with a half-life of 8.1 hours.
- Discovered by Dale R. Corson
- Appearance: unknown, probably metallic
Astatine: frequently asked questions
- What is Astatine?
- Astatine (At) is the chemical element with atomic number 85. It is a metalloid, with properties between metals and nonmetals.
- What is the atomic number of Astatine?
- Astatine's atomic number is 85, which means every Astatine atom has 85 protons in its nucleus.
- What is the electron configuration of Astatine?
- The electron configuration of Astatine is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p5 (noble-gas shorthand: [Xe] 4f14 5d10 6s2 6p5). Its electrons are arranged in shells of 2, 8, 18, 32, 18, 7, with 7 in the outermost shell.
- Is Astatine a metal or a nonmetal?
- Astatine is a metalloid, with properties between metals and nonmetals.
- What group and period is Astatine in?
- Astatine is in group 17 and period 6 of the periodic table.
- Is Astatine a solid, liquid, or gas?
- At room temperature, Astatine is a solid.
Position in the periodic table
Data compiled from Wikipedia, PubChem, and IUPAC. Source.