95 Am 243

Americium

actinide

Properties

Atomic number
95
Atomic mass
243 u
Category
actinide
Group
f-block
Period
7
Block
f-block
State (room temp)
Solid
Outer-shell electrons
2
Electronegativity
1.13 (Pauling)
Density
12 g/cm³
Melting point
1175.85 °C
Boiling point
2606.85 °C

Electron configuration

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f⁷

Noble-gas shorthand: [Rn] 5f⁷ 7s²

Electrons per shell: 2, 8, 18, 32, 25, 8, 2, which is 2 in the outermost shell.

Related: electron configuration, the Bohr model, valence electrons.

Am
Bohr model; outer-shell electrons in blue

About Americium

Americium is a radioactive transuranic chemical element with symbol Am and atomic number 95. This member of the actinide series is located in the periodic table under the lanthanide element europium, and thus by analogy was named after the Americas. Americium was first produced in 1944 by the group of Glenn T.Seaborg from Berkeley, California, at the metallurgical laboratory of University of Chicago.

Americium: frequently asked questions

What is Americium?
Americium (Am) is the chemical element with atomic number 95. It is a metal: specifically an actinide.
What is the atomic number of Americium?
Americium's atomic number is 95, which means every Americium atom has 95 protons in its nucleus.
What is the electron configuration of Americium?
The electron configuration of Americium is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f7 (noble-gas shorthand: [Rn] 5f7 7s2). Its electrons are arranged in shells of 2, 8, 18, 32, 25, 8, 2, with 2 in the outermost shell.
Is Americium a metal or a nonmetal?
Americium is a metal: specifically an actinide.
What group and period is Americium in?
Americium sits in the f-block (the actinide row) of period 7 on the periodic table.
Is Americium a solid, liquid, or gas?
At room temperature, Americium is a solid.

Position in the periodic table

Open the interactive periodic table →

Data compiled from Wikipedia, PubChem, and IUPAC. Source.