Americium

Actinide · atomic number 95

95243AmAmericiumSolidActinide

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.

Properties of Americium

Element category	Actinide
Atomic number	95
Atomic mass	243 u
Phase at STP	Solid
Group	3
Period	7
Block	f
Electron configuration	[Rn] 5f7 7s2
Electrons per shell	2, 8, 18, 32, 25, 8, 2
Electronegativity (Pauling)	1.13
Melting point	1449 K (1176 °C)
Boiling point	2880 K (2607 °C)
Density	12 g/cm3
Discovered by	Glenn T. Seaborg

← Plutonium · Periodic table · Curium → Cm

About the actinide group

Mostly radioactive, heavy metals — several made only in reactors — whose fission powers nuclear energy and weapons.

Data: Periodic-Table-JSON (CC BY-SA 3.0) · stored statically on our server. https://en.wikipedia.org/wiki/Americium

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