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95Am

Element 95

Americium

Actinides

Americium is a radioactive transuranic chemical element with symbol Am and atomic number 95.

Key data

Atomic number
95
Atomic mass
243.000 u
Group / Period
3 / 7
Block
f-block
Phase at STP
Solid
Density
12 g/cm³
Melting point
1175.8 °C
Boiling point
2606.8 °C
Electron configuration
[Rn] 5f7 7s2

Common uses

  • Smoke detectors
  • Industrial gauging
  • Research only

Discovery

Year: 1944

Discovered by: Glenn T. Seaborg

Frequently asked questions

What is the atomic number of Americium?

Americium has atomic number 95. Its symbol is Am and its atomic mass is 243 u.

What category of element is Americium?

Americium is classified as actinides. It sits in group 3, period 7 of the periodic table.

What is Americium used for?

Common uses of Americium include: Smoke detectors, Industrial gauging, Research only.

When was Americium discovered?

Americium was discovered in 1944 by Glenn T. Seaborg.

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