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95Am243 u

Americium

actinide
Atomic Number
95
Atomic Mass
243 u
Period
7
Group
3

Quick Facts

PropertyValue
SymbolAm
Atomic Number95
Atomic Mass[243] u
CategoryActinide
Period7
Group3
Blockf
Electron Configuration[Rn] 5f⁷ 7s²

History and Discovery

Discovered by: Glenn Seaborg and colleagues Year of Discovery: 1944 Location: Chicago, USA (Manhattan Project)

Etymology

Named after the Americas.

Applications and Uses

  • Smoke detectors (Am-241)—in most homes
  • Industrial gauges
  • Neutron sources

Interesting Facts

  1. Found in nearly every household smoke detector
  2. Named after America, paralleling europium (named after Europe)
  3. Produces mainly alpha radiation
  4. An average smoke detector contains about 1 microgram
  5. Discovered during the Manhattan Project but kept secret