Name Americium
Symbol Am
Atomic Number 95
Atomic Mass 243.0 atomic mass units
Number of Protons 95
Number of Neutrons 148
Number of Electrons 95
Melting Point 994.2 C
Boiling Point 2607.0 C
Density 13.6 grams per cubic centimeter
Normal Phase Synthetic
Family Rare Earth Metals
Period 7
Cost $160 per milligram



Origin of Name After America
Date and Place of Discovery In 1944 in America
Discovered by Glenn T. Seaborg, Ralph James, L. Morgan and Albert Ghiorso
Common Compounds
Interesting facts
  • It was discovered as a by-product of the Manhattan Project when testing the atomic bomb.
  • It is created by bombarding plutonium with neutrons.
  • It is very expensive to produce in usable quantities.
Common Uses
  • Smoke detectors
  • Ionization of radiation
  • Radiography
  • Flat glass
  • Gauge for glass thickness


Photo Courtesy of
Cary Academy
Chemical Elements
Jefferson Lab
Mrs. Purdy's Web Page
Web Elements

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