Americium: the essentials

The lustre of freshly prepared americium metal is whiter and more silvery than plutonium or neptunium prepared in the same manner. Americium is a component of the smoke detector above.

Americium appears to be more malleable than uranium or neptunium and americium tarnishes slowly in dry air at room temperature. Americium is a radioactive rare earth metal which must be handled with care to avoid contact, since it is a heavy α and γ emitter. It is named after America. The α activity of 241Am is about three times that of radium. Americium is available to qualified users in the UK and in the USA.

Table: basic information about and classifications of americium.

Americium: historical information

Americium was discovered by Glenn Seaborg, Ralph James., L. Morgan, Albert Ghiorso at 1944 in USA. Origin of name: from the English word "America".

Americium was was identified by Seaborg and others in 1944 as the result of successive neutron capture reactions by plutonium isotopes in a nuclear reactor.

Americium: physical properties

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Americium: orbital properties

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Isolation: coming soon!

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americium atomic number