Facts about Americium

Toward this goal, the solvent extraction chemistry of americium may play an important role.

Americium (chemical symbol Am, atomic number 95) is a radioactive, synthetic metallic element, classified as an actinide.

Many radioisotopes of americium have been characterized, with the most stable being 243Am with a half-life of 7370 years, and 241Am with a half-life of 432.7 years.

Americium is an inner transition metal of the actinide series, located in period seven of the periodic table, between plutonium and curium.

Americium is also fissile; the critical mass for an unreflected sphere of 241Am is approximately 60 kilograms.

Americium has found its way into the household, where one type of smoke detector contains a tiny amount (about 0.2 microgram) of 241Am as a source of ionizing radiation.

The discovery of americium and curium was first announced informally on a children's quiz show in 1945.

The isotopes of americium range in atomic weight from 231.046 amu (231Am) to 249.078 amu (249Am).