chemical element with the atomic number of 95

Americium is a chemical element. It is a radioactive metal. It has the chemical symbol Am. It has the atomic number 95. In chemistry it is placed in a group of metal elements named the actinides. Americium is a transuranic element (Transuranic means after uranium. All the elements used after uranium are man-made). It is a radioactive element that does not exist in nature. Americium has to be made. It has a silver color. Americium is made by bombarding a plutonium target with neutrons.

It was the fourth transuranic element to be discovered. It was named for America, like Francium was named for France.

The longest half life of any type of americium is 7370 years.[1]


Americium is used in most smoke detectors. The level of radioactivity is not enough to cause cancer, so it is safe to live in a place where smoke detectors with americium are used.


  1. "Americium Video - The Periodic Table of Videos - University of Nottingham". Retrieved 2022-04-19.