Actinium

From Simple English Wikipedia, the free encyclopedia

Actinium is chemical element 89 on the periodic table. Its symbol is Ac. Actinium's mass is 227 g/mol.

Actinium is a silver radioactive metal. It is so radioactive that it glows in the dark. Even a small amount of actinium is dangerous to people.

Actinium was discovered in 1899 by André-Louis Debierne, a French chemist.