Tuesday, December 18, 2012

Radium is a highly radiactive metallic element which produces radon and alpha rays when it disintegrates, with the latter being regarded a positively charged particles of helium. The disintegration of radium is understood to be a process by which an atom radium breaks down into an atom of helium, the material of alpha rays, and into an atom of radon, the material of radium emanation. Symbol Ra; atomic weight, 226; valence, 2.