- radium (Ra) by Dustin Matthews
Etymology: L, radius, ray. A radioactive metallic element of the alkaline earth group. Its atomic...
- radium by Elias Olson
radioactive metallic chemical element; symbol Ra; at. No. 88; at. Wt. 226.0254; m.p. 700°C;...
- radium by Raymond Richardson
A chemical element, atomic number 88, atomic weight, 226, symbol Ra. See Table 6. Radium is highly...
- Polonium by Webster's
(n.) A supposed new element, a radioactive substance discovered by M. and MMe. Curie in...
- pitchblende by Gerardo Spencer
Amorphous, dense, black, pitchy form of the crystalline uranium oxide mineral uraninite; it is one...