Radium is Discovered

After 2 years of research, Marie and Pierre discovered the new element which they named radium. They found this by starting with barium and each time they managed to take a small amount of barium away, they were left with a substance that gave off 300 times stronger waves then uranium. This was also the first time that the word radioactivity was used. Marie figures that the amount of radioactivity depends on the interior of an atom, rather then the arrangement of atoms in molecule.