Radium has two valence electrons. It is number 88 on the Periodic Table, meaning it has 88 protons and electrons. Therefore its electron configuration is 2, 8, 18, 32, 18, 8, 2, leaving 2 unpaired valence electrons in the outer shell.
Radium is an alkali earth metal that is very radioactive. Discovered by the French scientist couple Marie and Pierre Curie, radium's dangerous radioactivity eventually led to Marie's premature death. As a result, radium is rarely produced and barely worked with in chemical laboratories. Its instability renders it too dangerous for consumer use, even though it was originally used in luminescent paints and cancer treatments.