Radium

Atomic symbol: Ra
Atomic number: 88
Atomic mass: 226

Appearance: Silvery white metallic solid at 25°C

Group: 2
Period: 7
Series: Alkaline earth metals
Block: s
Electron configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s² 6p⁶ 7s²

Highly radioactive and carcinogenic, radium decays into radon gas, which originally led to radon’s discovery.

Radium’s compounds glow in the dark because it is extremely radioactive.

Fun Fact! Alongside polonium, radium was also discovered by scientist Marie Curie.