Atomic number: 88
Category: Alkali earth metal
Density at 25°C: solid: density: 5.5 g·cm−3
Radium occurs in nature as part of uraninite ores but only in very trace quantities. It is most well know as being discovered by Marie Skłodowska-Curie and Pierre Curie in 1898. It was historically important in the scientific study of radioactivity and developing technologies for using radiation.
Use, natural applications or common combinations:
- historically for fluorescent paints
- historically used to discover the structure of the atom by Rutherford.
- Standard atomic weight: (226)
- Melting point: 700 °C
- Boiling point: 1737 °C
- Radioactivity: all radioactive
- 223Ra, 224Ra, 226Ra and 228Ra are all generated naturally in the decay of either uranium or thorium. 226Ra is the most stable with half life of 1601 years via alpha decay.