88 Ra
Alkaline earth metal
Radium
Glows in the dark.
Properties of Radium
- Atomic number (Z)
- 88
- Symbol
- Ra
- Atomic mass
- 226 g/mol
- Category
- Alkaline earth metal
- Group
- 2
- Period
- 7
- Electron configuration
- [Rn] 7s²
- Electronegativity (Pauling)
- 0.9
- Atomic radius
- 215 pm
- First ionization energy
- 509 kJ/mol
- Melting point
- 973 K (699.9 °C)
- Boiling point
- 2010 K (1736.8 °C)
- Density
- 5.5 g/cm³
- Phase at 25 °C
- Solid
- Discovered
- Discovered in 1898
Frequently asked questions
What is Radium?
Radium (Ra) is an alkaline earth metal, element number 88 on the periodic table. Glows in the dark.
What is the atomic number and atomic mass of Radium?
Radium has atomic number 88 and an atomic mass of about 226 g/mol.
What is the electron configuration of Radium?
The electron configuration of Radium is [Rn] 7s².
Where is Radium on the periodic table?
Radium sits in group 2, period 7, and is classified as a alkaline earth metal.