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88Ra

Element 88

Radium

Alkaline earth

Radium is a chemical element with symbol Ra and atomic number 88.

Key data

Atomic number
88
Atomic mass
226.000 u
Group / Period
2 / 7
Block
s-block
Phase at STP
Solid
Density
5.5 g/cm³
Melting point
959.9 °C
Boiling point
1736.8 °C
Electron configuration
[Rn] 7s2

Common uses

  • Glow-in-the-dark paints (historical)
  • Cancer therapy
  • Highly radioactive

Discovery

Year: 1898

Discovered by: Pierre Curie

Frequently asked questions

What is the atomic number of Radium?

Radium has atomic number 88. Its symbol is Ra and its atomic mass is 226 u.

What category of element is Radium?

Radium is classified as alkaline earth. It sits in group 2, period 7 of the periodic table.

What is Radium used for?

Common uses of Radium include: Glow-in-the-dark paints (historical), Cancer therapy, Highly radioactive.

When was Radium discovered?

Radium was discovered in 1898 by Pierre Curie.

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