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86Rn

Element 86

Radon

Noble gases

Radon is a chemical element with symbol Rn and atomic number 86.

Key data

Atomic number
86
Atomic mass
222.000 u
Group / Period
18 / 6
Block
p-block
Phase at STP
Gas
Density
9.73 g/cm³
Melting point
-71.1 °C
Boiling point
-61.6 °C
Electron configuration
[Xe] 4f14 5d10 6s2 6p6

Common uses

  • Radon-gas testing
  • Cancer therapy (historical)
  • Radioactive

Discovery

Year: 1900

Discovered by: Friedrich Ernst Dorn

Frequently asked questions

What is the atomic number of Radon?

Radon has atomic number 86. Its symbol is Rn and its atomic mass is 222 u.

What category of element is Radon?

Radon is classified as noble gases. It sits in group 18, period 6 of the periodic table.

What is Radon used for?

Common uses of Radon include: Radon-gas testing, Cancer therapy (historical), Radioactive.

When was Radon discovered?

Radon was discovered in 1900 by Friedrich Ernst Dorn.

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