Element 86
Radon
Noble gases
Radon (Rn) is in the p-block of the periodic table — group 18, period 6.
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
Periodic table block
Radon is in the p-block (group 18, period 6). Elements land in the p-block when their highest-energy electrons fill a p subshell — this region holds most nonmetals, the metalloids, and the metals on the right of the table.
New to this? Periodic table blocks explained: s, p, d, and f
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 block of the periodic table is Radon in?
Radon is in the p-block (group 18, period 6). Its highest-energy electrons occupy the p subshell — you can see this in its electron configuration, [Xe] 4f14 5d10 6s2 6p6.
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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