Radon

Noble gas · atomic number 86

86222RnRadonGasNoble gas

Radon is a chemical element with symbol Rn and atomic number 86. It is a radioactive, colorless, odorless, tasteless noble gas, occurring naturally as a decay product of radium. Its most stable isotope, 222Rn, has a half-life of 3.8 days.

Properties of Radon

Element category	Noble gas
Atomic number	86
Atomic mass	222 u
Phase at STP	Gas
Group	18
Period	6
Block	p
Electron configuration	[Xe] 4f14 5d10 6s2 6p6
Electrons per shell	2, 8, 18, 32, 18, 8
Electronegativity (Pauling)	2.2
Melting point	202 K (-71 °C)
Boiling point	211.5 K (-62 °C)
Density	9.73 g/L
Discovered by	Friedrich Ernst Dorn

← Astatine · Periodic table · Francium → Fr

About the noble gas group

Full outer electron shells make these gases almost inert: they barely react, glow in discharge lamps and are used to create unreactive atmospheres.

Data: Periodic-Table-JSON (CC BY-SA 3.0) · stored statically on our server. https://en.wikipedia.org/wiki/Radon

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🧪 Reactive nonmetal

11 elements: Elements that readily gain or share electrons — the building blocks of water, air, living tissue and most organic chemistry.

🧪 Noble gas

6 elements: Full outer electron shells make these gases almost inert: they barely react, glow in discharge lamps and are used to create unreactive atmospheres.

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6 elements: Soft, wildly reactive metals of group 1 — they fizz in water and never occur pure in nature. Lithium, sodium, potassium and friends.

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