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86Rn222.000
Noble Gasp-blockRadioactive

Radon

Element 86 on the periodic table, symbol Rn, group 18, period 6.

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.

Appearance: colorless gas, occasionally glows green or red in discharge tubes

Properties

Atomic Number
86
Atomic Mass
222.0000 u
Group
18
Period
6
Block
p-block
Category
Noble Gas
State at 25 °C
Gas
Melting Point
202 K · -71.1 °C
Boiling Point
211.5 K · -61.6 °C
Density
9.73 g/L
Atomic Radius
120 pm
Electronegativity
2.2
Oxidation States
0, +2
Abundance in Crust
4.00e-13 mg/kg
Discovered
1900
Discovered By
Friedrich Ernst Dorn

Electron Configuration

[Xe] 4f14 5d10 6s2 6p6

1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6

Ionisation Energies (kJ/mol)

  1. 1. 1,037

Elements near Radon

Elements in the same group share the number of outer electrons and behave in similar ways. Elements in the same period share a shell, so they change steadily from left to right.

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