Radon is a chemical element with symbol Rn and atomic number 86. It is a radioactive, colorless, odorless, tasteless noble gas, occurring naturally as an indirect decay product of uranium or thorium.Symbol: Rn
Electron configuration: Xe 4f14 5d10 6s2 6p6
Atomic number: 86
Discovered: 1898
Boiling point: -61.85 °C
Atomic mass: 222 u