1. 86
Radón – Radon
Mass: 222 u
1s2
2s2
2p6
3s2
3p6
4s2
3d10
4p6
5s2
4d10
5p6
6s2
4f14
5d10
6p6
Melting point: 202 K
Boiling point: 211 K
Density: 9.7 kg/m3
Discovery: F. Ernst Dorn (1900)
It is a radioactive, colorless, odorless and tasteless noble gas,
ocurring naturally as an indirect decay product of uranium and thorium.
It is also the only gas under normal conditions that only has isotopes,
and is considered a health hazard due to its radioactivity.