Radon
Definition and meaning of Radon in chemistry.
Radon is a colorless, odorless, and highly radioactive noble gas with the chemical symbol Rn and atomic number 86. It is the heaviest naturally occurring noble gas and poses a significant, hidden health hazard when it accumulates inside poorly ventilated enclosed spaces.
In more detail
Radon resides in group 18 of the periodic table and is continuously formed by the natural radioactive decay of radium, which itself is a decay product of uranium and thorium naturally found in global soils and rocks. Being a noble gas, radon is remarkably chemically inert under standard conditions, but it can form a few simple chemical compounds, such as radon difluoride (RnF2), under extreme laboratory conditions. The gas easily diffuses out of the ground and into the atmosphere, where it can accumulate and concentrate heavily in building basements, underground mines, and sealed houses. The most stable natural isotope is radon-222, possessing a half-life of about 3.8 days, which predictably decays into solid radioactive elements that can be deeply inhaled. Prolonged exposure to concentrated radon and its radioactive decay products is recognized as a leading global cause of lung cancer.
Key facts
| Field | General Chemistry |
|---|---|
| Symbol | Rn |
| Atomic number | 86 |
| Atomic mass | [222] u |
| Category | Noble Gas |
| State at room temperature | Gas |
| Boiling point | -61.7 °C (-79.1 °F) |
| Year discovered | 1899 |
| Discoverer | Ernest Rutherford and Robert Owens |
Radon gas naturally seeps continuously from uranium-bearing soil and underlying bedrock into household basements, necessitating the widespread use of active mitigation ventilation systems in severely affected residential homes.
Frequently asked questions
Why is radon gas dangerous if it is chemically inert?
The danger of radon completely originates from its radioactivity rather than its chemistry; it decays into heavy solid radioactive particles that permanently lodge in the lungs and emit DNA-damaging alpha particles.
How can a homeowner detect radon inside a building?
Since radon gas is entirely invisible and odorless, it can only be accurately detected using specialized short-term or long-term radon test kits that sensitively measure local radiation levels.