Radon is a naturally occurring element and is found in soil, igneous rock, and in some cases water.
Radon is a cancer causing radioactive gas and it is shown that 20,000 lung cancer deaths each year are caused by radon. Radon is nine times more dense than normal oxygen.
Properties: At room temperature radon is basically colorless. At below freezing point, it is a bright yellow, but still nonreactive.
Use: Like many radioactive things, radon can also have a good and practical use. It is used in some medicines and some spas also use it for some presumed medicinal effects. Mostly radon, when it decays it turns into polonium and alpha particles, is used for effective cancer therapy.
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