Chemically speaking, radon is a colourless, odourless, and tasteless radioactive noble gas. This gas is produced by the decay of radium, which can be found in a number of common minerals such as uranium and/or phosphate ores. Almost all rocks contain at least some concentration of uranium, typically around 1 – 3 ppm (Michaela Kreuzer, 2010). Radon gas, when released from rock and soil, undergoes radioactive decay to produce a series of progeny.
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