What is radon?

Radon is the chemical element of atomic number 86, a rare radioactive gas belonging to the noble gas series. Radon is a cancer causing radioactive gas. You can't see, smell or taste radon. Radon is a colorless chemically-un reactive inert gas. Radon is the only gas under normal conditions that only has radioactive isotopes. Radon relates to nuclear chemistry through the decay chains, it was discovered through a decay chain.