Question

Radon gas is a radiological health hazard to the general population because

a. it is an alpha-emitting noble gas and is widespread because it is a descendant of U-238 which is plentiful in our planet.

b. one gram of radium has activity very nearly equal to 1 Ci.

c. it is used in fluorescent lamps.

d. it is formed in the atmosphere by cosmic rays and everyone breathes the resulting unstable nuclei.

e. it irradiates lung tissue with β^- particles.

Answer 1

Radon is an element with atomic number 86 and chemical symbol Rn. It is a so-called “inert” gas, which means that the element radon does not readily react with other substances. However, radon gas is radioactive and decays naturally. When the radon decays, it emits ionising radiation containing alpha particles.

Ionisation removes electrons from an atom by means of radiation. Atoms, which were previously in equilibrium, then become charged ions which are able to react with other atoms or ions. Such reactions can damage and/or alter a DNA molecule and cause mutations or cancer or can kill cells. For that reason, ionising radiation, and therefore radon, is dangerous to humans.

So answer (b) is correct.

Because it's decay rate is very high.