A vessel has two compartments connected at the top. In one compartment (B), radioactive methyl iodide (CH₃I) is placed and in the other (A) normal methyl iodide (CH₃I) is placed. Will the vaporus over (A) and (B) become radioactive?
Will the radioactivity spread to the liquid in the compartment A? Discuss in terms of dynamic nature of the equilibrium between vapours and its liquid.

(i) Yes, the vapours over both the compartments A and B will become radioactive. This is because the vapours formed over A and B can diffuse into each other.

(ii) Yes, the radioactivity will also spread to the liquid in the compartment A. This is because equilibrium is dynamic in nature i.e. processes of evaporation and condensation continue at equal rates even after the attainment of equilibrium as the space above the compartments A and B contains vapours of both radioactive CH₃I and nonradioactive CH₃I. Now the vapours of radioactive CH₃I will condense in compartment A, thereby making the liquid in compartment A radioactive.