Question

The figure below shows features of a diffusion cloud chamber used for detecting radiations from a radioactive source.

1. Explain how the chamber works when a radioactive particle is introduced at the source.
2. What is the purpose of solid carbon (IV) oxide. 
3. State one advantage of the cloud chamber over a G.M tube as a detector of radioactive radiations.

Answer 1

1. Explain how the chamber works when a radioactive particle is introduced at the source. 
   • The radiations ionize argon gas along their path. The alcohol vapour condense on the ions formed creating tracks.
2. What is the purpose of solid carbon (IV) oxide. 
   • Lower the temperature in the chamber thus making it possible for the alcohol vapour to condense.
3. State one advantage of the cloud chamber over a G.M tube as a detector of radioactive radiations. 
   • The nature of the radiation can be identified