Question

Draw a plot of BE/A versus mass number A for 2 ≤ A ≤ 170.Use this graph to explain the release of energy in the process of nuclear fusion of two light nuclei.

Answer 1

The above curve shows that

(i) When a heavy nucleus breaks into two medium sized nuclei (in nuclear fission), the BE / nucleon increases

resulting  in the release of energy. 

(ii) When two small nuclei combine to form a relatively bigger nucleus in nuclear fusion, BE / nucleon increases, resulting in the release of  energy.