Nuclear Fission


(a) In the reactor at a nuclear power station, uranium nuclei undergo induced fission with thermal neutrons. Explain what is meant by each of the terms in italics.

(3 marks)

(b) A typical fission reaction in the reactor is represented by:

+ + +

(i) Calculate N.

(ii) How do the neutrons produced by this reaction differ from the initial neutron that goes into the reaction?

(iii) Calculate the energy released in MeV when one uranium nucleus undergoes fission in this reaction.


Use the following data:

mass of neutron = 1.00867 u

mass of 235U nucleus = 234.99333 u

mass of 92Kr nucleus = 91.90645 u

mass of 141Ba nucleus = 140.88354 u

(5 marks)

(Total 8 marks)