Observation

Part (a) (i): This question was popular among the candidates but unfortunately performance was poor. Candidates last mark due to the fact that neutron was not mention as one of the products of nuclear fission.
           (ii): Candidates lost some marks because of vagueness in stating the functions of the materials. Performance was low.

Part (b)(i):       The question was poorly attempted by many candidates. Energy levels/lines were not correctly spaced and labelled.
(ii): Many candidates were able to write down the formula but a good number did not convert Energy to joules in the substitution.

Part (c): All except very few attempted this part and majority of the candidates got it wrong. Performance was low.

The expected answer is: