Q19 of 26 Page 1

(a) The figure shows the plot of binding energy (BE) per nucleon as a function of mass number A. The letters A, B, C, D and E represent the positions of typical nuclei on the curve. Point out, giving reasons, the two processes (in terms of A, B, C, D and E), one of which can occur due to nuclear fission and the other due to nuclear fusion.

1.PNG


(b) Identify the nature of the radioactive radiations emitted in each step of the decay process given below.


(a) As mass number of E is much larger and binding energy per nucleon for C and D is larger, nuclear fission of E into C and D can occur.


As mass number for A and B is small and binding energy per nucleon for C is much larger, nuclear fusion of A and B into C can occur.


(b) First step is an alpha decay reaction. Therefore, α rays will be emitted.


Second step is a beta minus decay reaction. Therefore, β- rays will be emitted.


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