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A nucleus of mass number 200 breaks into two fragments with mass numbers 80 and 120. The binding energy per nucleon for the parent nucleus is 6.5 MeV, while for the two daughter fragments it is 7 MeV and 8 MeV respectively. What is the energy released (in MeV) in this nuclear fission?
- 50
- 100
- 150
- 200
Correct answer: 200
Solution
Binding energy of parent = 200 x 6.5 = 1300 MeV. Binding energy of fragment of mass 80 = 80 x 7 = 560 MeV. Binding energy of fragment of mass 120 = 120 x 8 = 960 MeV. Energy released = (560 + 960) - 1300 = 1520 - 1300 = 220 MeV. Closest option is 200 MeV.
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