The Student Room Group

Mass-Energy in Fission

1. Each of the following are possible fission fragments when a nucleus of uranium -235 (23592U) absorbs a slow neutron 10n.

For each, by writing and balancing the full nuclear reaction, determine the number of neutrons that are produced from the fission.

a) 141 56 Ba and 9236 Kr



b) 14054Xe and 9438Sr



c) 14357La and 9035Br



d)13755Cs and 9637Rb



e)13153I and 8939 Y



2. Use the graph of binding energy per nucleon to estimate the total binding energy for a nucleus of each of the 10 fission fragments above (in eV)



3. Hence, determine the energy released in Joules for each of the 5 fission reactions a)-e)



4 (a) State what is meant by the binding energy of a nucleus.



(b) (i) When a 235 92U nucleus absorbs a slow-moving neutron and undergoes fission one possible pair of fission fragments is technetium 112 43 Tc and indium 122 49 In .

Complete the following equation to represent this fission process.



10n + 235 92 U -----> 112 43 Tc + 122 49 In + ................



(ii) Calculate the energy released, in MeV, when a single 235 92 U nucleus undergoes fission in this way.



binding energy per nucleon of 235 92 U = 7.59 MeV

binding energy per nucleon of 112 43 Tc = 8.36 MeV

binding energy per nucleon of 122 49 In = 8.51 MeV





(iii) Calculate the loss of mass when a 235 92 U nucleus undergoes fission in this way.



loss of mass ......................................... kg
(edited 1 year ago)
Reply 1
1. Each of the following are possible fission fragments when a nucleus of uranium -235 (23592U) absorbs a slow neutron 10n.

For each, by writing and balancing the full nuclear reaction, determine the number of neutrons that are produced from the fission.

a) 141 56 Ba and 9236 Kr



b) 14054Xe and 9438Sr



c) 14357La and 9035Br



d)13755Cs and 9637Rb



e)13153I and 8939 Y



2. Use the graph of binding energy per nucleon to estimate the total binding energy for a nucleus of each of the 10 fission fragments above (in eV)



3. Hence, determine the energy released in Joules for each of the 5 fission reactions a)-e)

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