Problem: Calculate the quantity of energy produced per gram of U-235 (atomic mass = 235.043922 amu) for the neutron-induced fission of U-235 to form Xe-144 (atomic mass = 143.9385 amu) and Sr-90 (atomic mass =89.907738 amu).

We’re asked to calculate the quantity of energy produced per gram of U-235  for the neutron-induced fission of U-235 to form Xe-144  and Sr-90.

Recall that Nuclear Fission is the splitting of a heavy nucleus to form two or lighter ones.

Neutron-induced fission is when you shoot a neutron particle at the nucleus and that’s what splits the nucleus into smaller ones. Therefore, a neutron is one of the reactants.

To calculate the energy produced for the reaction per gram of U-235, we’re going to use the following steps:

Step 1: Write a balanced nuclear reaction
Step 2: Calculate the mass defect (Δm).

Step 3: Calculate the mass defect (Δm) in kg.
Step 4: Calculate the energy produced (E).

Step 1: Write a balanced nuclear reaction

Reactants: U-235 and neutron

Products: Xe-144  and Sr-90

*The numbers denote the mass number of each element  

Reaction:

${}_{\mathbf{92}}{}^{\mathbf{235}}\mathbf{U}\mathbf{+}{}_{\mathbf{0}}{}^{\mathbf{1}}\mathbf{n}\mathbf{\to }{}_{\mathbf{54}}{}^{\mathbf{144}}\mathbf{Xe}\mathbf{+}{}_{\mathbf{38}}{}^{\mathbf{90}}\mathbf{Sr}$

*The numbers written below the mass numbers are the atomic numbers of each element and can be found on the periodic table.