Find the energy released in the reaction 1H2+1H2→2He4 if binding energy per nucleon for deuteron and α particles are x1 and x2, respectively.

The binding energy on reactant side (i.e., deutrons) is 4×x1=4x1The binding energy on product side (i.e., α-particle) is 4×x2=4x2So, energy released Q is4x2−4x1=4x2−x1