To calculate the energy released when two deuterons ( ) fuse to form a helium nucleus , consider the following:

The reaction is represented as:

Given the binding energy per nucleon:
For
For
Calculating Binding Energy
Binding Energy for Reactants:

Each deuteron ( ) has a binding energy of 1.1 MeV per nucleon.

Since there are two nucleons in a deuteron, the total binding energy for one deuteron is .

Therefore, for two deuterons:

Binding Energy for Product:
For : Each of the four nucleons has a binding energy of 7.0 MeV.

Total binding energy for the helium nucleus:

Energy Released (Q)
The energy released, Q, is the difference between the binding energy of the products and the reactants:

Thus, the energy released when two deuterons fuse to form a helium nucleus is 23.6 MeV.