Q.Calculate the mass defect, the total binding energy, and the binding energy per nucleon of $^{16}_{8}\text{O}$, given: mass of $^{16}_{8}\text{O}$ atom $= 15.994915\ \text{u}$, mass of hydrogen atom $= 1.007825\ \text{u}$, mass of neutron $= 1.008665\ \text{u}$.

For $^{16}_{8}\text{O}$, $Z=8$ protons and $A-Z=8$ neutrons. The mass defect is

The total binding energy is

and the binding energy per nucleon is …

Compute $\Delta m$ from the mass of the separate nucleons minus the actual nuclear mass, convert to $BE$ using $931.5\ \text{ …

• Using the neutron and hydrogen masses the wrong way round (e.g. using neutron count $=8$ but multiplying by the hydrogen mass instead). …