Calculate the binding energy per nucleion of `Li` isotiope, which has the isotopic mass of `7.016 am u`. The indivisulal masses of netutron and proton are `1.008665 am u` and `1.007277 am u`, respectively and the mass of electron `= 0.000548 am u`.

Explanation

The total energy given out as mass decay during binding up of nucleons is known as binding energy.
Mass of `._(3)Li^(7)` isotope `= 7.016` amu
Mass of 3 protons in it `= 3xx1.007277 = 3.022` amu
Mass of 4 neutrons in it `= 4xx1.008665 = 4.035` amu
Mass of 3 electrons in it `= 3xx0.00548 = 0.008` amu
`:.` Mass defect `= [3.022+4.035+0.002] - 7.016`
`= 0.043` amu
`Delta E = 931.478xx Delta m' MeV`
`= 0.043xx931.478 = 40.0 MeV`
`:.` Binding energy per nucleon `= (40//7) = 5.71 MeV`