Define Binding energy of the nucleus. Draw and explain curve between Binding Energy per nucleon and mass number.

Explanation

Binding energy Curve between binding energy per nucleon and mass number : Variation of binding energy per nucleon with mass number

From the binding energy curve shown in Fig., we observe that:
(i) Averge binding energy per nucleon is small for nuclei like
(ii) except for some nuclei like average binding energy per nucleon lies on a smooth curve.
(iii) For mass numbers ranging from 2 to 20, there are well defined maxima and minima on the curve. Maxima occurs for etc. These peaks indicate that these nuclei are morestableihan their neighbours. Minima corresponds to low stability and are for I Li, etc. nuclei.
(iv) Binding energy curve has a broad maxima of about 8-5 MeV/nucIeon in the, mass number range from 30 to 120. It is independent of the size of the nucleus. This observation gives us the idea about the strength of nuclear force. Peak value is 8-8 MeV per nucleon for
(v) .On further increasing the mass number, there is a gradual decrease in B.EVnucleon and it drops to 7-6 MeV/nucleon for This is because of Coulomb.s repulsion between the protons inside the nucleus.
(vi) B.E. is low for both, very light nuclei `(Zlt 10)` and very heavy nuclei `(Zgt 70)`. This