Let us first find the B.E. of each copper nucleus and then we can find binding energy of 300 g of

63

‌

29

Cu
Mass of 29 protons = 29 × 1.00783 = 29.22707 u
Mass of 34 neutrons = 34 × 1.00867 = 34.29478 u
Total theoretical mass = 63.52185 u
Actual mass of Cu nucleus = 62.92960 u
Mass of defect = Theoretical mass – Actual mass = 0.59225 u
B.E. of each Cu nucleus = Δm [931.5 MeV]
= 0.59225 [931.5 MeV] = 551.385 MeV
Number of atoms in 3 g of copper
n =

Avagadro‌number

Mass‌Number

× 3 or n =

6.023×1023×3

3

= 2.8 × 1022
Total binding energy in 3 g of copper
= 2.86 × 1022 × 551.385 MeV = 1.6 × 1025 MeV
So, the energy required to separate all the neutrons and protons from each other in 3 g copper coin will be 1.6 × 1025 MeV.