Answer:
In the quantum-mechanical model of an atom, electrons in the same atom that have the same principal quantum number (n) or principal energy level are said to occupy an electron shell of the atom. Orbitals define regions in space where you are likely to find electrons.
Mass defect and binding energy are related as
ΔE = Δmc^2
Where
ΔE = binding energy
Δm = mass defect
c = speed of light
given
mass defect = 3.09x 10-27 kg
We know that speed of light = 3 X 10^8 m /s
ΔE = 3.09x 10-27 kg (3 X 10^8 m /s)^2 = 2.781 X 10^-10 J / Kg
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