Question

What is (a) mass defect, and (b) binding energy in Oxygen ${}_8^{16}O$, whose nuclear mass is $15.995$ amu. $(m_p=1.0078$amu$;$ $m_n=1.0087$amu$)$.

Answer 1

Oxygen ${}_8^{16}O$ has $8$ protons and $8$ neutrons.

Nuclear mass of ${}_8^{16}O$, $M_N=15.995$ amu

(a) Mass defect, $\Delta M=8m_p+8m_n-M_N$

$\therefore$ $\Delta M=8\left(1.0078\right)+8\left(1.0087\right)-15.995=0.137$ amu

(b) Binding energy, $E=\Delta M\times 931.5$ MeV

$⟹$ $E=0.137\times 931.5=127.62$ MeV