Calculate the energy equivalent of $1 \ g$ of substance.

The mass of ${ }_7 N ^{15}$ is $15.00011 \ amu$,the mass of ${ }_8 O ^{16}$ is $15.99492 \ amu$,and $m_p = 1.00783 \ amu$. Determine the binding energy of the last proton of ${ }_8 O ^{16}$ in $MeV$.

The energy equivalent of $0.5\, g$ of a substance is $........\, J$.

Mass numbers of the elements $A, B, C$ and $D$ are $30, 60, 90$ and $120$ respectively. The specific binding energies of them are $5 \text{ MeV}, 8.5 \text{ MeV}, 8 \text{ MeV}$ and $7 \text{ MeV}$ respectively. In which of the following reaction$(s)$ is energy released?
$1. D \rightarrow 2B$
$2. C \rightarrow B + A$
$3. B \rightarrow 2A$

$A$ nucleus $^{A}_{Z} X$ has mass represented by $M(A, Z)$. If $M_p$ and $M_n$ denote the mass of a proton and a neutron respectively, and $B.E.$ is the binding energy in $MeV$, then:

When the atomic number $A$ of the nucleus increases,