The graph shows the binding energy per nucleon versus mass number. $A, B, C, D, E, F$ are different nuclei. Four processes are given where $\varepsilon$ is the energy released. In which process is $\varepsilon > 0$?
$(i) \, A + B \rightarrow C + \varepsilon$
$(ii) \, C \rightarrow A + B + \varepsilon$
$(iii) \, D + E \rightarrow F + \varepsilon$
$(iv) \, F \rightarrow D + E + \varepsilon$

In nuclear reactions,which of the following quantities are conserved?

The binding energy of nucleons in a nucleus can be affected by the pairwise Coulomb repulsion. Assume that all nucleons are uniformly distributed inside the nucleus. Let the binding energy of a proton be $E_b^p$ and the binding energy of a neutron be $E_b^n$ in the nucleus. Which of the following statement(s) is(are) correct?
$(A)$ $E_b^p - E_b^n$ is proportional to $Z(Z-1)$ where $Z$ is the atomic number of the nucleus.
$(B)$ $E_b^p - E_b^n$ is proportional to $A^{-1/3}$ where $A$ is the mass number of the nucleus.
$(C)$ $E_b^p - E_b^n$ is positive.
$(D)$ $E_b^p$ increases if the nucleus undergoes a beta decay emitting a positron.

In the nuclear reaction,$_1H^2 + _1H^2 \to _0n^1 + _2He^3$. If the binding energy of deuteron is $2.23 \ MeV$ and the $Q$-value of the reaction is $3.27 \ MeV$,then the binding energy of $_2He^3$ is ......... $MeV$.

The mass of a $_3^7Li$ nucleus is $0.042 \, u$ less than the sum of the masses of its constituent nucleons. The binding energy per nucleon of the $_3^7Li$ nucleus is approximately ......... $MeV$.

The positions of four different nuclei in the binding energy curve are shown in the figure. The process that might not proceed spontaneously is