Question

In most stable nuclei, neutron number $N$ and proton number $Z$ has the relation

• A. $N=Z$
• B. $N>Z$
• C. $N<Z$
• D. $N⩾Z$

Answer 1

The correct option is D $N⩾Z$

For lighter stable nuclei, $N=Z$,

But for heavier stable nuclei, to overcome the factor of electrostatic force of repulsion, the number of neutrons will be greater than the number of neutrons,

So for heavier stable nuclei, $N>Z$.

Therefore, in general, for stable nuclei, $N⩾Z$

Hence, option $\left(D\right)$ is correct.