For a nucleus to be stable, the correct relation between neutron number `N` and proton number `Z` is.

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

Answer the following questions in one sentence each : State the relation between the number of protons, the number of neutrons and the atomic mass number (A) of an element.

Is there any relation between the total number of protons and neutrons in an atom and its mass?

A : During radioactive disintegration an alpha -particle and a beta -particle do not emit simultaneously from any nucleus. R : An alpha -particle emits from a nucleus when the N/Z ratio is less than the stability range (where N=number of neutrons and Z=number of protons in a nucleus. )

A : During radioactive disintegration an alpha -particle and a beta -particle do not emit simultaneously from any nucleus. R : An alpha -particle emits from a nucleus when the N/Z ratio is less than the stability range (where N=number of neutrons and Z=number of protons in a nucleus. )