Add yet another neutron to the nucleus so that the mass number is 14.Determine whether the nucleus is stable or unstable.StableUnstable

To answer this question, we first need to know which element we are dealing with. The mass number is the total number of protons and neutrons in an atom's nucleus. If we add another neutron and the mass number becomes 14, it means the element had a mass number of 13 before the addition.

However, without knowing the number of protons (which defines the element), we cannot determine whether the nucleus is stable or unstable. The stability of a nucleus is determined by the ratio of neutrons to protons. Certain ratios result in more stable nuclei.

If we know the element or the number of protons, we can then look at the known isotopes of that element. If an isotope with that specific number of neutrons (resulting in a mass number of 14) exists and is stable, then the nucleus would be stable. If not, it would be unstable.

So, without more information, we cannot definitively answer this question.