Large atomic nuclei can indeed become unstable due to the limited range of the strong force. The strong force is responsible for holding the nucleus of an atom together by overcoming the electromagnetic repulsion between protons. However, the strong force has a limited range and becomes weaker as the distance between nucleons (protons and neutrons) increases.
In larger atomic nuclei, as the number of protons and neutrons increases, the repulsive electromagnetic forces between the protons become stronger. At the same time, the attractive strong force becomes less effective at overcoming this increasing electromagnetic repulsion. This can lead to an unstable nucleus that is prone to decay or undergo nuclear reactions.
One factor that can contribute to nuclear instability is the neutron-to-proton ratio. Nuclei with a high neutron-to-proton ratio, such as those found in very heavy elements, can become unstable. These nuclei may undergo radioactive decay processes, such as alpha decay or spontaneous fission, in an attempt to reach a more stable configuration.
The stability of atomic nuclei is a complex topic influenced by various factors, including the interplay of fundamental forces, nuclear shell structure, and the overall energy balance within the nucleus. While the limited range of the strong force is a contributing factor to the instability of large atomic nuclei, it is not the sole determinant.