Question

Why is the number of neutrons greater than the number of protons in stable nuclei that
have an A > 40? Why is this effect more pronounced for the heaviest nuclei?

Answer 1

In a cell there is a nucleus inside that there are many protons and neutrons and outside nucleus there are electrons

Answer 2

Answer:

The number of neutrons are greater than the number of protons in stable nuclei because of the following reason:

• H-1 and He-3 have protons more than neutron.

• Due to long range electrostatic force, Protons within nucleus repel. Alone protons cannot bind them-self even there exist nuclear attractive force between protons.
• This happens due to short range and saturated nature of nuclear forces. To provide protective shield to proton from other protons within nucleus, the larger number of neutrons are required.

• In a heavier nucleus, the repulsive force between the protons is extremely high and to provide stability, the nuclear force must dominate this electrostatic repulsive force.
• The nuclear force can dominate the electrostatic repulsive force if the number of neutrons is greater than number of protons.