Shielding of protons from each other with neutrons plays a big role in the stability of the nucleus. Although the distances are pretty tiny, the separation. Shielding of protons from each other with neutrons plays a big role in the stability of the nucleus. Although the distances are pretty tiny, the separation provided by the neutrons stabilizes the element by lowering the potential energy. Since the potential energy equals Ze^2/kr, where Z is the nuclear charge, e is the charge of the proton, k a constant, and r the distance between the protons, any increase in r will stabilize the nucleus by a high amount.
Empirically it seems that the best separation occurs when there are 1-2 neutrons per proton. Anything less than that makes the nucleus unstable towards electron-capture or positron emission. No protons are ejected as a result of nuclear instability, as it was suggested prior to this post.
Radiation occurs when energy or parts of atoms are given off by radioactive atoms. The nucleus of an atom contains protons and neutrons. If you look at the periods (rows) with smaller numbers on, you will find that the number of protons and neutrons are the same. The neutron:proton ratio is 1:1.
As you move to the higher periods, there are a small number of protons compared to neutrons. The neutron:proton ratio is 1:1. 5. The nucleus wants to shoot apart because of all the positive charges in close proximity. The nucleus is held together by the strong nuclear force, but this force works only at extremely small distances. In smaller period (e. g. , Neon), the strong nuclear force is strong enough to hold the elements together. However, in larger period elements (e. g. , uranium), the average distance between protons and neutrons is too great. The strong nuclear force can no longer hold the nucleus together.
Thus, there is a delicate balance between protons, neutrons, and the strong nuclear force. When the proton:neutron ratio is less than 1:1 or greater than 1. 5:1, the atoms give off protons, neutrons, electrons, and energy until they become stable. When protons-neutron pairs fall off, that is called -decay and has a positive charge. When electrons fall off, we have rays with a negative charge. Sometimes, energy is given off as the nucleus tries to become more stable. This energy is called radiation and does not have a charge.