If an element has too many or too few of what the element becomes unstable and will decay or not form at all?

1 Answer
May 16, 2017


If an element has too many or too few neutrons, the element becomes unstable and will decay.


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 the periodic table, 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 elements (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 #alpha#-decay and has a positive charge.

When electrons fall off, we have #beta# rays with a negative charge.

Sometimes, energy is given off as the nucleus tries to become more stable. This energy is called #gamma# radiation and does not have a charge.

Here's a video with details: