What is Radioactivity and Is It Always Harmful: Explained in Really Simple Words

Radioactivity is the property through which a heavier, unstable nucleus assumes a more stable state by emitting radiation. The process through which a nucleus turns into a stable one is called radioactive decay. But is radioactivity or radioactive radiation always harmful? Let’s discuss this in more detail. Inside an atom’s nucleus, there are positively charged protons and neutral neutrons. These nucleons are held together by a “glue” called the strong nuclear force. This strong force cancels out the repulsive electrostatic force of like charged protons and keeps the nucleus stable. The nuclear force has a short range of action and is dependent on the ratio of neutrons and protons present in a nucleus. However, we see that the balance between the forces starts to waver in a nucleus where the number of neutrons exceeds the number of protons. A nucleus that exceeds the threshold number of neutrons and protons that the strong nuclear force can hold together comfortably will be more unstable. More specifically, these scenarios give rise to unstable isotopes of elements. Just as your body, through a series of expansions and contractions, expels a substance with a sneeze, similarly, the unstable isotopes of elements fling out different particles or forms of energy to restore balance between the forces in their nucleus. During this process of attaining stability, they change into a new nucleus. It is exactly this property, namely turning into something new to attain stability, that we call radioactivity.