The nucleus of a radioactive element emits an `alpha`-particle and then emits 2 `beta`-particles subsequently . Prove that the product (daughter nucleus ) is actually an isotope of the original elements .

Explanation

According to the law of radioactivity , if an `alpha`-particle is emitted from an element atomic number decreases by 2. Again, if `beta`-particle is emitted it increases by 1. So if a particular nucleus of an element emits an `alpha`-particle and then `2 beta`- particles , the change in its atomic number =(-2+1+1)=0.
Again isotopes are elements having equal atomic number but different mass numbers. So the daughter nucleus is an isotope of the parent one.