Isotope and radioisotope are different .
Isotopes are atoms of a same element which have same number of protons but different number of neutrons .
Radioisotope is a isotope which is radioactive in nature that means after a certain period of time the radioisotope will decay ,give out energy . This happens because the isotope contains unequal numbers of protons and neutrons ( that's why they decay ).
Radioisotope can be use to treat cancer and to check for leaks .
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