What are Radioactive Isotopes?

Radioactive Isotopes aka Radioisotopes, are unstable isotopes of an element. These isotopes emit radiation in the form of radioactive decay. Most radioisotopes are created through nuclear reactions, such as those that occur in nuclear reactors or particle accelerators. But some radioisotopes occur in nature such as carbon-14 and uranium-238. These isotopes go through the process of radioactive decay to form more stable nuclei and emit alpha, beta and gamma radiation during the decay. These emissions of radiation took place over a very short period of time or over millions of years, depending on the half-life of the isotope.

Isotopes of Uranium

Uranium is a naturally occurring radioactive element found in nature that has many isotopes but no isotope is stable in nature. But some of these radioactive isotopes have a significant half-life (in order of million years). Also, it has two primordial isotopes i.e., U-235 and U-238, out of which U-238 is the most abundant isotope on earth and has the most half-life as well. Therefore it is used in research and nuclear applications.

Application of Radioactive Isotopes

The following are the important uses of Radioactive Isotopes:

• Radioactive Dating: Radiocarbon dating, which determines the age of carbon-bearing objects, uses the radioactive isotope carbon-14. Because radioactive isotopes’ half-lives are unaffected by external variables, the isotope functions as an internal clock.
• Irradiation of Food: Some radioactive compounds produce radiation that may be used to destroy germs on a range of goods, therefore prolonging their shelf life. Tomatoes, mushrooms, sprouts, and berries are all irradiated with cobalt-60 or cesium-137 emissions.
• Medical Applications: Radioactive isotopes offer a wide range of medicinal uses, including the diagnosis and treatment of sickness and disease. For example, ³²P is utilized for cancer identification and therapy, particularly in the eyes and skin, ⁵⁹Fe for anaemia diagnosis, ⁶⁰Co for tumor gamma-ray irradiation, ¹³¹I for thyroid function diagnosis and treatment, and many more uses.
• Other uses: Radioactive isotopes find uses in agriculture, the food industry, pest control, archaeology, and medicine. 

Isotopes are those atoms that are having the same atomic number or the same position in the modern periodic table but with different atomic masses. This difference in atomic mass arises from the different numbers of neutrons present in the nucleus of the atom. As they lie in the same position on the periodic table they almost have similar chemical properties but different physical properties due to the difference in atomic mass. Other than Isotopes, there are isobars, and isotones are also defined based on the number of subatomic particles in the atom.