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Applications of Radioactivity

Last updated date: 21st Feb 2024
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Radioactivity Meaning

Radioactivity is the emission of ionizing radiation or particles as a result of the disintegration or breakdown of atomic nuclei.

Wherever there is a nuclear instability, the atom’s nucleus undergoes the phenomenon of radioactivity. The radioactivity results in nucleus decay.

Wherefore, the unstable nuclei spontaneously decay into their most stable configuration by emitting certain particles or in the form of electromagnetic radiation.

In the present time, radioactivity, such as radioisotopes has various applications in diagnosis and therapy.

This page discusses in-depth the uses of radioactive substances with the application of radioactivity.

What is Radioactivity?

Many day-to-day activities in nature take place around us that we are unaware of. 

Further, processes like emission and absorption are some of the phenomena that take place unknowingly.

When emission or absorption takes place in the atom. This is the place where a stable property of nature comes, we call this stability the Radioactivity.

Radioactivity is one of the scientific properties of matter where the emission of supersonic subatomic particles takes place spontaneously. 

On this page, we will focus more on the two following things:

  • Uses of radioactivity

  • Application of radioactivity

Application of Radioactive Isotopes

Radioisotopes have a wide range of use in diagnosis and therapy.

Further, this has led to a rapidly growing field named nuclear medicine. 

The radioactive isotopes are perfectly effective as tracers in certain diagnostic procedures. 

Ordinarily, radioisotopes are chemically alike to stable isotopes of the same element.

Because of this reason, they can take the place of the latter in physiological processes. 

Moreover, detection devices as gamma-ray spectrometers and proportional counters can readily trace the radioisotopes even in minute quantities.

Though many radioisotopes likewise iodine-131, phosphorus-32, and technetium-99m are among the most important tracers. 

Applications of Radioactivity

1. In Medicines

Physicians find iodine-131, the best radioisotope for determining the following:

  • Cardiac output

  • Plasma volume

  • Fat metabolism 

  • Particularly, to measure the activity of the thyroid gland where this isotope piles up.

Physicians also use Phosphorus-32 for identifying malignant tumours. It’s because cancerous cells accumulate phosphates more than normal cells do. 

Additionally, Technetium-99m is also used with radiographic scanning devices. 

Technetium-99m radioisotopes are also rich for examining the anatomic structure of organs.

Moreover, radioisotopes like Cobalt-60 and cesium-137 are used to treat cancer. 

Also, they can administer malignant tumours to minimize damage to adjacent healthy tissue.

Furthermore, there are other uses of radioactive substances that we will discuss:

2. Industrial Use

For the most part, radioactivity has the most important industrial applications in power generation as a result of the release of the fission energy of uranium. 

Other applications include the use of radioisotopes to measure/control the thickness/density of metal and plastic sheets.

Industrialists also find uses of radioactive substances in the following works:

  • Firstly, to stimulate the cross-linking of polymers.

  • Secondly, to induce mutations in plants to develop harder species.

  • Thirdly, to preserve certain kinds of foods by killing microorganisms that cause spoilage. 

  • Lastly, in tracer applications, radioactive isotopes are employed. 

For instance,  in automobile engines, we find the uses of radioactive substances measuring the effectiveness of motor oils on the wearability of alloys for piston rings and cylinder walls.

Use of Radioactivity

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Research in the Earth sciences has benefited scientists greatly by the use of radiometric dating techniques. 

These techniques rely on the principle that a particular radioisotope (radioactive parent) in geologic material decays at an invariant known rate to daughter isotopes. 

Using such techniques, investigators have determined the ages of various rocks and rock formations and thereby quantified the geologic time scale, also known as Absolute dating. 

Carbon Dating

A special application of this type of radioactivity age method is carbon-14 dating, This application has proven to be useful especially to physical anthropologists and archaeologists. 

Additionally, it has helped researchers to better determine the chronological sequence of past events by enabling them to date more accurately fossils and artifacts from 500 to 50,000 years old.

Radioisotopic Tracers

Radioisotopic tracers are very helpful in environmental studies. For instance, studying water pollution in rivers and lakes and air pollution by smokestack effluents. 

They are also used to measure deep-water currents in oceans and snow-water content in watersheds. 

Researchers in the biological sciences, too, make maximum use of radioactive tracers to study complex processes. 

For instance, thousands of plant metabolic examinations are conducted on amino acids and compounds of sulfur, phosphorus, and nitrogen.

Application of Radiochemistry

Radiochemistry uses radioisotopes to primarily deal with the study of chemical reactions of non-radioactive isotopes.

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Besides this, it finds application in the medical field and environmental management. 

The Important Applications of Radioisotopes are:

Radiocarbon Dating: This method helps determine the age of fossil wood or animal by using the C -14 isotope.

Study of Chemical Reactions: By mixing a radioisotope with a non-radioactive isotope of the reactants, the nature of some of the chemical reactions can be studied. 

The radioisotope used for this purpose is a radiotracer. 

For example, by photosynthesis plants synthesize carbohydrates from carbon dioxide and water as described in the following reaction.

             12 CO2                 +            12 H2O    →  produces →      2 C6H12O6     +     12 O2

             Carbon dioxide                Water                                        Sugar               Oxygen

Here, a question arises: did the oxygen evolved in this process come from CO2 or H2O?. However, by using radioisotope O -18 as a tracer, we find that the evolved oxygen comes from H2O.

FAQs on Applications of Radioactivity

1. State the Laws of Radioactivity. Also, State the Unit of Radioactivity.

Ans: The laws of radioactivity are as follows:

Radioactivity occurs as a result of the nucleus decay.

The rate of decay of the nucleus does not depend on the temperature and pressure.

Radioactivity depends on the law of conservation of charge.

The physical and chemical properties of the daughter nucleus vary from the mother nucleus.

The energy emitted by radioactivity is always accompanied by alpha, beta, and gamma particles/rays.

The rate of decay of radioactive substances depends on the number of atoms present at the time.

Units of radioactivity are Curie and Rutherford.


1C = 3.7 × 104 Rd. This is the relationship between the two units, i.e., Curie and Rutherford.

2. State the Merits and Demerits of Radioactivity.

Ans: The merits and demerits of radioactivity lie hereunder:


Gamma rays are used in radiotherapy to treat cancer patients.

A radioisotope, Cobalt-60 is used to destroy cancer cells.

Doctors use gamma rays for scanning the internal parts of the patient

Gamma rays help kill microbes present in food and prevent decaying the food by increasing the shelf life.

The age of the rocks can be determined using radioactive radiations by measuring the quantity of argon present in the rock.


Radioisotopes are very expensive.

Though radioactive substances treat cancerous cells; however, if these rays enter the neighbouring tissues it can damage them.

High intake of radioactive substances may lead to death.

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