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Laws of Radioactivity

Radioactivity is the phenomenon where a material emits radiation over a period of time after being bombarded with particles. This article discusses the Laws of Radioactivity.

Radioactivity is the transfer of energy from the nucleus of an atom that is in the process of being made to another atom. The laws of radioactivity describe the conditions that make radioactivity possible. As previously mentioned, radioactivity is a process in which an atom or nucleus splits into two or more subatomic particles. This is accomplished by the emission of an ionising event from an atomic or nuclear reaction. Radioactivity laws state that radioisotopes are inherently dangerous because they are unstable and decay in the presence of oxygen.

What is Radioactivity?

Radioactivity is the process of emitting or absorbing energy from a source and the total amount of energy emitted or absorbed is the only measure of radioactivity. If the energy is absorbed, it will be transformed into something. In this process, atoms or molecules emit radiation, which can be detected with a detector. The types of radiation emitted by radioactive elements can be classified into the following categories: alpha, beta, gamma and neutron radiation.

There are three types of radioactivity:

  1. Alpha decay
  2. Gamma decay
  3. Beta decay

Alpha decay: Alpha decay occurs when the nucleus of an atom spontaneously breaks down into two protons and two neutrons, the latter becoming part of a new nucleus with an atomic number 2 less than that of the original nucleus. Because the original nucleus contains more protons than neutrons, the new nucleus will contain more neutrons than protons.

Gamma decay: Gamma γ is the decay of some stable isotope of radioisotope, for example, the isotope of oxygen, hydrogen or nitrogen. The decay of the isotopes of the elements generates energy in the form of gamma rays (gamma rays). Gamma γ decay is the process by which the energy is converted into particles.

Beta decay: Beta decay is the spontaneous transformation of an atomic nucleus from a more stable form into a less stable form. Usually, the nucleus with greater mass than the one it decayed into will have a higher probability of being the one in the less stable form.

Laws of Radioactivity

  1. The process of radioactivity is the result of the decay of the nucleus, which is a natural process where the nucleus of an atom breaks down into smaller parts.
  2. The rate of radioactive decay of the nucleus is independent of the extent of the reaction and is not affected by temperature and pressure.
  3. Radioactivity is based on the law that states that a charge is never created or destroyed, or the law of conservation of charge.
  4. The chemical and physical properties of the daughter nucleus are dependent on which element the daughter nucleus is composed of and these properties differ from the properties of the mother nucleus.
  5. The energy which is emitted from radioactivity is always accompanied by the particles alpha, beta and gamma.
  6. The decay rate of radioactive substances is dependent upon the number of atoms at the time. It does not matter how long the atoms are there when the decay begins.

Units of Radioactivity

There are two units of radioactivity, Curie and Rutherford. There is a relationship between Curie and Rutherford: 1C = 3.7 × 104 Rd.

Uses of Radioactivity

  1. In the United States, to detect smoke in the house, an Americium-241 alpha emitter is used.
  2. The Americium sample releases the alpha particle in the chamber, which ionises the air and automatically leads to a small amount of current in the chamber.
  3. When smoke or other airborne radioactive materials enter the chamber, it will cause a drop in the current, causing the alarm to ring.
  4. Although Alpha particles’ range is very short, they destroy anything within reach of their impact.

Advantages and Disadvantages of Radioactivity

Advantages of Radioactivity

  1. For scanning the internal part of the body, gamma rays are used.
  2. For destroying carcinogenic cells, cobalt-60 is used.
  3. To kill the cancerous cells, gamma rays are used.
  4. For killing the microbes and increasing the shelf life of food, gamma rays are helpful.

Disadvantages of Radioactivity

  1. Isotopes for radioactivity are expensive
  2. The excessive dosage of radiation of radioactivity is harmful and even deadly.

Conclusion

The laws of radioactivity are complicated, but we can simplify them to the following: All charged particles that are emitted from radioactive sources must have an electron-with-positron pair in their centre. This pair has a negative charge and a positive charge. Because of the positive charge, the particle has lower energy than the pair and therefore, a greater chance of being emitted. The rarer the electron-positron pair, the more likely it is to be emitted. These laws state that radioisotopes are inherently dangerous because they are unstable and decay in the presence of oxygen. When a radioactive element decays, it releases energy in the form of gamma rays. These are powerful, penetrating beams of radiation that can be used to kill large numbers of humans.

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What are the health concerns in children that radioactivity causes?

Ans. Radioactivity is one of the most common causes of death for children. It is also the most prevalent cause of pr...Read full

What are the units of radioactivity?

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Is radioactivity dependent or independent of temperature and pressure?

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What is radioactivity?

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Explain radioactivity based on the law of conservation of charge.

Ans. Law of conservation of charge here means that radioactivity is based on the law that states that charge is neve...Read full