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Radioactivity-Alpha Decay

Radioactivity processes are very sudden, and energy liberated processes in nature. Alpha decay is one of its kind. This article will help you understand the concepts related to alpha decay.

Radioactivity is a phenomenon through which energy is produced from the spontaneous reactions of less stable nuclei. They have the characteristics such as the liberation of excess amounts of energy and spontaneous, first-order reactions. Alpha particles are positively charged atoms that carry two protons and two neutrons from the nucleus of an atom. Generally, they are ejected from radioactive elements, like Uranium, Radium, and Polonium. The Alpha decaying process is a nuclear decaying procedure in which the nucleus emits the alpha particle. Radioactive processes are very harmful and bring hazardous effects to the environment and living beings. This article will help you understand alpha particles.

Radioactivity: It is a phenomenon in which stable atomic nuclei are formed by a spontaneous disintegration of least or less stable atomic nuclei.

Features of radioactivity reactions

  •     Release of a tremendous amount of energy (exoergic).
  •     Random in nature (follows spontaneity).
  •     A kind of first-order process.
  •     Utilisation of a small amount of mass for producing energy.

Every radioactive species is characterised by its half-life because radioactive reactions come under first-order reactions. In the process of radioactive decay, an excess amount of energy is produced, generally ten lakh times more than the amount of energy produced during an exothermic reaction. This process is not affected by any parameters such as temperature and pressure, as it is a nuclear reaction instead of an electronic phenomenon. However, this can also be slightly altered by increasing the pressures on some radionuclides. Radioactive (unstable element) is shown by the chemical symbol of the element.

 

The S.I. a unit of radioactivity is Curie, named after Marie Curie, and it is defined as the 37 billion integration per second (dis/sec) i.e., 3.700 × 1010 disintegrations per second. Recently, a new unit is also used to measure the radioactive reaction is the Becquerel (1bq=1dis/sec).

Subunits of Curie are Pico Curie, microCurie, nano Curie, and milli Curie and its larger units are Kilo Curie and Mega Curie. Generally, PicoCurie to nano Curie is used to measure very low energy work levels. microCurie is used in usual energy work, like nuclear activation analysis studies and radiotracers. Radioactive related reactions are very harmful to the environment and living beings; hence special precautions must be taken to avoid mishaps.

The causes for the radioactivity are as follows;

  •     Natural causes
  •     Atomic bomb explosion
  •   Fusion and fission-related reactions from atomic reactor operations.

Alpha particles and alpha decaying process

Alpha particles: They are positively charged, carrying two protons and two neutrons from the nucleus of the atom. Mostly, the nucleus of the atom, they are made up of heavier radioactive elements, like Uranium, Radium, and Polonium. They consist of a very high amount of energy but over a small distance.

Alpha decay processes: It is a type of radioactive reaction in which an alpha particle is ejected from the non-stable atomic nuclei by spontaneous reactions leading to the liberation of excess amounts of energy. Since alpha particles consist of two positive charges and a combination of four units’ mass, they produce daughter nuclei having a positive nuclear charge or atomic number lesser than the parental atomic nuclei. For instance, Polonium – 210, (atomic number=84, mass number=210) decays in alpha reactions and produces 206 (atomic number =82).

In other words, the alpha decay process is a nuclear decaying procedure in which the nucleus emits the alpha particle. During the alpha decay, an energetically forbidden region formed, also called a potential barrier, from the distance out of the radius to the external sides of the atom.

The speed and energy of the ejected alpha particle are the critical properties of the parent nucleus and explain more features such as distance covered by alpha particles. Though the speed of ejected alpha particles is very less compared to light, they cover only a few centimetres. The emission of helium ions shows the sharp line of spectra when spectroscopic measurements are made. 

Harmful effects of alpha radiation

  •     Its harmful effects depend upon the exposure timing.
  •     Alpha particles penetrate the upper layer of the skin and damage the tissues.
  •     They damage the cells and DNA.

Conclusion

During radioactive reactions, random disintegration of unstable atomic nuclei takes place, which has the characteristics such as the liberation of excess amounts of energy, and spontaneous in nature, first-order reactions. Alpha particles are positively charged atoms that carry two protons and two neutrons from the nucleus of the atom. Generally, they are made up of heavier radioactive elements, like Uranium, Radium, and Polonium. The Alpha decaying process is a nuclear decaying procedure in which the nucleus emits the alpha particle. During the alpha decay, an energetically forbidden region formed, also called a potential barrier, from the distance out of the radius to the external sides of the atom.