Units of Radioactivity

Radioactivity is the state of the nucleus that is seeking stable configuration. It is the act of emitting radiation autonomously, as the term implies. An unstable atomic nucleus gives up some energy in order to shift to a more stable state. A nucleus has many neutrons that emit a negative beta particle, converting one of the neutrons to a proton. Similarly, a nucleus has many protons that emit a positively charged positron, converting a proton to a neutron. A nucleus with too much energy will generate a gamma-ray that does not affect any of the particles in the nucleus. A nucleus with heavy mass emits an alpha particle, discarding heavy particles like He nucleus.

Measurement of radioactivity

Being one of the physical phenomena, radioactivity can be determined by counting the number of atoms that decay autonomously each second. Instruments designed to detect the specific type of radiation released with each disintegration can be used to do this. The emission of particles from nuclei to gain the state of nuclear stability is termed radioactivity. Due to a large number of disintegrations per second, the Curie unit was used to measure the amount of radioactivity (Ci), named after Pierre and Marie Curie, the discoverers of radium. Originally, it was equal to one gram of radium-226 when counting the value of 1 curie = 3.7×1010 radioactive decay per second.

SI Unit of radioactivity

The current International System of Measurements (SI) unit for radioactivity is becquerel “Bq”, which is named after Henri Becquerel, who discovered radioactivity. It can be defined as the synonym for “1 disintegration per second”, or the activity of an amount of radioactive material in which the breakdown rate is one decay per second. The mathematical value for the same is defined as 1 becquerel = 1 radioactive decay per second = 2.703 × 10-11.

Radioactivity Decay

A nucleus may achieve stability in a single decay or decay through a sequence of stages before reaching a fully stable configuration. As the transfer to the next state is made, each stage will have its own respective half-life and unique type of radiation that will be emitted throughout. The knowledge of these degradation chains has come from a lot of scientific effort, which has led us to understand the nature of the materials and construct various nuclear weapons and reactors.

Half-Life

The half-life of a material is defined as the time taken for one-half of the atomic nuclei of a radioactive sample to decay . The radioactive half-life (t1/2) is one of the most useful measures for calculating how rapidly a nuclide will decay. The rate of disintegration is constant and independent of influencing factors such as time; as a result, the likelihood of it collapsing does not grow with time but remains constant. The decay constant is denoted by “λ”, mathematically expressed as Radioactive decay law: N = (N). (e)-λt.

Types of radioactive decay

Alpha decay 

A nucleus breaks up into two chunks during alpha decay. A pair of protons connected to a pair of neutrons (it is termed an alpha particle, which is a collection of particles that is effectively a helium nucleus), and the original nucleus minus the chunk.

Beta-decay

The neutrons in the nucleus turn into a proton during beta decay, which results in an increase in the element’s atomic number. The balance is carried out when the nucleus of the atom develops and discharges an electron against the positive charge it receives from converting a neutron to a proton. Free electrons then expel the “radiation” or the disintegration of the beta decay. The other particle that is discharged is called an antineutrino, claimed as a strange particle with no charge and negligible mass. 

Gamma decay

The type of radiation disintegration where the change in composition during gamma decay is constant. For example, if we begin with a nucleus that has 10 protons and 10 neutrons and ends with a nucleus that has 10 protons and 10 neutrons. The nucleus is a collection of protons and neutrons; the protons and neutrons can be arranged in various ways, resulting in these configurations having different lower total energy. The radiation may shift total energy from higher to lower configuration to a nucleus with protons that were initially close together.

Conclusion

Radioactivity is the process of emitting the material’s acquired energy to achieve stability. The energy emission is done through the activities of neutrons and protons, which change into one another to emit various energy rays. Radioactivity is termed as the disintegration or the decay of the substance per unit of time. The disintegration can be calculated with various measuring tools, which give out results in units like Curie, Rutherford, etc. The process of decay involves various types of decay named alpha, beta and gamma, which are hazardous. The SI unit is becquerel.