It is known as radioactivity (also called radioactivity , as accepted by the Royal Spanish Academy ) to the property of certain bodies endowed with atoms which, when disintegrating spontaneously, generate radiation . This physical phenomenon allows the printing of photographic plates, the generation of fluorescence or the ionization of gases, among other issues.
It should be noted that radiation can be classified as electromagnetic (X-rays or gamma rays) or corpuscular . When crossing a means, medium , the radioactivity ionizes it, either directly or indirectly.
An element has radioactivity when its isotopes they are not stable and need to lose Energy to reach its fundamental state. This loss of energy occurs with emissions of electromagnetic particle type, which allows you to modify the energy present in your nucleons or electrons, or vary the isotope.
The radioactivity we have to expose that has its origin in the nineteenth century and more specifically in the year 1896 because it was when the French physicist Henri Becquerel (winner of the Nobel Prize in Physics in 1903) discovered it by chance. And it is that he was working on the phenomena of phosphorescence and fluorescence with a mineral that contained uranium, the Pechblenda crystal.
Thus, from that and by the pure chance that one day of sunshine discovered that the photographic plate with which he operated, next to the aforementioned uranium, was veiled even though he had not received the rays of the Astro King, it was as he understood That said crystal possessed radiation.
This scientist was the pioneer but nonetheless it would be the great Polish physicist and chemist Marie Curie who would establish the term of radioactivity. Specifically, from the study of the aforementioned Becquerel, she and her husband developed numerous studies discovered, for example, the radioactivity of thorium.
But that was only the starting point because from there they continued working and found other chemical elements that also shared that quality. This would be the case with radio or polonium. An element of the latter that curiously received its name in honor of Marie's homeland.
The result of all this was not only the discovery of radioactivity but also the obtaining of this woman, along with her husband and Becquerel, from the Nobel Prize in Physics in 1903.
A distinction can be made between the natural radioactivity (the one manifested by isotopes found in nature) or artificial (induced by artificial alterations). It should be noted that the human being appeals to radioactivity to generate nuclear energy or to perform various diagnoses and therapies in the medicine .
Radioactivity, whose unit of measure in the International system is the becquerel , implies risks for Health human These risks, however, are very variable and depend on the intensity of the radiation, the duration of exposure and the type of tissue affected.
That is why it is considered that the radiation of natural origin that arises from the environment is not harmful, as long as they remain below a certain level. In order not to exceed this limit, the person must control the exposure time to the radiation source and have some type of shield.