Examples of isotopes in chemistry are considered on hydrogen. This term refers to varieties of one chemical element that have the same atomic (ordinal) number, but different mass numbers. In the periodic system of Dmitry Ivanovich Mendeleev, there are many chemical elements, and quite a lot of those that have isotopes that differ in mass number.
Important information
An example of hydrogen isotopes indicates that with a different number of neutrons, protium, deuterium, tritium have completely different chemical properties.
Most often, an isotope is denoted by the symbol of the element to which it belongs, adding an upper left index that determines the mass number. It is also allowed to write its name with the addition of a hyphen of the mass number. For example, you can see the following options: radon-222, carbon-12.
Considering examples of isotopes in chemistry, we note that some have their own names: tritium,deuterium, protium.
Features of terminology
The term was first proposed in the plural, as it was used to compare two types of atoms. Its use in the singular has come into practice. Currently, examples of isotope use are uniform in use from the point of view of international scientific organizations.
Discovery history
When analyzing examples of isotopes, it is necessary to dwell on some historical facts. The first evidence that substances that have the same chemical behavior have different physical properties was established as part of a study of radioactive transformations of atoms of heavy elements.
At the beginning of the nineteenth century, it was found that the product of the radioactive decay of the uranium atom is ionium, and radiothorium is formed from thorium, which have similar chemical properties, but differ significantly in atomic mass and characteristics of radioactive decay.
A little later it was found that these products have the same X-ray and optical spectra. Substances that are similar in chemical properties, differing in the mass of atoms and some physical parameters, began to be called isotopes (suggested in 1910 by Soddy).
An example of isotopes can be seen on the hydrogen atom. Having a similar atomic mass, they differ in the number of neutrons.
By 2016, 3211 isotopes of various chemicalelements, and about 13% of their total number are stable or near-stable, and 40 percent are proton-excessive, that is, they deviate towards neutrons (protons).
It is interesting that the US, Germany, Great Britain, Russia, France are the leaders in discoveries in this area. An example of hydrogen isotopes is de alt with as part of the school curriculum in chemistry. The guys analyze the basic concepts: mass number, neutrons, charge number, characterizing protium, deuterium, tritium. Thanks to the discovery of the radioactive theory, it was possible to explain the main differences in the structure and properties of isotopes, to understand the possibilities of their application in various branches of chemistry.
