The Greek word katión He came to English as cation, which resulted in our language in cation The term is used with reference to a ion that has a positive charge .
To understand precisely what a cation is, therefore, we must analyze the notions that are mentioned in its definition. A cation is a ion class : a atom , or set of atoms, which obtains electric charge through the gain or loss of electrons .
Remember that atoms which are those particles that cannot be divided through a chemical process and that are composed of electrons (elementary particles that have a negative electrical charge) that surround a nucleus .
He ion that has an electric charge positive when adding or losing electrons, in short, it is a cation. When the cations establish a ionic bond with the anions (ions that have a negative electrical charge), form a Salt . These salts are usually the result of the chemical reaction that is generated between a base (which provides the cation) and a acid (which supplies the anion).
The Salt which is used to spice up food is an example of the product of these types of reactions that involve a cation and an anion. In this case, the base sodium hydroxide provides the cation by reacting with the hydrochloric acid , which adds the anion. The result is the product known as sodium chloride: the table salt .
It is important to mention that cations are found in the body of the human being through the potassium , he sodium and other elements that constitute ionized salts.
The science has documented the existence of a very large number of cations, each with its traditional name (or old), its symbol and its name IUPAC . This last acronym corresponds to the International Union of Pure and Applied Chemistry , whose original name in English is International Union of Pure and Applied Chemistry; It is a group formed by national societies dedicated to chemistry, with the power to develop standards for naming chemical compounds.
By looking at the list of the most frequent cations, we can make a distinction between the simple and the polyatomic ; In the first group are the following (according to the nomenclature that IUPAC has recognized): aluminum , barium, beryllium, calcium, chromium III, cobalt II, copper II, gallium, helium, hydrogen, lead, magnesium, lithium, manganese II, nickel II, potassium, silver, sodium, strontium, tin II and zinc.
Some of the most common polyatomic cations, meanwhile, are ammonium, hydronium, nitronium and mercury I; the only one of these that has a traditional name different from the one provided by the IUPAC is the last one, which is known as mercurious cation.
It is important to note that the nomenclature It is one of the fundamental points of science, since it allows to standardize the names of the various discoveries to facilitate their study and dissemination at international level, as well as over time. In the case of cations, IUPAC recommended in 2005 that all those who, according to their old or traditional nomenclature, had the termination "-ico" or "-oso" cease to be used, with the sole exception of oxoacids.
In the biology , the cations have various roles of great importance; for example, the transport of various organic molecules into cells is carried out by means of cell membranes whose electrochemical potentials are maintained by the concentration gradients of various cations. On the other hand, they promote the transmission of nerve impulses and the contraction of the muscles, and participate in catalytic functions since they are found in the active centers of many enzymes.