AND HE

(from the Greek ion - walking), electrically charging. particles formed during the loss or addition of electrons by atoms, molecules, radicals, etc. I. can accordingly be positive (with the loss of electrons) and negative (with the addition of electrons), I. is a multiple of the charge of the electron -on the. I. can be part of molecules and exist in an unbound state (in gases, liquids, plasma).

Physical encyclopedic dictionary. - M.: Soviet Encyclopedia. . 1983 .

ION (from the Greek ion - going) is an electrically charged particle formed by the separation or attachment of one or more. electrons (or other charged particles) to an atom, molecule, radical, or other ion. Positively charged I. are called. cations, negatively charged - anions, etc. I. denote chemical. a symbol with an index (top right) indicating the sign and magnitude of the charge - multiplicity I. - in units of electron charge (for example, Li +, H 2 +, SO 4 2-). Atomic I. also denote chemical. symbol of an element with Roman numerals indicating the multiplicity of I. (for example, NI, NII, NIII, which corresponds to N, N +, N 2+; in this case, Roman numerals are spectroscopic symbols Z , they are greater than the charge of the ion Z i by one: Z = Z i + l). Sequence of I. various chemicals. elements containing the same number of electrons form (see, for example, Hydrogen-like atoms). The concept and term "I." (as well as " " and "anion") were introduced in 1834 by M. Faraday. To remove an electron from a neutral atom or it is necessary to spend a certain amount. energy, so called ionization energy. The ionization energy per electron charge is called ionization potential. The characteristic opposite to the ionization energy - - is equal to the binding energy of the complement, the electron in the negative. I. Neutral atoms are ionized under the influence of optical quanta. radiation, x-ray and g-radiation, electric. fields during collisions with other atoms, electrons and other particles, etc. a DNA molecule carrying a negatively charged phosphate group PO 4 - in each of its repeating units. Some molecules found in solutions and crystals remain generally electrically neutral, although they contain decomposition. in its areas there are oppositely charged groups, they are called. zwitterions. Thus, the amino acid molecule H 2 N - CHP-COOH (P is a side radical) transforms into the zwitterionic form H 3 N-CHP-COO -, which is accompanied by the transfer of a proton from the COOH group to the H 2 N group. A complex consisting of several. neutral atoms or molecules and simple I. forms complex I., called. cluster ion. In gases, under normal conditions, the formed ions are short-lived, however, at high temperatures and pressures, the degree of ionization of the gas increases with increasing temperature and pressure, and at very high temperatures and pressures the gas turns into plasma. In liquids, depending on the nature of the solvent and solute, cations and anions can be located at an almost infinite distance from each other (in the case when they are surrounded by solvent molecules), but they can also be quite close to each other and, interacting strongly, form the so-called ion pairs. Solid salts usually form ionic crystals. The interaction energy of atomic particles as a function of the distance between them can be calculated using decomp. approximate methods (see Intermolecular interaction). The energy levels of atomic and molecular ionization and neutral particles are different and, in principle, can be calculated by the methods of quantum mechanics, as well as ionization energies. Optical The spectra of atomic energy are similar to the spectra of neutral atoms with the same number of electrons; they are only shifted to the short-wave range, since the lengths of the spectral lines corresponding to quantum transitions between energy levels with different values ​​of the ch. quantum number are proportional to the square of the nuclear charge. In the spectra of I. the so-called satellite lines, the analysis of which allows one to study the structure and properties multiply charged ions. The ion component has a significant impact on the parameters of laboratory and astrophysical plasmas. The study of energy is important for various fields of physics and plasma chemistry, astrophysics, quantum electronics, for studying the structure of substances, etc. Energy is widely used in experiments. research and instruments (mass spectrometers, Wilson chambers, ion projector, ion beams, etc.). Lit.: Smirnov B. M., Negative ions, M., 1978; Presnyakov L.P., Shevelko V.P., Yanev R.K., Elementary with the participation of multiply charged ions, M., 1986. V.G. Dashevsky.

Physical encyclopedia. In 5 volumes. - M.: Soviet Encyclopedia. Chief Editor A. M. Prokhorov. 1988 .

See what “ION” is in other dictionaries:

This term has other meanings, see Ion (meanings). “ION” Type Private company ... Wikipedia

and he- An atom or group of atoms that, through the loss or gain of one or more electrons, has acquired an electrical charge. If the ion is derived from a hydrogen atom or a metal atom, it is usually positively charged; if the ion is obtained from a non-metal atom... ... Technical Translator's Guide

And husband. Razg. to (see Jonah). Report: Ionovich, Ionovna; decomposition Ionych. Dictionary of personal names. Ion See Yvon. Day Angel. Guide to names and birthdays. 2010… Dictionary of personal names

- (Ion, Ιων). Son of Xuthus, ancestor of the Ionian tribe. (Source: “A Brief Dictionary of Mythology and Antiquities.” M. Korsh. Saint Petersburg, published by A. S. Suvorin, 1894.) ION (Ίων), in Greek mythology, the Athenian king, son of Creusa. Father I. most... Encyclopedia of Mythology

ION, yon husband. harmony, sense, meaning, suitability. He is awkward, there is no ion in him. The window was not cut through to the ion, so I sealed it. Dahl's Explanatory Dictionary. IN AND. Dahl. 1863 1866 … Dahl's Explanatory Dictionary

Exist., number of synonyms: 17 addend (1) amphion (2) anion (1) ... Synonym dictionary

An atom (or a group of atoms, a complex ion) that carries a positive (cation) or negative (anion) electrical charge and is an independent or relatively independent component (building unit) of a substance or... ... Geological encyclopedia

Ion, Ion, from Chios, ca. 490 approx. 421 BC e., Greek poet. He often visited Athens, although he did not settle there forever. He was on friendly terms with Timon and Themistocles, and also knew Aeschylus and Sophocles. He staged the first tragedy in 451. To us... ... Ancient writers

In Greek mythology, the grandson of Hellenes, son of Xuthus (or Apollo); ancestor of the Ionian tribe. Became king of Athens; his sons Hopleth, Heleont, Egikorei, Argad are eponyms of the four most ancient phyla of Attica... Big Encyclopedic Dictionary

- (Ain) (possibly ruins), a city and a plain located in the north. the source of the Jordan (1 Kings 15:20; 2 Kings 15:29). I. was conquered by Aram. (Sir.) by King Benhadad, and later by Tiglath-pileser III (bib. Feglath-pileser). In 1 Kings 15:20 the names of the places are listed in... ... Brockhaus Biblical Encyclopedia

Books

• Ion Creangă. Selected works. Childhood memories. Fairy tales. Stories, Ion Creangă. Bucharest, 1959. Publishing house on foreign languages. With illustrations. Publisher's binding. The condition is good. The classic of Romanian and Moldavian literature Ion Creangă (1837-1889) in his…

IONS IONS are electrically charged particles formed from an atom (molecule) as a result of the loss or gain of one or more electrons. Positively charged ions are called cations, negatively charged ions are called anions.

Modern encyclopedia. 2000 .

See what “IONS” are in other dictionaries:

IONS- (from the Greek ion walking, wandering), atoms or chemical. radicals that carry electrical charges. Story. As Faraday first established, the conduction of electric current in solutions is associated with the movement of material particles carrying... ... Great Medical Encyclopedia

ions- – electrically charged atoms or molecules. General chemistry: textbook / A. V. Zholnin Ions are electrically charged particles that arise when atoms, molecules and radicals lose or gain electrons. Dictionary of Analytical Chemistry... ... Chemical terms

Products of the decomposition of any body through electrolysis. Dictionary foreign words, included in the Russian language. Chudinov A.N., 1910 ... Dictionary of foreign words of the Russian language

- (from the Greek iōn going), charged particles formed from an atom (molecule) as a result of the loss or gain of one or more electrons. In solutions, positively charged ions are called cations, negatively charged ions ... ... encyclopedic Dictionary

An ion (Greek ιόν “going”) is an electrically charged particle (atom, molecule), usually formed as a result of the loss or gain of one or more electrons by atoms or molecules. The charge of an ion is a multiple of the charge of an electron. Concept and... ... Wikipedia

Ions- (from the Greek ion going) electrically charged particles formed by the loss or gain of electrons (or other charged particles) by atoms or groups of atoms (molecules, radicals, etc.). The concept and term ions were introduced in 1834... ... Encyclopedic Dictionary of Metallurgy

- (from the Greek going), monatomic or polyatomic particles carrying electricity. charge, e.g. H +, Li+, Al3+, NH4+, F, SO42. Positive I. are called cations (from the Greek kation, literally going down), negative anion and m (from the Greek anion, ... ... Chemical encyclopedia

- (from the Greek ión going) electrically charged particles formed by the loss or gain of electrons (or other charged particles) by atoms or groups of atoms. Such groups of atoms can be molecules, radicals or other... Great Soviet Encyclopedia

ions- physical particles that carry a positive or negative charge. Positively charged ions carry fewer electrons than expected, and negative ions carry more... Universal additional practical explanatory dictionary by I. Mostitsky

- (physical) According to the terminology introduced into the doctrine of electricity by the famous Faraday, a body that undergoes decomposition by the action of a galvanic current on it is called an electrolyte, decomposition in this way is electrolysis, and the products of decomposition are ions.... ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron

Books

• Hydrogen ions cure cancer. Ray of hope, Garbuzov Gennady Alekseevich. Gennady Alekseevich Garbuzov is a famous scientist from Sochi, biologist, longtime follower of Academician Bolotov, specialist in the field alternative treatment oncological diseases. Perennial...
• Hydrogen ions treat cancer Ray of hope, Garbuzov G.. Gennady Alekseevich Garbuzov is a famous scientist from Sochi, biologist, longtime follower of Academician Bolotov, specialist in the field of alternative treatment of oncological diseases. .…

The term "ion" was first coined in 1834 by Michael Faraday. After studying the effect of electric current on solutions of salts, alkalis and acids, he came to the conclusion that they contained particles with a certain charge. Faraday called cations ions that, in an electric field, moved towards the cathode, which has a negative charge. Anions are negatively charged non-elementary ionic particles that, in an electric field, move towards the plus - the anode.

This terminology is still used today, and particles are studied further, which allows us to consider a chemical reaction as a result of electrostatic interaction. Many reactions proceed according to this principle, which made it possible to understand their progress and select catalysts and inhibitors to accelerate their progress and inhibit synthesis. It also became known that many substances, especially in solutions, are always in the form of ions.

Nomenclature and classification of ions

Ions are charged atoms or a group of atoms that have lost or gained electrons during a chemical reaction. They make up the outer layers of the atom and can be lost due to the low gravitational pull of the nucleus. Then the result of electron detachment is a positive ion. Also, if an atom has a strong nuclear charge and a narrow electron shell, the nucleus is an acceptor of additional electrons. As a result, a negative ion particle is formed.

The ions themselves are not only atoms with an excess or insufficient electron shell. It could also be a group of atoms. In nature, most often there are group ions that are present in solutions, biological fluids of organisms, and in sea ​​water. There are a huge number of types of ions, the names of which are quite traditional. Cations are ionic particles that are positively charged, and negatively charged ions are anions. They are called differently depending on their composition. For example, sodium cation, cesium cation and others. Anions have a different name because they most often consist of many atoms: sulfate anion, orthophosphate anion, and others.

Mechanism of ion formation

Chemical elements in compounds are rarely electrically neutral. That is, they are almost never in the state of atoms. In the formation of a covalent bond, which is considered the most common, the atoms also have some charge, and the electron density shifts along the bonds within the molecule. However, the ion charge is not formed here, because the covalent bond energy is less than the ionization energy. Therefore, despite different electronegativity, some atoms cannot completely attract the electrons of the outer layer of others.

In ionic reactions, where the difference in electronegativity between atoms is large enough, one atom can take electrons from the outer layer from another atom. Then the created connection becomes strongly polarized and breaks. The energy expended on this, which creates a charge on the ion, is called ionization energy. It is different for each atom and is indicated in standard tables.

Ionization is possible only when an atom or group of atoms is capable of either donating electrons or accepting them. This is most often observed in solution and salt crystals. The crystal lattice also contains almost immobile charged particles, devoid of kinetic energy. And since there is no possibility of movement in the crystal, the reactions of ions most often occur in solutions.

Ions in physics and chemistry

Physicists and chemists actively study ions for several reasons. Firstly, these particles are present in all known states of matter. Secondly, the energy of electron removal from an atom can be measured in order to use it in practical activities. Thirdly, ions behave differently in crystals and solutions. And fourthly, ions allow the conduction of electric current, and the physicochemical properties of solutions change depending on the concentrations of the ions.

Ionic reactions in solution

The solutions and crystals themselves should be considered in more detail. In salt crystals there are separately located positive ions, for example, sodium cations and negative ions, chlorine anions. The structure of the crystal is amazing: due to the forces of electrostatic attraction and repulsion, the ions are oriented in a special way. In the case of sodium chloride, they form what is called a diamond crystal lattice. Here, each sodium cation is surrounded by 6 chloride anions. In turn, each chloride anion is surrounded by 6 chlorine anions. Because of this, simple table salt dissolves in both cold and hot water at almost the same speed.

There is also no single molecule of sodium chloride in solution. Each of the ions here is surrounded by water dipoles and moves chaotically in its thickness. The presence of charges and electrostatic interactions leads to the fact that saline solutions of water freeze at a temperature just below zero, and boil at a temperature above 100 degrees. Moreover, if there are other substances in the solution that can enter into a chemical bond, then the reaction occurs not with the participation of molecules, but of ions. This created the doctrine of the stages of chemical reactions.

Those products that are obtained at the end are not formed immediately during the interaction, but are gradually synthesized from intermediate products. The study of ions made it possible to understand that the reaction proceeds precisely according to the principles of electrostatic interactions. Their result is the synthesis of ions that electrostatically interact with other ions, creating the final equilibrium reaction product.

Summary

A particle such as an ion is an electrically charged atom or group of atoms that is formed by the loss or gain of electrons. The simplest ion is the hydrogen one: if it loses one electron, it is only a nucleus with a charge of +1. It causes an acidic environment in solutions and environments, which is important for the functioning of biological systems and organisms.

Ions can have both positive and negative charges. Due to this, in solutions, each particle enters into electrostatic interaction with water dipoles, which also creates conditions for life and signal transmission by cells. Moreover, ion technology is being developed further. For example, ion engines have been created that have already equipped 7 NASA space missions.

And he- a monatomic or polyatomic electrically charged particle of a substance, formed as a result of the loss or gain by an atom in the molecule of one or more electrons.

The charge of an ion is a multiple of the charge of an electron. The concept and term “ion” was introduced in 1834 by Michael Faraday, who, while studying the effect of electric current on aqueous solutions of acids, alkalis and salts, suggested that the electrical conductivity of such solutions is due to the movement of ions. Faraday called positively charged ions moving in solution towards the negative pole (cathode) cations, and negatively charged ones moving towards the positive pole (anode) - anions.

The properties of ions are determined:

1) the sign and magnitude of their charge;
2) the structure of ions, i.e., the arrangement of electrons and the strength of their bonds, with outer electrons being especially important;
3) their sizes, determined by the radius of the outer electron’s orbit.
4) strength of the electronic shell (deformability of ions).

In the form of independent particles, ions are found in all aggregate states of matter: in gases (in particular, in the atmosphere), in liquids (in melts and solutions), in crystals and in plasma (in particular, in interstellar space).

Being chemically active particles, ions react with atoms, molecules and with each other. In solutions, ions are formed as a result of electrolytic dissociation and determine the properties of electrolytes.

Number of elementary electric charges for ions in solutions almost always coincides with the valence of a given atom or group; gas ions can have a different number of elementary charges. Under the influence of sufficiently energetic influences ( heat, high-frequency radiation, high-speed electrons) positive ions with different numbers of electrons, up to bare nuclei, can be formed. Positive ions are indicated by a + (plus) sign or a dot (for example, Mg***,Al +++), negative sign- (minus) or sign "(Сl - , Br"). The number of signs indicates the number of excess elementary charges. Most often, ions are formed with stable outer electron shells corresponding to the shell of noble gases. The ions from which crystals are built, and the ions found in solutions and solvents with high dielectric constants, mostly belong to this type, for example, alkali and alkaline earth metals, halogens, etc. However, there are also so-called. transition ions, in which the outer shells contain from 9 to 17 electrons; these ions can transform relatively easily into ions of a different type and significance (for example, Fe - -, Cu, etc.).

Chemical and physical properties

Chemical and physical properties ions differ sharply from the properties of neutral atoms, resembling in many respects the properties of atoms of other elements that have the same number of electrons and the same outer electron shell (for example, K" resembles Ar, F" - Ne). Simple ions, as shown by wave mechanics, have a spherical shape. The sizes of ions are characterized by the magnitude of their radii, which can be determined empirically from X-ray analysis of crystals (Goldschmidt) or calculated theoretically by wave mechanics (Paulig) or statistics (Fermi). The results obtained by both methods give quite satisfactory agreement. A number of properties of crystals and solutions are determined by the radii of the ions of which they are composed; in crystals, these properties are the energy of the crystal lattice and, to a large extent, its type; in solutions, ions polarize and attract solvent molecules, forming shells of variable composition; this polarization and the strength of the bond between ions and solvent molecules are determined almost exclusively by the radii and charges of the ions. How strong the effect of the ion field on solvent molecules is in general is shown by calculations by Zwicky, who found that water molecules are near the ions under a pressure of about 50,000 atm. The strength (deformability) of the outer electron shell depends on the degree of connectivity of the outer electrons and determines mainly the optical properties of the ions (color, refraction). However, the color of ions is also associated with the formation of ions of various compounds with solvent molecules. Theoretical calculations of effects associated with deformation electron shells, are more difficult and less rewarding than calculating the interaction forces between ions. The reasons for the formation of ions in solutions are not precisely known; the most plausible opinion is that the molecules of soluble substances are broken into ions by the molecular zero of the solvent; heteropolar, i.e. crystals built from ions, apparently give ions immediately when dissolved. The significance of the molecular field of the solvent is confirmed by the parallelism between the dielectric constant of the solvent, which is an approximate measure of the voltage of its molecular field, and the degree of dissociation (the Nernst-Thomson rule, experimentally confirmed by Walden). However, ionization also occurs in substances with low dielectric constants, but here electrolytes, which produce complex ions, dissolve predominantly. Complexes are sometimes formed from ions of the soluble substance; sometimes the solvent also takes part in their formation. Substances with low dielectric constants are also characterized by the formation of complex ions when non-electrolytes are added, for example (C 2 H 5)0Br 3 gives a conductive compound when mixed with chloroform
system. An external sign of the formation of complex ions is the so-called. anomalous electrical conductivity, in which a graph depicting the dependence of molar electrical conductivity on dilution gives a maximum in the region of concentrated solutions and a minimum with further dilution.

Nomenclature According to chemical nomenclature, the name of a cation consisting of one atom coincides with the name of the element, for example, Na + is called sodium ion, sometimes a charge is added in parentheses, for example, the name of the Fe 2+ cation is iron (II) ion. The name consists of one atom of the anion and is formed from the root of the Latin name of the element and the suffix " -id/-id", for example, F - is called a fluoride ion.