All definitions are in inorganic chemistry. What is Inorganic Chemistry? Basic inorganic chemistry

"Concepts change, words remain." How true! How often one hears: "Turn on the electricity", "Turn off the electricity", although the speaker knows perfectly well that an electric light bulb is not turned on or extinguished, but included in the current circuit and turned off from it.

The words that survived the concepts that were previously invested in them include the designations of two departments of chemistry, traditionally called inorganic and organic chemistry.

For a long time, chemists, not being able to make most of those complex chemical compounds that are part of the organs of plants and animals, explained their inability by the fact that these substances are formed in plants and animals under the influence of a special "vital force" and cannot be synthesized in flasks and retorts.

The famous German chemist Weller adhered to the same view. personal experience I happened to be convinced of the fallacy of this view. From undoubtedly inorganic compounds of nitrogen and carbon with oxygen, he obtained a complex substance, which turned out to be a typical "organic" compound known earlier - urea.

Now we firmly know that no "life force" is needed to obtain any substance that is part of plants and animals, that they can all be built from their constituent elements. The fact that not all of them have been artificially obtained yet does not bother us in the least. Not received at modern means synthesis - will be obtained when these tools are improved.

In reality, all the so-called "organic" compounds are carbon compounds. Unlike other elements, carbon is capable of producing many tens of thousands of compounds with other simple substances. Exclusively for the convenience of study, all the diverse compounds of carbon are reduced to a discipline separate from the chemistry of other elements, "from old memory" called organic chemistry.

The most important curiosity is that now in the courses of "organic" chemistry a huge number of such carbon compounds are being studied, which cannot be found in any plant or animal.

The beginning of this synthetic construction of "organic" substances that do not exist in nature, created by a chemist in his flasks, retorts and factory apparatus, was laid by the accidental discovery of an 18-year-old student, Perkins.

Perkins decided to make a synthetic medicinal substance quinine, extracted from the bark of the cinchona tree. Having received in the course of his research some new compound, he wanted to study its solubility and, dissolving in alcohol, he saw that the solution had a magnificent purple color.

"Couldn't it be used as paint?" thought Perkins. It turned out that it is very possible that the solution perfectly dyes wool and silk in a beautiful lilac color.

Perkins gave up on science, dropped out of university and founded the world's first factory of artificial "organic" paints. Following him, hundreds of other chemists began to synthesize more and more new carbon compounds, which have found application not only as paints, but also as disinfectants, anesthetics (pain relievers), medicinal, poisonous and explosive substances.

Subject and tasks of chemistry

Modern chemistry is one of the natural sciences and is a system of separate disciplines: general and inorganic chemistry, analytical chemistry, organic chemistry, physical and colloidal chemistry, geochemistry, cosmochemistry, etc.

Chemistry is a science that studies the processes of transformation of substances, accompanied by changes in composition and structure, as well as mutual transitions between these processes and other forms of motion of matter.

Thus, the main object of chemistry as a science is substances and their transformations.

At the present stage of development of our society, taking care of human health is a task of paramount importance. The treatment of many diseases has become possible thanks to the achievements of chemistry in the field of creating new substances and materials: drugs, blood substitutes, polymers and polymeric materials.

Not having deep and versatile knowledge in the field of chemistry, not understanding the meaning of positive or negative influence various chemical factors on human health and the environment, one cannot become a competent medical worker.

General chemistry. Inorganic chemistry.

Inorganic chemistry is the science of the elements of the periodic system and the simple and complex substances formed by them.

Inorganic chemistry is inseparable from general chemistry. Historically, in the study of the chemical interaction of elements with each other, the basic laws of chemistry, the general laws of the course of chemical reactions, the theory chemical bond, the doctrine of solutions and much more, which is the subject of general chemistry.

Thus, general chemistry explores the theoretical concepts and concepts that form the foundation of the entire system chemical knowledge.

Inorganic chemistry has long stepped over the stage of descriptive science and is currently experiencing its "rebirth" as a result of the widespread involvement of quantum chemical methods, the band model energy spectrum electrons, the discovery of valence-chemical compounds of noble gases, the targeted synthesis of materials with special physical and chemical properties. Based on a deep study of the relationship between chemical structure and properties, it successfully solves the main problem - the creation of new inorganic substances with desired properties.

2. Methods of general and inorganic chemistry.

Of the experimental methods of chemistry, the most important is the method of chemical reactions. Chemical reaction - the transformation of some substances into others by changing the composition and chemical structure... Chemical reactions make it possible to investigate the chemical properties of substances. By the chemical reactions of the investigated substance, one can indirectly judge its chemical structure. Direct methods of establishing the chemical structure are mostly based on the use of physical phenomena.

Also, on the basis of chemical reactions, inorganic synthesis is carried out, which has recently achieved great success, especially in the preparation of highly pure compounds in the form of single crystals. This was facilitated by the use of high temperatures and pressures, high vacuum, the introduction of containerless cleaning methods, etc.

When carrying out chemical reactions, as well as when isolating substances from a mixture in pure form, preparative methods play an important role: precipitation, crystallization, filtration, sublimation, distillation, etc. Nowadays, many of these classic preparative methods have received further development and are leading in the technology of obtaining especially pure substances and single crystals. These are methods of directional crystallization, zone recrystallization, vacuum sublimation, fractional distillation. One of the features of modern inorganic chemistry is the synthesis and study of highly pure substances on single crystals.

The methods of physicochemical analysis are widely used in the study of solutions and alloys, when the compounds formed in them are difficult or practically impossible to isolate in an individual state. Then investigate physical properties systems depending on changes in composition. As a result, a composition-properties diagram is built, the analysis of which allows one to draw a conclusion about the nature of the chemical interaction of the components, the formation of compounds and their properties.

To understand the essence of the phenomenon, experimental methods alone are not enough, therefore Lomonosov said that a true chemist must be a theoretician. Only through thinking, scientific abstraction and generalization are the laws of nature cognized, hypotheses and theories are created.

The theoretical understanding of the experimental material and the creation of a coherent system of chemical knowledge in modern general and inorganic chemistry is based on: 1) the quantum-mechanical theory of the structure of atoms and the periodic table of elements of D.I. Mendeleev; 2) quantum-chemical theory of chemical structure and the doctrine of the dependence of the properties of a substance on “its chemical structure; 3) the doctrine of chemical equilibrium based on the concepts of chemical thermodynamics.

3. Fundamental theories and laws of chemistry.

The fundamental generalizations of chemistry and natural science include atomic-molecular theory, the law of conservation of mass and energy,

Periodic table and the theory of chemical structure.

a) Atomic-molecular theory.

The creator of atomic-molecular studies and the discoverer of the law of conservation of mass of substances M.V. Lomonosov is rightfully considered the founder of scientific chemistry. Lomonosov clearly distinguished two stages in the structure of matter: elements (in our understanding, atoms) and corpuscles (molecules). According to Lomonosov, the molecules of simple substances are made up of the same atoms, and the molecules of complex substances are made up of different atoms. The atomic-molecular theory received universal recognition in early XIX centuries after the approval of Dalton's atomism in chemistry. Since then, molecules have become the main object of research in chemistry.

b) The law of conservation of mass and energy.

In 1760 Lomonosov formulated a unified law of mass and energy. But before the beginning of the XX century. these laws were considered independently of each other. Chemistry mainly dealt with the law of conservation of the mass of matter (the mass of substances that entered into a chemical reaction is equal to the mass of substances formed as a result of the reaction).

For example: 2КСlO 3 = 2 КСl + 3O 2

Left: 2 potassium atoms Right: 2 potassium atoms

2 chlorine atoms 2 chlorine atoms

6 oxygen atoms 6 oxygen atoms

Physics dealt with the law of conservation of energy. In 1905 the founder modern physics A. Einstein showed that there is a relationship between mass and energy, expressed by the equation E = mc 2, where E is energy, m is mass; c is the speed of light in vacuum.

c) Periodic law.

The most important task of inorganic chemistry is to study the properties of elements, to identify the general laws of their chemical interaction with each other. The largest scientific generalization in solving this problem was made by D.I. Mendeleev, who discovered the Periodic Law and its graphic expression - the Periodic Table. It was only as a result of this discovery that chemical prediction, the prediction of new facts, became possible. Therefore, Mendeleev is the founder of modern chemistry.

Mendeleev's periodic law is the basis of natural
taxonomists chemical elements... Chemical element - aggregate
atoms with the same nuclear charge. Regularities of changing properties
chemical elements are determined by the Periodic Law. Teaching about
structure of atoms explained physical meaning Periodic Law.
It turned out that the frequency of changes in the properties of elements and their compounds
depends on the periodically repeating similar structure of the electronic
shells of their atoms. Chemical and some physical properties depend on
the structure of the electron shell, especially its outer layers. That's why
The periodic law is the scientific basis for studying the most important properties of elements and their compounds: acid-base, redox, catalytic, complex-forming, semiconductor, metal-chemical, crystal-chemical, radiochemical, etc.

The periodic table also played a colossal role in the study of natural and artificial radioactivity, the release of intranuclear energy.

The Periodic Law and the Periodic Table are constantly evolving and refining. The proof of this is the modern formulation of the Periodic Law: the properties of elements, as well as the forms and properties of their compounds, are periodically dependent on the magnitude of the charge of the nucleus of their atoms. Thus, the positive charge of the nucleus, and not the atomic mass, turned out to be a more accurate argument on which the properties of elements and their compounds depend.

d) Theory of chemical structure.

The fundamental task of chemistry is to study the relationship between the chemical structure of a substance and its properties. The properties of a substance are a function of its chemical structure. Before A.M. Butlerov believed that the properties of a substance are determined by its qualitative and quantitative composition. He was the first to formulate the basic proposition of his theory of chemical structure. Thus: the chemical nature of a complex particle is determined by the nature of the elementary constituent particles, their number and chemical structure. Translated into modern language this means that the properties of a molecule are determined by the nature of its constituent atoms, their number and the chemical structure of the molecule. Initially, the theory of chemical structure referred to chemical compounds with a molecular structure. At present, the theory created by Butlerov is considered a general chemical theory of the structure of chemical compounds and the dependence of their properties on the chemical structure. This theory is a continuation and development of Lomonosov's atomic-molecular teachings.

4. The role of domestic and foreign scientists in the development of general and

inorganic chemistry.

Inorganic chemistry- a section of chemistry, which is associated with the study of the structure, reactivity and properties of all chemical elements and their inorganic compounds. This area of ​​chemistry encompasses all compounds, with the exception of organic substances (the class of compounds that include carbon, with the exception of a few simpler compounds, usually inorganic). Differences between organic and inorganic compounds, containing, are arbitrary according to some representations. Inorganic chemistry studies chemical elements and the simple and complex substances(except organic). The number of inorganic substances known today is approaching 500 thousand.

The theoretical foundation of inorganic chemistry is periodic law and based on it periodic system of D. I. Mendeleev... The main task of inorganic chemistry is the development and scientific substantiation of methods for creating new materials with the necessary modern technology properties.

Classification of chemical elements

Periodic table of chemical elements ( Mendeleev table) - classification of chemical elements, which establishes the dependence of various properties of chemical elements on the charge of the atomic nucleus. The system is a graphic expression of the periodic law,. Its initial version was developed by D. I. Mendeleev in 1869-1871 and was called "Natural system of elements", which established the dependence of the properties of chemical elements on their atomic mass... In total, several hundred variants of the image of the periodic system have been proposed, but in the modern version of the system, it is assumed that the elements are reduced to a two-dimensional table, in which each column (group) determines the basic physicochemical properties, and the lines represent periods that are somewhat similar to each other.

Simple substances

They consist of atoms of one chemical element (they are a form of its existence in a free state). Depending on what is the chemical bond between atoms, all simple substances in inorganic chemistry are divided into two main groups: and. The former are characterized by a metallic bond, while the latter are characterized by a covalent bond. Also, there are two groups adjacent to them - metal-like and non-metal-like substances. There is such a phenomenon as allotropy, which consists in the possibility of the formation of several types of simple substances from atoms of the same element, but with a different structure of the crystal lattice; each of these types is called allotropic modification.

Metals

(from Latin metallum - mine, mine) - a group of elements with characteristic metallic properties, such as high thermal and electrical conductivity, positive temperature coefficient of resistance, high plasticity and metallic luster. Of the 118 chemical elements discovered at the moment, metals include:

• 38 in the group of transition metals,
• 11 in the group of light metals,
• 7 in the group of semi-metals,
• 14 in the group lanthanides + lanthanum,
• 14 in the group actinides + anemones,
• outside of certain groups.

Thus, 96 of all discovered elements belong to metals.

Nonmetals

Chemical elements with typically non-metallic properties, occupying the upper right corner of the Periodic Table of the Elements. In molecular form, in the form of simple substances in nature, there are

Inorganic chemistry.

Inorganic chemistry is a branch of chemistry that studies the properties of various chemical elements and the compounds they form, with the exception of hydrocarbons (chemical compounds of carbon and hydrogen) and their substitution products, which are so-called organic molecules.

The first studies in the field of inorganic chemistry were devoted to minerals. The goal was to extract various chemical elements from them. These studies made it possible to divide all substances into two large categories: chemical elements and compounds.

Chemical elements are substances consisting of identical atoms (for example, Fe, of which an iron rod is made, or Pb, of which a lead pipe is made).

Chemical compounds are substances composed of different atoms... For example, water Н20, sodium sulfate Na2S04, ammonium hydroxide NH4OH ...

The atoms that make up chemical elements and compounds are divided into two classes - metal atoms and non-metal atoms.

Nonmetal atoms (nitrogen N, oxygen O, sulfur S, chlorine CI.) Have the ability to attach electrons to themselves, taking them away from other atoms. Therefore, atoms of non-metals are called "electronegative".

In contrast, metal atoms tend to donate electrons to other atoms. Therefore, metal atoms are called electropositive. These are, for example, iron Fe, lead Pb, copper Cu, zinc Zn. Substances consisting of two different chemical elements usually contain metal atoms of the same type (the designation of the corresponding atoll is placed at the beginning of the chemical formula) and non-metal atoms of the same type (in the chemical formula, the designation of the corresponding atom is placed after the metal atom). For example, sodium chloride NaCl. If the substance does not contain a metal atom, then the least electronegative element, for example, ammonia NH3, is placed at the beginning of the chemical formula.

The naming system for inorganic chemical compounds was approved in 1960 The International Union IUPAC. Inorganic chemical compounds called, first pronouncing the name of the most electronegative element (usually a non-metal). For example, connecting with chemical formula KCI is called potassium chloride. The substance H2S is called hydrogen sulfide, and CaO is called calcium oxide.

Organic chemistry.

At the beginning of its development, this chemistry investigated substances that are part of living organisms - plants and animals (proteins, fats, sugars), or substances of decomposed living matter (oil). All these substances were called organic.

Naturally occurring organic matter belong to different groups: oil and its components, proteins, carbohydrates, fats, hormones, vitamins and others.

In the early 19th century, the first artificial organic molecules were synthesized. Using the inorganic salt of ammonium cyanate, Wöhler obtained urea in 1828. Acetic acid was synthesized by Kolbe in 1845. Berthelot obtained ethyl alcohol and formic acid (1862).

Over time, chemists have learned to synthesize more and more natural organic substances. Glycerin, vanillin, caffeine, nicotine, cholesterol were obtained.

Many of the synthesized organic substances do not exist in nature. These are plastics, detergents, artificial fibers, numerous medicines, dyes, insecticides.

Carbon forms more compounds than any other element. With a stable outer electron shell, carbon has very little tendency to become a positively or negatively charged ion. This electron shell arises from the formation of four bonds directed towards the vertices of the tetrahedron, in the center of which is the nucleus of the carbon atom. That is why organic molecules have a specific structure.

In organic molecules, the carbon atom is always involved in four chemical bonds. Carbon atoms are able to easily combine with each other to form long chains or cyclic structures.

Carbon atoms in organic molecules can be connected by single bonds (the so-called saturated hydrocarbons) or multiple, more precisely double, as well as triple bonds (unsaturated hydrocarbons).

The International Union IUPAC has developed a naming system for organic compounds. This system reveals the longest unbranched carbon chain, the type of chemical bond between carbon atoms, and the presence of various groups of atoms (substituents) attached to the main carbon chain.

The groups of carbon atoms give the organic molecules in which they are contained specific properties. The latter make it possible to distinguish between numerous classes of organic compounds, for example: hydrocarbons (substances from carbon and hydrogen atoms), alcohols, organic acids.

At this stage of evolution, not a single person can imagine his life without chemistry. After all, every day all over the world there are different chemical reactions, without which the existence of all living things is simply impossible. In general, there are two sections in chemistry: inorganic and organic chemistry. To understand their main differences, you first need to understand what these sections are.

Inorganic chemistry

It is known that this area of ​​chemistry studies all physical and chemical properties of inorganic substances, as well as their compounds, while taking into account their composition, structure, as well as the ability to various reactions with the use of reagents and in their absence.

They are both simple and complex. With the help of inorganic substances, new technically important materials are created that are in demand among the population. To be precise, this section of chemistry deals with the study of those elements and compounds that are not created by living nature and are not biological material, but are obtained by synthesis from other substances.

In the course of some experiments, it turned out that living things are capable of producing many inorganic substances, and there is also the possibility of synthesizing organic substances in the laboratory. But, despite this, nevertheless, it is simply necessary to separate these two areas, since there are some differences in the mechanisms of the passage of reactions, the structure and properties of the substances of these areas, which do not allow to combine everything into one section.

Allocate simple and complex inorganic substances ... Simple substances include two groups of compounds - these are metals and non-metals. Metals are elements that have all metallic properties, and there is also a metallic bond between them. This group includes the following types of elements: alkali metals, alkaline earth, transition, light, semimetals, lanthanides, actinides, as well as magnesium and beryllium. Of all the officially recognized elements of the periodic table, ninety-six elements out of one hundred and eighty-one possible, that is, more than half, are classified as metals.

The most famous of the non-metallic groups are oxygen, silicon, and hydrogen, while those less common are arsenic, selenium, and iodine. Simple non-metals also include helium and hydrogen.

Complex inorganic substances are divided into four groups:

• Oxides.
• Hydroxides.
• Salt.
• Acids.

Organic chemistry

This area of ​​chemistry examines substances that consist of carbon and other elements, those that come into contact with it, that is, create the so-called organic compounds. These can be substances of an inorganic nature, since a hydrocarbon can attach to itself many different chemical elements.

Most often, organic chemistry deals with synthesis and processing of substances and their compounds from raw materials of plant, animal or microbiological origin, although, especially recently, this science has grown far beyond the designated framework.

The main classes of organic compounds include: hydrocarbons, alcohols, phenols, halogen-containing compounds, ethers and esters, aldehydes, ketones, quinones, nitrogen-containing and sulfur-containing compounds, carboxylic acids, heterocyclic, organometallic compounds and polymers.

Substances studied by organic chemistry are very diverse, since, due to the presence of a hydrocarbon in their composition, they can bind with many other various elements... Of course, organic substances are also included in living organisms in the form of fats, proteins and carbohydrates, which perform various vital functions. The most important ones are energy, regulatory, structural, protective and others. They are part of every cell, every tissue and organ of every living being. Without them, the normal functioning of the body as a whole is impossible, nervous system, reproductive and others. This means that all organic substances play a huge role in the existence of all life on earth.

The main differences between them

In principle, these two sections are related to each other, but also have some differences. First of all, the composition of organic substances necessarily includes carbon, in contrast to inorganic, in which it may not be included. There are also differences in structure, in the ability to respond to various reagents and conditions created, in structure, in basic physical and chemical properties, in origin, in molecular weight etc.

In organic matter the molecular structure is much more complex than inorganic. The latter can melt only at sufficiently high temperatures and are extremely difficult to decompose, in contrast to organic ones, which have a relatively low melting point. Organic substances have a fairly bulky molecular weight.

Another important difference is that only organic substances have the ability form compounds with the same set of molecules and atoms, but which have different layout options. Thus, completely different substances are obtained, differing from each other in physical and chemical properties... That is, organic substances are prone to such a property as isomerism.