ChemistryTopics

Law of conservation of mass – total mass does not change during a chemical reaction; the total mass of the reactants equals the total mass of the products. law of constancy of composition – every pure chemical compound always keeps its constituent elements in a constant mass ratio. law of multiple proportions – when two elements form multiple compounds with each other, the masses of the other element per constant mass of one of the elements are in a simple integer ratio. law of volume proportions – the volumes of reacting and formed gases at the same temperature and pressure are in simple whole number ratios. avogadro's law – different gases have the same number of molecules in equal volumes at the same temperature and pressure.

An atom is the smallest particle that contains all the properties of a chemical element. an atom consists of a nucleus and electrons moving around it. the nucleus contains positively charged protons and uncharged neutrons. electrons are located around the nucleus in certain energy levels and space areas called orbitals. the position of electrons in an atom is characterized by four quantum numbers: principal quantum number (n) – indicates the energy level of the electron and its average distance from the nucleus. orbital quantum number (l) – determines the shape of the orbital (s, p, d, f). magnetic quantum number (m) – indicates the orientation of the orbital in space. spin quantum number (ms) – indicates the direction of rotation of the electron around its axis (+½ or −½).

The periodic law states that the physical and chemical properties of elements change periodically with increasing atomic number. this law is the basis for the placement of elements in the periodic system. the periodic table is a table of elements arranged according to their atomic numbers. the system consists of periods (horizontal rows) and groups (vertical columns). since the elements in the same group have a similar electronic structure, their chemical properties are also similar. the chemical properties of an atom are determined by its electronic structure, especially valence electrons located in the outer energy level. electrons are arranged in energy levels and orbitals according to the aufbau principle, pauli exclusion principle and hund's rule. n = 1 n = 2 n = 3 n = 4 1s 2s 2p

The main types of chemical bonds are: ionic bond - formed between oppositely charged ions as a result of the complete transfer of an electron from one atom to another. covalent bonds are formed as a result of atoms sharing a common pair of electrons. there are non-polar and polar types of covalent bonds. metallic bond - formed between metal atoms and freely moving electrons and provides the characteristic properties of metals. hydrogen bond is a relatively weak intermolecular interaction between a hydrogen atom and atoms with high electronegativity (f, o, n).

Chemical kinetics is the branch of chemistry that studies the rate at which chemical reactions occur, the factors affecting this rate, and the mechanism of the reaction. the rate of a reaction is characterized by the change in concentration of the reactants or products over a certain period of time. the speed of a chemical reaction depends on various factors: the nature of the reactants, their density, temperature, pressure (in gas reactions), surface area, and the presence of a catalyst. an increase in temperature increases the kinetic energy of the particles and speeds up the reaction by increasing the number of effective collisions. a catalyst lowers the activation energy and makes the reaction go faster. chemical equilibrium is a dynamic state that occurs when the rates of forward and reverse reactions are equal in reversible reactions. at this time, although the concentration of substances remains constant, reactions continue in both directions.

Gestural reactions are divided into two groups, rotating and non-rotating, according to the direction of travel. irreversible reactions proceed only in one direction, and the reaction products cannot be converted back into the original substances or proceed very poorly. in these reactions, the reactants are converted into complete or nearly complete products. reversible reactions are reactions that can go both straight and in the opposite direction. these reactions are usually indicated by the symbol ⇌. after a certain time, the rates of direct and reverse reactions become equal and chemical equilibrium is established. chemical equilibrium is the state of the system in reversible reactions in which the rate of the forward reaction is equal to the rate of the reverse reaction. at this time, the concentration of substances remains constant, but the reactions continue at the micro level.

Electrochemical processes are processes that occur due to the transfer and acceptance of electrons during chemical reactions. these processes are based on oxidation-reduction reactions. the electron-donating substance is oxidized, and the electron-accepting substance is reduced. electrode potential is the potential difference between the metal electrode and its salt solution. this potential depends on the ability of metal atoms to donate electrons or their ions to accept electrons. the standard electrode potential is the electrode potential measured under certain conditions (25°c temperature, 1 mol/l concentration of ions and 1 atm pressure). these values ​​are used to compare the activity of metals. the hydrogen electrode is the main reference electrode adopted in the measurement of standard electrode potentials. the potential of the standard hydrogen electrode is assumed to be 0 v. the potentials of other metals are determined by comparison with it. the voltage order of metals (electrochemical order) is the arrangement of metals based on standard electrode potentials. meanwhile: metals with a more negative potential are more prone to donating electrons and are more active. metals with a more positive potential tend to accept electrons and are less active.

Electrolysis is an oxidation-reduction process in an electrolyte solution or alloy under the influence of electric current. during electrolysis, electrical energy is converted into chemical energy. two electrodes are involved in the process: cathode (−) is the electrode where cations receive electrons and are reduced. anode (+) is an electrode where anions give electrons and are oxidized. laws of electrolysis (faraday's laws): faraday's i law - the mass of the substance released at the electrode during electrolysis is directly proportional to the amount of electric charge passing through the solution. faraday's II law - when the same amount of electric charge is passed through different electrolytes, the masses of the separated substances are proportional to their chemical equivalents. galvanic cells are electrochemical devices that convert chemical energy into electrical energy. in these elements, an electric current is generated as a result of a spontaneous oxidation-reduction reaction. in a galvanic cell: an oxidation process takes place at the anode. a reduction process takes place at the cathode.

Natural compounds of metals exist in nature mainly in the form of ores. metals are found free or in the form of various chemical compounds - oxides, sulfides, carbonates, halides. for example, iron is found in oxide ores and aluminum in bauxite. the purchase of metals is carried out through the processing and refining of ores. main methods: pyrometallurgy - obtaining metal by heating and reduction at high temperature. hydrometallurgy - method of separation of metals from solutions. electrometallurgy - extraction and purification of metals by electrolysis. general properties of metals: they conduct electricity and heat well. they have a shiny surface. they have the ability to be beaten and stretched. most are solid (mercury is an exception). chemical properties depend on the activity of the metal. application of metals: iron and steel are used in construction, machinery and transportation. aluminum is used in aviation and packaging because it is light and corrosion resistant. copper is widely used in making electric wires. gold, silver and platinum are used in jewelry and technology. corrosion protection of metals aims to prevent metals from disintegrating under the influence of the external environment. main methods: protective coatings (paint, varnish, metal coatings). electrochemical protection (using sacrificial anodes). alloying (adding resistant elements to metal). use of corrosion inhibitors. conclusion metals occur mainly in the form of ores in nature and are obtained by various metallurgical methods. the physical and chemical properties of metals allow their wide application in industry and technology. various metals play an important role in construction, energy, transportation, electronics and other fields. corrosion reduces the service life of metals, so it is important to apply protective methods. studying the acquisition, properties and methods of protection of metals is of great importance for the development of modern industry. get smarter responses, upload files now

Beryllium (be) and magnesium (mg) are metals included in the group of light construction materials. they are widely used in modern technology because they have low density, high strength and special physico-chemical properties. beryllium (be) natural compounds: beryllium occurs mainly in the minerals beryl (be₃al₂si₆o₁₈) and phenakite (be₂sio₄). production: beryllium ores are processed to obtain beryllium oxide (beo). beo is then reduced with magnesium or metal beryllium is obtained by electrolysis of its molten salts. properties: very light and strong metal. it is resistant to high temperatures. it is resistant to corrosion. it is important as a special nuclear material because it conducts neutrons well. it is a hard and malleable metal. application: in the aviation and space industry. in nuclear engineering. in the preparation of special alloys. in some parts of electronic devices. magnesium (mg) natural compounds: magnesium is found in nature mainly in the form of minerals: magnesite (mgco₃), dolomite (caco₃·mgco₃), carnallite (kcl·mgcl₂·6h₂o). extraction: magnesium is mainly obtained by electrolysis of molten magnesium chloride (mgcl₂). it can also be obtained by thermal treatment of magnesium compounds. properties: silver-white, very light metal. the density is low. it is easy to process. it is an active metal, prone to oxidation. forms light and strong alloys with various metals. application: in the production of aircraft and car parts. in light structural alloys. as a reducing agent in metallurgy. it is used as a bright light source in pyrotechnics. conclusion beryllium and magnesium are light, strong and structural materials with special properties. these metals are mainly obtained from natural minerals by metallurgy and electrolysis methods. their low density and high strength make them valuable materials in aviation, space industry and engineering. the use of be and mg alloys allows the development of modern light and durable constructions.

Aluminum (al) and titanium (ti) are light and strong metals widely used in modern industry. they are of great importance as construction materials due to their high strength, corrosion resistance and special physical properties. aluminum (al) natural compounds: aluminum does not exist free in nature, it is mainly found in the form of ores: bauxite - al₂o₃·nh₂o cryolite - na₃alf₆ corundum - al₂o₃ production: aluminum is mainly obtained from bauxite. first, aluminum oxide (al₂o₃) is obtained. then pure aluminum is obtained as a result of electrolysis of al₂o₃ in molten cryolite. properties: silver-white, light metal. conducts electricity and heat well. it is resistant to corrosion, because a protective al₂o₃ layer is formed on its surface. it is easily processed and forms alloys. application: in the aviation and space industry. in electrical wiring. in building materials. in the preparation of household items and various alloys. titanium (ti) natural compounds: titanium is mainly found in the following minerals: rutile – tio₂ ilmenite – fetio₃ production: titanium(iv) chloride (ticl₄) is first obtained from titanium oxides. metal titanium is obtained by reduction of ticl₄ with magnesium (kroll method). properties: light but very strong metal. resistant to corrosion and high temperature. it has high biological compatibility. its mechanical strength is higher than aluminum. application: in the development of aircraft and spacecraft. in corrosion-resistant equipment in the chemical industry. as an implant material in medicine. in the production of strong and light alloys. conclusion aluminum and titanium occupy an important place among lightweight construction materials. these metals are mainly obtained from oxides and minerals by metallurgical methods. aluminum stands out for its lightness and corrosion resistance, and titanium for its high strength and durability. both metals are widely used in aviation, space technology, construction, engineering and other modern industries.

Cu (cu) and zinc (zn) are non-ferrous metals widely used in industry. they are considered important structural and technical materials due to their good electrical conductivity, corrosion resistance and ability to form various alloys. copper (cu) natural compounds: copper occurs in nature both free and as minerals: chalcopyrite – cufes₂ chalcosine – cu₂s malachite – cu₂co₃(oh)₂ cuprite – cu₂o production: copper is mainly obtained from sulphide ores. after the ore is enriched, it undergoes roasting and smelting processes. electrolytic refining is used to obtain purer copper. properties: reddish colored, soft and malleable metal. conducts electricity and heat very well. relatively resistant to corrosion. it forms alloys with various metals. application: in the preparation of electric wires and cables. in the electronics industry. in pipes and heat exchangers. in the production of bronze (cu + sn) and brass (cu + zn) alloys. zinc (zn) natural compounds: zinc occurs mainly in the form of ores in nature: sphalerite (zinc sulfide) – zns smithsonite – znco₃ zincite – zno production: zinc ores are enriched and zinc oxide is obtained by roasting. zinc oxide is reduced with carbon or zinc metal is obtained by electrolysis of zinc salts. properties: it is a bluish-white metal. it has moderate strength. it is resistant to corrosion as it forms a protective oxide layer on its surface. forms easy alloys. application: zinc coating and corrosion protection of iron. in the preparation of brass alloy. in batteries. in the chemical and metallurgical industry.

Chromium (cr) and manganese (mn) belong to the group of transition metals and are important metals in industry. they are mainly used in the preparation of strong and durable alloys, in metallurgy and in various technical fields. chromium (cr) natural compounds: chromium occurs in nature mainly in the form of ores: chromite – fecr₂o₄ crocoite – pbcro₄ production: chromium(iii)-oxide (cr₂o₃) is first obtained from chromite ore. cr₂o₃ is reduced with aluminum to obtain metallic chromium (aluminothermy method). high purity chromium can also be obtained by electrolysis. properties: silver-white, hard and shiny metal. it is resistant to high temperatures. it has high resistance to corrosion. it forms a protective oxide layer on its surface

Iron (fe) is widely distributed in nature and one of the most widely used metals in industry. it belongs to the group of transition metals and is mainly found in various ores. iron and its alloys are considered important materials for engineering, construction and other industries. natural compounds of iron: iron is found in nature mainly in the form of oxide, carbonate and sulfide ores: magnetite - fe₃o₄ hematite - fe₂o₃ limonite - fe₂o₃·nh₂o siderite - feco₃ pyrite - fes₂

Law of conservation of mass of matter. the law of stability of composition. law of equivalents. the law of mass proportions. the law of volume proportions. avogadro's law.

Electron orbitals. principal quantum number. orbital quantum number. magnetic quantum number. spin quantum number. distribution of electrons in quantum levels. pauli principle.

Periodic law and periodic system. mosley's law. serial number of elements. the structure of the periodic table. the relationship between the electronic structure of the atom and the periodic law. periodic change of properties of elements.

The rate of a chemical reaction is the rate of change of the amount or concentration of substances during a reaction in a certain time. the reaction rate can increase or decrease depending on various factors. homogeneous reactions occur between substances in the same aggregate state (for example, gas-gas or solute-solute reactions). in these reactions, the rate is the same throughout the volume. heterogeneous reactions take place between substances in different aggregates (for example, solid-liquid, solid-gas). the speed of such reactions mainly depends on the processes occurring at the contact surface of substances. the main factors affecting the reaction rate: nature of reactants; density (concentration) of substances; temperature; contact surface area (especially in heterogeneous reactions)

Reversible and non-reversible reactions. displacement of equilibrium. equilibrium constant. factors affecting chemical equilibrium. le chatelier principle. temperature. effect of solidity, pressure on equilibrium.

Vapor pressure and phase transformations of solutions. raoult's first law. freezing and boiling point of solution. raoult's second law. osmosis phenomenon. osmosis pressure and van't-hoff's law.

Electrode potential. . standard electrode potential or voltage order. hydrogen electrode. information about the normal electrode potentials of metals.

Electrolysis process. scheme of electrolysis. anode and cathode electrodes. electrolysis of aqueous solutions of salts. laws of electrolysis: faraday's i and II laws.

Pyrometallurgy. hydrometallurgy, electrometallurgy. methods. purchase of metals in pure and highly pure state. electrolysis, vacuum extraction (distillation), thermal decomposition of volatile compounds.

. electronegativity. ionic communication. ions forming communication. ionic compounds. metal communication. directionality of metal connection and

Zinc equivalent is the amount of zinc that replaces 1 gram-hydrogen in a chemical reaction. the equivalent mass is calculated by dividing the atomic mass of the metal by its valence. since zinc is a divalent metal: e(zn)= v(zn) a(zn) here: a(zn) — the relative atomic mass of zinc (≈65.38) v(zn) — the valence of zinc (2) e(zn)= 2 65.38 ​ =32.69 to determine the equivalent of zinc, the volume of hydrogen gas released from the reaction of zinc with acid is usually measured: zn+2hcl→zncl 2 ​ +h 2 ​ ↑ the equivalent mass of zinc is calculated based on the amount of hydrogen released during the reaction. the result

The basic gas laws study the relationship between the pressure, volume, temperature, and amount of matter of gases. basic gas laws include boyle–marriott's law, gay–lussac's law, and avogadro's law. according to the boyle–marriott law, the volume of a gas is inversely proportional to its pressure when the temperature remains constant. according to the gay-lussac law, the volume of a gas increases as the temperature increases when the pressure is constant. according to avogadro's law, equal volumes of different gases contain the same number of molecules at the same temperature and pressure. determination of the molecular mass of carbon dioxide (co₂) is based on the calculation of the molar mass of the gas. for this, the mass, volume, temperature and pressure of the gas are determined and the ideal gas equation is used: [ pv=nrt ] here: p — gas pressure, v — gas volume, n — amount of matter, r — universal gas constant, t — absolute temperature. the molar mass of carbon dioxide is calculated by the following formula: [ m=\frac{mrt}{pv} ] the relative molecular mass of a co₂ molecule is: [ m_r(co_2)=12+2 \times 16=44 ].

Chemical kinetics is the branch of chemistry that studies the rate of chemical reactions, the factors affecting the rate, and the mechanism by which the reactions proceed. the rate of a chemical reaction indicates the change in concentration of substances involved in the reaction during a unit time. the reaction rate depends on the nature of substances and various external factors. the main factors affecting the rate of chemical reactions: nature of substances - different substances react at different rates. solidity - as the density of reactants increases, the number of particle collisions increases and the reaction rate increases. temperature - when the temperature increases, the movement of particles accelerates and ef

Since magnesium and aluminum are active metals, they are difficult to obtain by conventional chemical reduction methods. these metals are mainly obtained by the electrometallurgical method, that is, by electrolysis of molten salts. obtaining magnesium magnesium is mainly obtained by electrolysis of magnesium chloride (mgcl₂) alloy: [ mgcl_2 \rightarrow mg^{2+}+2cl^- ] at the cathode: [ mg^{2+}+2e^- \rightarrow mg ] at the anode: [ 2cl^- -2e^- \rightarrow cl_2 ] as a result, metal magnesium is released at the cathode, and chlorine gas is released at the anode. aluminum extraction aluminum is mainly obtained by electrolysis of alumina (al₂o₃) from bauxite ore in molten cryolite (na₃alf₆). at the cathode: [ al^{3+}+3e^- \rightarrow al ] at the anode: [

Chromium (cr) and copper (cu) are metals widely used in industry. the methods of their acquisition depend on the activity of metals and the composition of their ores. obtaining chromium since chromium is an active metal, it is mainly obtained by metallothermal method. chromium oxide (cr₂o₃) is obtained from chromium ore chromite (fecr₂o₄) and then reduced with aluminum: [ cr_2o_3+2al \rightarrow 2cr+al_2o_3 ] this process is called aluminothermy. as a result, pure chromium metal is obtained at high temperature.