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Oxides- OXIDES, compounds of chemical elements (except fluorine) with oxygen. When interacting with water, they form bases (basic oxides) or acids (acidic oxides); many oxides are amphoteric. Most oxides are solids under normal conditions... ... Illustrated Encyclopedic Dictionary

Oxide (oxide, oxide) binary compound chemical element with oxygen in the −2 oxidation state, in which oxygen itself is bound only to the less electronegative element. The chemical element oxygen is second in electronegativity... ... Wikipedia

Metal oxides- These are compounds of metals with oxygen. Many of them can combine with one or more water molecules to form hydroxides. Most oxides are basic because their hydroxides behave like bases. However, some... ... Official terminology

oxides- The combination of a chemical element with oxygen. According to their chemical properties, all oxides are divided into salt-forming (for example, Na2O, MgO, Al2O3, SiO2, P2O5, SO3, Cl2O7) and non-salt-forming (for example, CO, N2O, NO, H2O). Salt-forming oxides are divided into... ... Technical Translator's Guide

OXIDES- chem. compounds of elements with oxygen (outdated name oxides); one of the most important classes of chemistry. substances. O. are most often formed during the direct oxidation of simple and complex substances. Eg. Oxidation is formed during the oxidation of hydrocarbons.... ... Big Polytechnic Encyclopedia

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Key Facts- Oil is a flammable liquid, which is a complex mixture of hydrocarbons. Various types oils differ significantly in chemical and physical properties: in nature it is presented both in the form of black bitumen asphalt and in the form... ... Oil and Gas Microencyclopedia

Key Facts- Oil is a flammable liquid, which is a complex mixture of hydrocarbons. Different types of oil differ significantly in chemical and physical properties: in nature it is presented both in the form of black bitumen asphalt and in the form... ... Oil and Gas Microencyclopedia

Oxides- a combination of a chemical element with oxygen. According to their chemical properties, all oxides are divided into salt-forming (for example, Na2O, MgO, Al2O3, SiO2, P2O5, SO3, Cl2O7) and non-salt-forming (for example, CO, N2O, NO, H2O). Salt-forming oxides... ... Encyclopedic Dictionary in metallurgy

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• , Gusev Alexander Ivanovich. Nonstoichiometry, caused by the presence of structural vacancies, is widespread in solid-phase compounds and creates the prerequisites for disordered or ordered distribution...
• Nonstoichiometry, disorder, short-range and long-range order in a solid, Gusev A.I.. Nonstoichiometry, caused by the presence of structural vacancies, is widespread in solid-phase compounds and creates the prerequisites for disordered or ordered distribution...

SECTION II. INORGANIC CHEMISTRY

7. Main classes of inorganic compounds

7.1. Oxides

Oxides are binary compounds of elements with Oxygen, in which it exhibits an oxidation state- 2. Characteristic Signs oxides:

oxidation state of oxygen- - 2;

Oxygen atoms are not connected to each other, but are connected only to atoms of other elements;

the atoms of the element forming the oxide have the same oxidation state 1.

Graphic formulas of oxides

Valence of elements	Graphic formula

Not all binary oxygen compounds are oxides:

Substance	Formula	Graphic formula	Oxidation state of oxygen
hydrogen peroxide	H2O2	H-O-O-H
sodium peroxide	Na2O2	Na-O-O-Na
oxygen fluoride	OF 2	F-O-F

Based on their chemical nature, oxides are divided into non-saline and saline.

Non-saline oxides - NO, N2O, CO, SiO - these are oxides that are classified as reactive compounds, but salts are not formed during reactions. They do not react with water, acids and bases under normal conditions (hence, they are conditionally classified as oxides).

Salt oxides are oxides that form salts. Salt oxides are divided into basic ones (K 2 O, BaO, MgO, FeO), acidic (SO 2, SO 3, N 2 O 5, P 2 O 5) and amphoteric (ZnO, Al 2 O 3, Cr 2 O 3, BeO).

Nomenclature of oxides

The name of oxides consists of the name of the element, after which, when the element exhibits several states of oxidation, the degree of oxidation is indicated in parentheses in Roman numerals and the word “oxide” is added. For example:

K 2 O - potassium oxide;

Fe2O3 - ferrum(III) oxide;

С u 2 O - cuprum(I) oxide;

MgO - magnesium oxide;

P 2 O 5 - phosphorus (V) oxide;

A l 2 O 3 - aluminum oxide;

CO - carbon(II) oxide.

Some oxides that have long been known to man have trivial names: CaO - quicklime, C O2 - carbon dioxide, SO 2 - sulfur dioxide.

Obtaining oxides

1. Interaction simple substances(metals and non-metals) with oxygen:

2. Oxidation of complex substances:

3. Thermal decomposition:

basics:

salts:

amphoteric hydroxides:

Some acids:

4. During some other reactions:

______________________________________________________

1 Double "oxide" ( FeFe2)O4 contains Ferum with different oxidation states (+2 and +3) and, when interacting with acidic oxides, forms two different salts.

7.1.1. Basic oxides

Basic oxides are oxides whose hydrates are bases. All basic oxides are oxides of metal elements that exhibit low oxidation states (+1, +2). To basic oxides include:

oxides of metal elements of the main subgroups I and II groups (except Be);

oxides of monovalent elements, divalent, with the exception of BeO, ZnO, Г b O, which are amphoteric;

oxides of transition metal elements in low oxidation states(NiO, FeO, MnO, CrO).

Basic oxides correspond to bases:

Na 2 O - NaOH

MgO - Mg(OH) 2

FeO - Fe (OH) 2

BaO - Ba (OH) 2

CrO - Cr (OH) 2

Type chemical bond in basic oxides it is predominantly ionic.

Chemical properties basic oxides

1. Interaction with acids to form salts:

2. Interaction with acid oxides to form salts:

3. Interaction with water. Only oxides of alkali and alkaline earth metal elements react with water, forming alkalis:

4. Interaction with amphoteric oxides. The reaction occurs during fusion. The amphoteric oxide exhibits acidic properties in this reaction:

5. Interaction with amphoteric bases. The reaction occurs during fusion:

Oxides are substances in which the molecules consist of an oxygen atom with oxidation state - 2 and atoms of some second element.

Oxides are formed directly by the interaction of oxygen with another substance or indirectly by the decomposition of bases, salts, and acids. This type of compound is very common in nature and can exist in the form of gas, liquid or B earth's crust there are also oxides. So, sand, rust, and even ordinary water - that’s all

There are both salt-forming and non-salt-forming oxides. Salt-forming as a result chemical reaction give salt. These include oxides of non-metals and metals, which in reaction with water form an acid, and in reaction with a base - salts, normal and acidic. Salt-forming agents include, for example,

Accordingly, it is impossible to obtain salt from non-salt-forming substances. Examples include dinitrogen oxide and

Salt-forming oxides are divided, in turn, into basic, acidic and amphoteric. Let's talk in more detail about the main ones.

So, basic oxides are oxides of some metals, the corresponding hydroxides belong to the class of bases. That is, when interacting with acid, such substances form water and salt. For example, these are K2O, CaO, MgO, etc. Under normal conditions, basic oxides are solid crystalline formations. The degree of oxidation of metals in such compounds, as a rule, does not exceed +2 or rarely +3.

Chemical properties of basic oxides

1. Reaction with acid

It is in the reaction with an acid that the oxide exhibits its basic properties, so a similar experiment can prove the type of a particular oxide. If salt and water are formed, then it is a basic oxide. Acidic oxides in such a reaction form an acid. And amphoteric ones can exhibit either acidic or basic properties - it depends on the conditions. These are the main differences between non-salt-forming oxides.

2. Reaction with water

Those oxides that are formed by metals from the electrical voltage range that are in front of magnesium interact with water. When reacting with water they form soluble bases. This is a group of alkaline earth oxides (barium oxide, lithium oxide, etc.). Acidic oxides form acid in water, while amphoteric oxides do not react to water.

3. Reaction with amphoteric and acidic oxides

Chemically opposite substances react with each other, forming salts. For example, basic oxides can interact with acidic ones, but do not react with other representatives of their group. The most active are the oxides of alkali metals, alkaline earths and magnesium. Even under normal conditions, they fuse with solid amphoteric oxides and with solid and gaseous acidic oxides. When reacting with acidic oxides, they form the corresponding salts.

But the basic oxides of other metals are less active and practically do not react with gaseous (acidic) oxides. They can only undergo an addition reaction when fused with solid acid oxides.

4. Redox properties

Oxides of active alkali metals do not exhibit pronounced reducing or oxidizing properties. And, on the contrary, oxides of not so active metals can be reduced by coal, hydrogen, ammonia or carbon monoxide.

Preparation of basic oxides

1. Decomposition of hydroxides: When heated, insoluble bases decompose into water and a basic oxide.

2. Oxidation of metals: alkali metal when burned in oxygen, it forms a peroxide, which then, upon reduction, forms a basic oxide.

Non-salt-forming (indifferent, indifferent) oxides CO, SiO, N 2 0, NO.

Salt-forming oxides:

Basic. Oxides whose hydrates are bases. Metal oxides with oxidation states +1 and +2 (less often +3). Examples: Na 2 O - sodium oxide, CaO - calcium oxide, CuO - copper (II) oxide, CoO - cobalt (II) oxide, Bi 2 O 3 - bismuth (III) oxide, Mn 2 O 3 - manganese (III) oxide ).

Amphoteric. Oxides whose hydrates are amphoteric hydroxides. Metal oxides with oxidation states +3 and +4 (less often +2). Examples: Al 2 O 3 - aluminum oxide, Cr 2 O 3 - chromium (III) oxide, SnO 2 - tin (IV) oxide, MnO 2 - manganese (IV) oxide, ZnO - zinc oxide, BeO - beryllium oxide.

Acidic. Oxides whose hydrates are oxygen-containing acids. Non-metal oxides. Examples: P 2 O 3 - phosphorus (III) oxide, CO 2 - carbon oxide (IV), N 2 O 5 - nitrogen oxide (V), SO 3 - sulfur oxide (VI), Cl 2 O 7 - chlorine oxide ( VII). Metal oxides with oxidation states +5, +6 and +7. Examples: Sb 2 O 5 - antimony (V) oxide. CrOz - chromium (VI) oxide, MnOz - manganese (VI) oxide, Mn 2 O 7 - manganese (VII) oxide.

Change in the nature of oxides with increasing oxidation state of the metal

Physical properties

Oxides are solid, liquid and gaseous, of different colors. For example: copper (II) oxide CuO black, calcium oxide CaO white- solids. Sulfur oxide (VI) SO 3 is a colorless volatile liquid, and carbon monoxide (IV) CO 2 is a colorless gas under ordinary conditions.

Physical state

CaO, CuO, Li 2 O and other basic oxides; ZnO, Al 2 O 3, Cr 2 O 3 and other amphoteric oxides; SiO 2, P 2 O 5, CrO 3 and other acid oxides.

SO 3, Cl 2 O 7, Mn 2 O 7, etc.

Gaseous:

CO 2, SO 2, N 2 O, NO, NO 2, etc.

Solubility in water

Soluble:

a) basic oxides of alkali and alkaline earth metals;

b) almost all acid oxides (exception: SiO 2).

Insoluble:

a) all other basic oxides;

b) all amphoteric oxides

Chemical properties

1. Acid-base properties

Common properties of basic, acidic and amphoteric oxides are acid-base interactions, which are illustrated by the following diagram:

(only for oxides of alkali and alkaline earth metals) (except SiO 2).

Amphoteric oxides, having the properties of both basic and acidic oxides, interact with strong acids and alkalis:

2. Redox properties

If an element has a variable oxidation state (s.o.), then its oxides with low s. O. can exhibit reducing properties, and oxides with high c. O. - oxidative.

Examples of reactions in which oxides act as reducing agents:

Oxidation of oxides with low c. O. to oxides with high c. O. elements.

2C +2 O + O 2 = 2C +4 O 2

2S +4 O 2 + O 2 = 2S +6 O 3

2N +2 O + O 2 = 2N +4 O 2

Carbon (II) monoxide reduces metals from their oxides and hydrogen from water.

C +2 O + FeO = Fe + 2C +4 O 2

C +2 O + H 2 O = H 2 + 2C +4 O 2

Examples of reactions in which oxides act as oxidizing agents:

Reduction of oxides with high o. elements to oxides with low c. O. or to simple substances.

C +4 O 2 + C = 2C +2 O

2S +6 O 3 + H 2 S = 4S +4 O 2 + H 2 O

C +4 O 2 + Mg = C 0 + 2MgO

Cr +3 2 O 3 + 2Al = 2Cr 0 + 2Al 2 O 3

Cu +2 O + H 2 = Cu 0 + H 2 O

The use of oxides of low-active metals for the oxidation of organic substances.

Some oxides in which the element has an intermediate c. o., capable of disproportionation;

For example:

2NO 2 + 2NaOH = NaNO 2 + NaNO 3 + H 2 O

Methods of obtaining

1. Interaction of simple substances - metals and non-metals - with oxygen:

4Li + O 2 = 2Li 2 O;

2Cu + O 2 = 2CuO;

4P + 5O 2 = 2P 2 O 5

2. Dehydration of insoluble bases, amphoteric hydroxides and some acids:

Cu(OH) 2 = CuO + H 2 O

2Al(OH) 3 = Al 2 O 3 + 3H 2 O

H 2 SO 3 = SO 2 + H 2 O

H 2 SiO 3 = SiO 2 + H 2 O

3. Decomposition of some salts:

2Cu(NO 3) 2 = 2CuO + 4NO 2 + O 2

CaCO 3 = CaO + CO 2

(CuOH) 2 CO 3 = 2CuO + CO 2 + H 2 O

4. Oxidation of complex substances with oxygen:

CH 4 + 2O 2 = CO 2 + H 2 O

4FeS 2 + 11O 2 = 2Fe 2 O 3 + 8SO 2

4NH 3 + 5O 2 = 4NO + 6H 2 O

5. Reduction of oxidizing acids with metals and non-metals:

Cu + H 2 SO 4 (conc) = CuSO 4 + SO 2 + 2H 2 O

10HNO 3 (conc) + 4Ca = 4Ca(NO 3) 2 + N 2 O + 5H 2 O

2HNO 3 (diluted) + S = H 2 SO 4 + 2NO

6. Interconversions of oxides during redox reactions (see redox properties of oxides).

Properties of oxides

Oxides are complex chemical substances that are chemical compounds simple elements with oxygen. They happen salt-forming And non-salt forming. In this case, there are 3 types of salt-forming agents: main(from the word "foundation"), acidic And amphoteric.
An example of oxides that do not form salts are: NO (nitric oxide) - is a colorless, odorless gas. It is formed during a thunderstorm in the atmosphere. CO (carbon monoxide) is an odorless gas produced by the combustion of coal. It is commonly called carbon monoxide. There are other oxides that do not form salts. Now let's take a closer look at each type of salt-forming oxides.

Basic oxides

Basic oxides- These are complex chemical substances related to oxides that form salts upon chemical reaction with acids or acidic oxides and do not react with bases or basic oxides. For example, the main ones include the following:
K 2 O (potassium oxide), CaO (calcium oxide), FeO (ferrous oxide).

Let's consider chemical properties of oxides with examples

1. Interaction with water:
- interaction with water to form a base (or alkali)

CaO+H 2 O → Ca(OH) 2 (known lime slaking reaction, which releases large quantities warmth!)

2. Interaction with acids:
- interaction with acid to form salt and water (salt solution in water)

CaO+H 2 SO 4 → CaSO 4 + H 2 O (Crystals of this substance CaSO 4 are known to everyone under the name “gypsum”).

3. Interaction with acid oxides: salt formation

CaO+CO 2 → CaCO 3 (Everyone knows this substance - ordinary chalk!)

Acidic oxides

Acidic oxides- these are complex chemical substances related to oxides that form salts upon chemical interaction with bases or basic oxides and do not interact with acidic oxides.

Examples of acidic oxides can be:

CO 2 (well-known carbon dioxide), P 2 O 5 - phosphorus oxide (formed by the combustion of white phosphorus in air), SO 3 - sulfur trioxide - this substance is used to produce sulfuric acid.

Chemical reaction with water

CO 2 +H 2 O → H 2 CO 3 - this substance is carbonic acid - one of the weak acids, it is added to carbonated water to create gas “bubbles”. With increasing temperature, the solubility of gas in water decreases, and its excess comes out in the form of bubbles.

Reaction with alkalis (bases):

CO 2 +2NaOH→ Na 2 CO 3 +H 2 O- the resulting substance (salt) is widely used in the household. Its name - soda ash or washing soda - is an excellent detergent for burnt pots, grease, and burnt marks. I do not recommend working with bare hands!

Reaction with basic oxides:

CO 2 +MgO→ MgCO 3 - the resulting salt is magnesium carbonate - also called “bitter salt”.

Amphoteric oxides

Amphoteric oxides- these are complex chemical substances, also related to oxides, which form salts during chemical interaction with acids (or acid oxides) and grounds (or basic oxides). The most common use of the word "amphoteric" in our case refers to metal oxides.

Example amphoteric oxides may be:

ZnO - zinc oxide ( white powder, often used in medicine for the manufacture of masks and creams), Al 2 O 3 - aluminum oxide (also called “alumina”).

The chemical properties of amphoteric oxides are unique in that they can enter into chemical reactions with both bases and acids. For example:

Reaction with acid oxide:

ZnO+H 2 CO 3 → ZnCO 3 + H 2 O - The resulting substance is a solution of the salt “zinc carbonate” in water.

Reaction with bases:

ZnO+2NaOH→ Na 2 ZnO 2 +H 2 O - the resulting substance is a double salt of sodium and zinc.

Obtaining oxides

Obtaining oxides produce in various ways. This can happen through physical and chemical means. The most in a simple way is the chemical interaction of simple elements with oxygen. For example, the result of the combustion process or one of the products of this chemical reaction are oxides. For example, if a hot iron rod, and not only iron (you can take zinc Zn, tin Sn, lead Pb, copper Cu - basically whatever is at hand) is placed in a flask with oxygen, then a chemical reaction of iron oxidation will occur, which accompanied by a bright flash and sparks. The reaction product will be black iron oxide powder FeO:

2Fe+O 2 → 2FeO

Chemical reactions with other metals and non-metals are completely similar. Zinc burns in oxygen to form zinc oxide

2Zn+O 2 → 2ZnO

The combustion of coal is accompanied by the formation of two oxides at once: carbon monoxide and carbon dioxide

2C+O 2 → 2CO - formation of carbon monoxide.

C+O 2 → CO 2 - formation of carbon dioxide. This gas is formed if there is more than enough oxygen, that is, in any case, the reaction first occurs with the formation of carbon monoxide, and then the carbon monoxide is oxidized, turning into carbon dioxide.

Obtaining oxides can be done in another way - through a chemical decomposition reaction. For example, to obtain iron oxide or aluminum oxide, it is necessary to calcinate the corresponding bases of these metals over a fire:

Fe(OH) 2 → FeO+H 2 O

Solid aluminum oxide - mineral corundum Iron(III) oxide. The surface of the planet Mars is reddish-orange in color due to the presence of iron (III) oxide in the soil. Solid aluminum oxide - corundum

2Al(OH) 3 → Al 2 O 3 +3H 2 O,
as well as during the decomposition of individual acids:

H 2 CO 3 → H 2 O+CO 2 - decomposition of carbonic acid

H 2 SO 3 → H 2 O+SO 2 - decomposition sulfurous acid

Obtaining oxides can be made from metal salts with strong heating:

CaCO 3 → CaO+CO 2 - calcination of chalk produces calcium oxide (or quicklime) and carbon dioxide.

2Cu(NO 3) 2 → 2CuO + 4NO 2 + O 2 - in this decomposition reaction two oxides are obtained at once: copper CuO (black) and nitrogen NO 2 (it is also called brown gas because of its really brown color).

Another way in which oxides can be produced is through redox reactions.

Cu + 4HNO 3 (conc.) → Cu(NO 3) 2 + 2NO 2 + 2H 2 O

S + 2H 2 SO 4 (conc.) → 3SO 2 + 2H 2 O

Chlorine oxides

ClO2 molecule Cl 2 O 7 molecule Nitrous oxide N2O Nitrogenous anhydride N 2 O 3 Nitric anhydride N 2 O 5 Brown gas NO 2

The following are known chlorine oxides: Cl 2 O, ClO 2, Cl 2 O 6, Cl 2 O 7. All of them, with the exception of Cl 2 O 7, are yellow or orange in color and are unstable, especially ClO 2, Cl 2 O 6. All chlorine oxides are explosive and are very strong oxidizing agents.

Reacting with water, they form the corresponding oxygen-containing and chlorine-containing acids:

So, Cl 2 O - acid chlorine oxide hypochlorous acid.

Cl 2 O + H 2 O → 2HClO - Hypochlorous acid

ClO2 - acid chlorine oxide hypochlorous and hypochlorous acid, since during a chemical reaction with water it forms two of these acids at once:

ClO 2 + H 2 O→ HClO 2 + HClO 3

Cl 2 O 6 - too acid chlorine oxide perchloric and perchloric acids:

Cl 2 O 6 + H 2 O → HClO 3 + HClO 4

And finally, Cl 2 O 7 - a colorless liquid - acid chlorine oxide perchloric acid:

Cl 2 O 7 + H 2 O → 2HClO 4

Nitrogen oxides

Nitrogen is a gas that forms 5 different compounds with oxygen - 5 nitrogen oxides. Namely:

N2O- nitric oxide. Its other name is known in medicine as laughing gas or nitrous oxide- It is colorless, sweetish and pleasant to the taste of gas.
- NO - nitrogen monoxide- a colorless, odorless, tasteless gas.
- N 2 O 3 - nitrous anhydride- colorless crystalline substance
- NO 2 - nitrogen dioxide. Its other name is brown gas- the gas really has a brownish-brown color
- N 2 O 5 - nitric anhydride- blue liquid, boiling at a temperature of 3.5 0 C

Of all these listed nitrogen compounds, NO - nitrogen monoxide and NO 2 - nitrogen dioxide are of greatest interest in industry. Nitrogen monoxide(NO) and nitrous oxide N 2 O does not react with water or alkalis. (N 2 O 3) when reacting with water forms a weak and unstable nitrous acid HNO 2, which in air gradually turns into a more stable chemical substance, nitric acid. Let's look at some chemical properties of nitrogen oxides:

Reaction with water:

2NO 2 + H 2 O → HNO 3 + HNO 2 - 2 acids are formed at once: nitric acid HNO 3 and nitrous acid.

Reaction with alkali:

2NO 2 + 2NaOH → NaNO 3 + NaNO 2 + H 2 O - two salts are formed: sodium nitrate NaNO 3 (or sodium nitrate) and sodium nitrite (a salt of nitrous acid).

Reaction with salts:

2NO 2 + Na 2 CO 3 → NaNO 3 + NaNO 2 + CO 2 - two salts are formed: sodium nitrate and sodium nitrite, and carbon dioxide is released.

Nitrogen dioxide (NO 2) is obtained from nitrogen monoxide (NO) using a chemical reaction of combining with oxygen:

2NO + O 2 → 2NO 2

Iron oxides

Iron forms two oxide: FeO - iron oxide(2-valent) - black powder, which is obtained by reduction iron oxide(3-valent) carbon monoxide by the following chemical reaction:

Fe 2 O 3 +CO→ 2FeO+CO 2

This is a basic oxide that reacts easily with acids. It has reducing properties and quickly oxidizes into iron oxide(3-valent).

4FeO +O 2 → 2Fe 2 O 3

Iron oxide(3-valent) - red-brown powder (hematite), which has amphoteric properties (can interact with both acids and alkalis). But the acidic properties of this oxide are so weakly expressed that it is most often used as basic oxide.

There are also so-called mixed iron oxide Fe 3 O 4 . It is formed when iron burns and conducts well electric current and has magnetic properties(it is called magnetic iron ore or magnetite). If iron burns, then as a result of the combustion reaction, scale is formed, consisting of two oxides: iron oxide(III) and (II) valence.

Sulfur oxide

Sulfur dioxide SO 2

Sulfur oxide SO 2 - or sulfur dioxide refers to acid oxides, but does not form acid, although it dissolves perfectly in water - 40 liters of sulfur oxide in 1 liter of water (for ease of preparation chemical equations This solution is called sulfurous acid).

Under normal circumstances, it is a colorless gas with a pungent and suffocating odor of burnt sulfur. At a temperature of only -10 0 C it can be converted into a liquid state.

In the presence of a catalyst - vanadium oxide (V 2 O 5) sulfur oxide attaches oxygen and turns into sulfur trioxide

2SO 2 +O 2 → 2SO 3

Dissolved in water sulfur dioxide- sulfur oxide SO2 - oxidizes very slowly, as a result of which the solution itself turns into sulfuric acid

If sulfur dioxide pass an alkali, for example, sodium hydroxide, through a solution, then sodium sulfite is formed (or hydrosulfite - depending on how much alkali and sulfur dioxide you take)

NaOH + SO 2 → NaHSO 3 - sulfur dioxide taken in excess

2NaOH + SO 2 → Na 2 SO 3 + H 2 O

If sulfur dioxide does not react with water, then why does its aqueous solution give an acidic reaction?! Yes, it does not react, but it itself oxidizes in water, adding oxygen to itself. And it turns out that free hydrogen atoms accumulate in water, which give an acidic reaction (you can check with some indicator!)