Sulfur is located in group VIa of the Periodic Table of Chemical Elements D.I. Mendeleev.
The outer energy level of sulfur contains 6 electrons, which have 3s 2 3p 4. In compounds with metals and hydrogen, sulfur exhibits a negative oxidation state of elements -2, in compounds with oxygen and other active non-metals - positive +2, +4, +6. Sulfur is a typical non-metal; depending on the type of transformation, it can be an oxidizing agent and a reducing agent.

Finding sulfur in nature

Sulfur is found in a free (native) state and bound form.

The most important natural sulfur compounds:

FeS 2 - iron pyrite or pyrite,

ZnS - zinc blende or sphalerite (wurtzite),

PbS - lead luster or galena,

HgS - cinnabar,

Sb 2 S 3 - stibnite.

In addition, sulfur is present in oil, natural coal, natural gases, and natural waters (in the form of sulfate ions and determines the “permanent” hardness of fresh water). A vital element for higher organisms, an integral part of many proteins, is concentrated in the hair.

Allotropic modifications of sulfur

Allotropy- this is the ability of the same element to exist in different molecular forms (molecules contain different numbers of atoms of the same element, for example, O 2 and O 3, S 2 and S 8, P 2 and P 4, etc.).

Sulfur is distinguished by its ability to form stable chains and cycles of atoms. The most stable are S8, which form orthorhombic and monoclinic sulfur. This is crystalline sulfur - a brittle yellow substance.

Open chains have plastic sulfur, a brown substance, which is obtained by sharp cooling of molten sulfur (plastic sulfur becomes brittle after a few hours, acquires a yellow color and gradually turns into rhombic).

1) rhombic - S 8

t°pl. = 113°C; r = 2.07 g/cm 3

The most stable modification.

2) monoclinic - dark yellow needles

t°pl. = 119°C; r = 1.96 g/cm 3

Stable at temperatures above 96°C; under normal conditions it turns into rhombic.

3) plastic - brown rubber-like (amorphous) mass

Unstable, when hardening it turns into a rhombic

Obtaining sulfur

1. The industrial method is smelting the ore using steam.
2. Incomplete oxidation of hydrogen sulfide (with a lack of oxygen):

2H 2 S + O 2 → 2S + 2H 2 O

1. Wackenroeder's reaction:

2H 2 S + SO 2 → 3S + 2H 2 O

Chemical properties of sulfur

Oxidative properties of sulfur
(S 0 + 2ē→ S -2 )

1) Sulfur reacts with alkaline substances without heating:

S + O 2 – t° → S +4 O 2

2S + 3O 2 – t °; pt → 2S +6 O 3

4) (except iodine):

S+Cl2 → S +2 Cl 2

S + 3F 2 → SF 6

With complex substances:

5) with acids - oxidizing agents:

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

S+6HNO3(conc) → H 2 S +6 O 4 + 6NO 2 + 2H 2 O

Disproportionation reactions:

6) 3S 0 + 6KOH → K 2 S +4 O 3 + 2K 2 S -2 + 3H 2 O

7) sulfur dissolves in a concentrated solution of sodium sulfite:

S 0 + Na 2 S +4 O 3 → Na 2 S 2 O 3 sodium thiosulfate

Chemistry lesson on the topic "Sulfur Oxide( VI ). Sulfuric acid."

Khairuddinov Boris Anatolievich.

Goals:

Educational – create conditions for independent study of the chemical properties of sulfuric acid, the industrial significance and use of sulfuric acid and its salts.

Developmental – to promote the development of skills to analyze the content of educational material, conduct a chemical experiment, and develop the skills to compose ionic and redox equations of chemical reactions.

Educational – promote the development of students’ cognitive activity, the ability to formulate and express their thoughts, and reason logically.

Tasks:

Educational : consider the physical and chemical properties (general and specific with other acids) of sulfuric acid, production, show the great importance of sulfuric acid and its salts in the national economy, draw students’ attention to the environmental problem associated with the production of sulfuric acid.

Educational : Continue to develop in students a dialectical-materialistic understanding of nature.

Developmental : Development of skills and abilities, working with a textbook and additional literature, rules for working on a desktop, the ability to systematize and generalize, establish cause-and-effect relationships, express one’s thoughts conclusively and competently, draw conclusions, draw diagrams, sketch.

Lesson type: Combined.

Equipment: Computer, projector, screen, presentation, PSHE named after. D. I. Mendeleev; table “Electrochemical series of voltages of metals”; alcohol lamps, test tubes, holders, chemical stand.

Reagents: H 2 SO 4 (dil. and conc.), indicators, copper, zinc, sodium hydroxide (solution), sodium carbonate, barium chloride, sugarC 12 H 22 O 11 .

Forms and methods of work in the lesson: frontal, explanatory - illustrative, visual, ICT.

DURING THE CLASSES

1. Organizational moment

2. Updating students' knowledge. In the last lesson we studied sulfur(IV) oxide and sulfurous acid, their physical and chemical properties.

Individual work using cards (2 students optional) :

Card 1
With which of the following substances, the formulas of which: H 2 O, BaO, CO 2 , can interact with sulfur oxide (4). Write down equations for chemical reactions.

Card 2
With which of the following substances, the formulas of which: Pb(NO 3 ) 2 , H 2 O, O 2 , CO 2 , hydrogen sulfide may interact. Write down equations for chemical reactions.

Frontal survey:

Where does hydrogen sulfide occur in nature?

What is the significance of hydrogen sulfide?

What physical properties does sulfur dioxide have?

What oxide is this, and what properties does it exhibit?

What salts does sulfurous acid form? Where are sulfur dioxide and sulfurous acid salts used?

What properties does sulfurous acid have?H 2 SO 3 ?

3. Learning new material: Sulfur (VI) oxide - SO 3 (sulfuric anhydride) (slide)

“And the Lord rained brimstone and fire upon Sodom and Gomorrah from the Lord out of heaven.

And he overthrew the cities, and all the surrounding areas, and all the inhabitants of the cities. And Abraham stood up... and looked towards Sodom and Gomorrah, and all the surrounding area, and saw: behold, smoke rises from the earth, like smoke from a furnace...” (Bible. Genesis 19:24-28). In 2000, British archaeologists established the exact location of these destroyed cities at the bottom of the Dead Sea. An interesting hypothesis of this disaster by the Greek geographer Strabo, based on his finds and research, which paints a terrifying picture: an earthquake, a fire, and then a rain of sulfuric acid. According to Strabo, these cities were destroyed.

Question for students: In your opinion, is it possible to confirm Strabo’s hypothesis from the point of view of the considered properties of sulfur(VI) oxide?Sulfur oxide or sulfuric anhydride, under normal conditions, is a colorless liquid, boiling at 44.6 * C, at 16.8 * C it solidifies into a transparent metallic mass. When heated above 50*C, the crystals ignite without melting. Extremely hygroscopic. Sulfuric anhydride very energetically, releasing a large amount of heat, reacts with water, forming sulfuric acid. When dissolvedSO 3 a large amount of heat is released in water, and if you add a large amount of heat to the waterSO 3 immediately, an explosion may occur.SO 3 soluble in conc. sulfuric acid, forming the so-called oleum. It has all the properties of acidic oxides: it reacts with basic oxides and bases.

Reacts with water to form sulfuric acid: (slide)

SO 3 +H 2 O=H 2 SO 4

Interacts with bases:

2KOH+ SO 3 =K 2 SO 4 + H 2 O; formed during the oxidation of sulfur dioxide: 2SO 2 + O 2= 2 SO 3 cat-r:t’, V 2 O 5 ;

4 . Motivation for cognitive activity:

Teacher:

“I will dissolve any metal.
The alchemist got me
In a simple clay retort.
I am known as the main acid...
When I myself dissolve in water,
I’m getting very hot..."

Teacher: What acid are we talking about?

Students: Sulfuric acid

I want to tell you a fairy tale about sulfuric acid. The tale is called “The Adventures of Sulfuric Acid.” (slide)

In one chemical kingdom, a baby was born to the Queen of Water and His Majesty Hexavalent Sulfur Oxide.

Everyone wanted a boy to be born - the heir to the throne. But as soon as the blue ribbon was tied to the baby, she immediately blushed. Everyone understood that a girl was born.

Experience 1. Add blue litmus to a flask with a solution of sulfuric acid. The color changed to red.

The girl was given a beautiful name - Acid, and her father's surname - Sulfuric. Let's remember its composition and structure.

Physical properties.

Teacher: Sulfuric acid is a colorless, heavy, non-volatile liquid, hygroscopic (water-removing). Therefore, it is used to dry gases. When it is dissolved in water, very strong heating occurs.Remember not to pour water into concentrated sulfuric acid!

– What is the rule for dissolving concentrated sulfuric acid?

Why is sulfuric acid diluted this way?

(sulfuric acid is almost 2 times heavier than water and heats up when dissolved).

Sulfuric acid is a strong electrolyte, but as a dibasic acid, dissociation occurs in steps.

Write the stepwise dissociation of sulfuric acid.

Thus, two types of salts are formed: medium and acidic.

Receipt. Sulfuric acid grew up and became interested in its many relatives. Together with her parents, she compiled a family tree - the entire family tree of the acid.

(slide)

Sulfur---→Sulfur(IV) oxide ---→Sulfur(VI) oxide ---→Sulfuric acid---→Sulfates
Oxygen---→Water---→Sulfuric acid---→Sulfates.

And Sulfuric Acid realized that in the future she would name her son, the heir to the throne, Sulfate.

Teacher: What can be used as a chemical. raw materials for the production of sulfuric acid? (sulfur, hydrogen sulfide, sulfur dioxide, sulfuric anhydride and metal sulfides).

Let's now take a closer lookphysical and chemical propertiessulfuric acid

Being in nature .

Teacher: Many people believe that sulfuric acid is only produced artificially.This is not true. Sulfuric acid and sulfur oxide(6) are found in some waters of volcanic origin.

Properties of sulfuric acid .

Teacher: Before finding out the chemical properties of sulfuric acid, let's remember the general properties of acids.

– What chemical properties do acids have? (with metals, oxides, bases, salts).

– What signs can be used to determine that a chemical reaction has occurred? (smell, color, gas, sediment).

How much time has passed since acid turned 18, but she just wanted to go on a trip. I wanted to see the world and show myself. She walked along the road for a long time and came to a fork. On the side of the road she saw a large stone on which was written: If you go to the right, you will come to acids, if you go to the left, you will come to salts, If you go straight, you will find your way. I thought about acid. How to find the right path? Let's help her.

We remember and follow safety rules.

Experience 2 Take two test tubes.

Place Zn in one test tube, place Cu in another test tube, and pour sulfuric acid solution into both test tubes.

What are you observing?

Write down the equations of chemical reactions in redox form.

Conclusion 1: Soluble sulfuric acid reacts with metals to produce hydrogen. Sulfur in sulfuric acid exhibits only oxidizing properties. Why? (since sulfur is in the highest oxidation state)

Task 3

Experience 3Pour NaOH solution into the test tube, then add phenolphthalein.

What are you observing?

Add sulfuric acid solution.

What are you observing?

Conclusion 3: Soluble sulfuric acid reacts with bases.

On his journey, Sulfuric Acid met two princes. One was called Sodium Carbonate, the other Barium Chloride. But sulfuric acid did not find a common language with the first prince - when approaching Sodium Carbonate, it disappeared, leaving behind only gas bubbles. And the second prince proposed to sulfuric acid and gave her a gorgeous white wedding dress.

Experience 4Take two test tubes.

Pour Na solution into one test tube 2 CO 3 , into another test tube BaCl solution 2 , pour a solution of sulfuric acid into both test tubes.

What are you observing?

Conclusion 4: Soluble sulfuric acid reacts with salts.

Conclusion 5: Dilute sulfuric acid has common properties characteristic of all acids.

Teacher: In addition, sulfuric acid has specific properties. Concentrated sulfuric acid is capable of splitting water from organic substances, charring them.

After the wedding, Sulfuric Acid and the groom went on a trip. The day was hot and they decided to relax and drink sweet tea. But as soon as the acid touched the sugar, I saw something strange.Experience 5. Sugar andconc.Sulfuric acid.

Barium Chloride and her fiancée Sulfuric Acid walked to a jewelry store to buy wedding rings. When the acid approached the display case, she immediately wanted to try on the jewelry. But when she put the copper and silver rings on her finger, they immediately dissolved. Only items made of gold and platinum remained unchanged. Why?(Students answer).

After some time, Sulfuric Acid and Barium Chloride gave birth to a wonderful baby, he had snow-white hair and named him Barium Sulfate. That’s the end of the fairy tale, and whoever listened – WELL DONE!

Application.

(Sulfuric acid remained in the city and brought many benefits.)

Teacher: Sulfuric acid is the most important product of the main chemical industry: the production of mineral fertilizers, metallurgy, and the refining of petroleum products. Its salts, for example copper sulfate, are used in agriculture to combat pests and plant diseases (work according to the textbook table).

1. Production of mineral fertilizers.
2. Purification of petroleum products.
3. Synthesis of dyes and drugs.
4. Production of acids and salts.
5. Drying of gases.
6. Metallurgy.

Fastening: Our consolidation will take place in the form of a game. Our class is divided into three teams, for each correct answer the team receives a token. Our 1st competition"warm-up"motto: “He who knows little knows a lot.” He who knows a lot, even this is not enough.”

1. What physical properties does sulfur have?acid? 2. How to distinguish sulfates from other salts? 3. Application of sulfurous acid.

4. Name its allotropic modifications of sulfur.
5. How do the two sulfur oxides differ in properties? 6. How are they obtained and where are they used?
7. Compare the structure and properties of ozone and oxygen.
8. How can you obtain sulfurous acid?
9. Why is it called “oil of vitriol”?
10. What salts does sulfurous acid form? « If nature gives good, then chemical reactions go on their own,” this is the motto of our next competition -"Transformers."Implement « chain» transformations. 1) Zn-> ZnSO4 ->Zn(OH)2 ->ZnSO4 ->BaSO4

2) S -> SO2 -> SO3 -> H2SO4 -> K2SO4

3)S->H2S->SO2->Na2SO3->BaSO3

3rd competition"Chemists and Khimichki"The motto of the competition is “One head is good, but two are better”

Graphic dictation : yes “+”, no “-”

1.Sulfur (IV) oxide is sulfur dioxide?

2. Sulfur (IV) oxide is a colorless gas with a pungent odor, heavier than air, poisonous?

3. Is sulfur oxide (IV) poorly soluble in water? -

4. Does sulfur dioxide have the properties of an acidic oxide? When it is dissolved in water, does sulfuric acid form?

5. SO 2 reacts with basic oxides?

6.SO 2 does it react with alkalis?

7. In sulfur oxide (IV)SO 2 oxidation state +2? -

8. Does sulfur dioxide exhibit the properties of an oxidizing agent and a reducing agent?

9. First aid for gas poisoning: hydrogen sulfide, sulfur dioxide: rinsing the nose and mouth with a 2% solution of sodium bicarbonateNaHCO 3 , peace, fresh air.

10. Does sulfurous acid dissociate stepwise?

11.H 2 SO 3 forms two series of salts: - medium (sulfites), - acidic (hydrosulfites)

Homework: § 21, p. 78, ex. No. 2, 3.

Sulfur is quite widespread in nature. Its content in the earth's crust is 0.0048 wt. %. A significant portion of sulfur occurs in the native state.

Sulfur is also found in the form of sulfides: pyrite, chalcopyrite and sulfates: gypsum, celestine and barite.

Many sulfur compounds are found in oil (thiophene C 4 H 4 S, organic sulfides) and petroleum gases (hydrogen sulfide).

Sulfur (VI) oxide (sulfuric anhydride, sulfur trioxide, sulfur gas) SO 3 - higher sulfur oxide, type of chemical bond: covalent

Spatial model of a molecule γ -SO 3

polar chemical bond. Under normal conditions, a highly volatile, colorless liquid with a suffocating odor. At temperatures below 16.9 °C it solidifies to form a mixture of various crystalline modifications of solid SO 3.

SO 3 molecules in the gas phase have a flat trigonal structure with D 3h symmetry (OSO angle = 120°, d(S-O) = 141 pm.) Upon transition to the liquid and crystalline states, a cyclic trimer and zigzag chains are formed.

Solid SO 3 exists in α-, β-, γ- and δ-forms, with melting points of 16.8, 32.5, 62.3 and 95 °C, respectively, and differing in crystal shape and degree of polymerization of SO 3. The α-form of SO 3 consists predominantly of trimer molecules. Other crystalline forms of sulfuric anhydride consist of zigzag chains: isolated in β-SO 3, connected in flat networks in γ-SO 3 or in spatial structures in δ-SO 3. When cooled, a colorless, ice-like, unstable α-form is initially formed from para, which gradually transforms in the presence of moisture into a stable β-form - white “silky” crystals similar to asbestos. The reverse transition of the β-form to the α-form is possible only through the gaseous state of SO 3. Both modifications “smoke” in air (droplets of H 2 SO 4 are formed) due to the high hygroscopicity of SO 3 . Mutual transition to other modifications proceeds very slowly. The variety of forms of sulfur trioxide is associated with the ability of SO 3 molecules to polymerize due to the formation of donor-acceptor bonds. The polymeric structures of SO 3 are easily converted into each other, and solid SO 3 usually consists of a mixture of different forms, the relative content of which depends on the conditions for obtaining sulfuric anhydride.

Acid-base: SO 3 is a typical acid oxide, sulfuric acid anhydride. Its chemical activity is quite high. When reacting with water it forms sulfuric acid:

However, in this reaction, sulfuric acid is formed in the form of an aerosol, and therefore, in industry, sulfur(VI) oxide is dissolved in sulfuric acid to form oleum, which is then dissolved in water to form sulfuric acid of the desired concentration.

Pollution of the biosphere with sulfur compounds

Sulfur dioxide so2 Atmospheric pollution with sulfur compounds has important environmental consequences. Mainly sulfur dioxide and hydrogen sulfide enter the atmosphere. Recently, other sulfur compounds formed as a result of microbiological processes have begun to attract attention. The main natural sources of sulfur dioxide are volcanic activity, as well as the oxidation of hydrogen sulfide and other sulfur compounds. According to some estimates, about 4 million tons of sulfur dioxide enter the atmosphere annually as a result of volcanic activity. But much more - about 200-215 million tons of sulfur dioxide - is formed from hydrogen sulfide, which enters the atmosphere during the decomposition of organic matter.

Industrial sources of sulfur dioxide have long surpassed volcanoes in intensity and are now equal to the total intensity of all natural sources. There are no fossil fuels in nature that consist solely of hydrocarbons. There is always an admixture of other elements, and one of them is sulfur. Even natural gas contains at least traces of sulfur. Crude oil contains from 0.1 to 5.5 percent sulfur, depending on the field, and coal contains from 0.2 to 7 percent sulfur. Therefore, fuel combustion produces 80-90 percent of all anthropogenic sulfur dioxide, with coal combustion producing the most (70 percent or more). The remaining 10-20 percent comes from the smelting of non-ferrous metals and the production of sulfuric acid. The raw materials for the production of copper, lead and zinc are mainly ores containing large amounts of sulfur (up to 45 percent). The same ores and other sulfur-rich minerals serve as raw materials for the production of sulfuric acid.

Sulfur dioxide is very poisonous, it poses a threat to the health and even life of humans and animals, and damages vegetation. In the USSR, for sulfur dioxide in the atmosphere, the maximum permissible concentrations (MAC) for a single exposure are 0.5 milligrams per cubic meter, the average per day is 0.05, which in terms of volumetric concentrations gives 0.17 and 0.017 ppm, respectively.

The usual concentration of sulfur dioxide in the lower atmosphere is 0.2 ppb. However, its distribution around the globe is very uneven. According to measurements at background observation (monitoring) stations located in different areas of the world and located at a distance from direct anthropogenic sources of this gas, concentrations differ by tens and hundreds of times. The highest concentrations are observed in the Northern Hemisphere, and they reach maximum values ​​in the eastern and central regions of the United States and Central Europe (10-14 micrograms per cubic meter, or 3.4-4.8 ppb). In areas where there are fewer large cities and industrial centers (western USA, European territory of the USSR, etc.), the concentration of sulfur dioxide is an order of magnitude lower (1-4 micrograms per cubic meter, or 0.34-1.37 ppb), and in some in cleaner areas, like the Caucasus and Lake Baikal, less than 0.1 micrograms per cubic meter, or 0.034 nb. In the Southern Hemisphere, the concentration of sulfur dioxide is 1.5-2 times lower than in the Northern Hemisphere, over the ocean it is significantly lower than over the continent, and over the ocean the concentration increases with altitude, while over the continents it decreases,

General characteristics of VA group elements.

Main subgroup of group V of the periodic system D.I. Mendeleev includes five elements: typical p-elements nitrogen N, phosphorus P, as well as similar elements of long periods arsenic As, antimony Sb, and bismuth Bi. They have a common name pnictogens. The atoms of these elements have 5 electrons at the outer level (configuration n s 2 n p 3).

In compounds, elements exhibit oxidation states from -3 to +5. The most typical degrees are +3 and +5. The oxidation state of +3 is more typical for bismuth.

When going from N to Bi, the atomic radius naturally increases. As atomic sizes increase, ionization energy decreases. This means that the connection of electrons of the outer energy level with the nucleus of atoms weakens, which leads to a weakening of non-metallic properties and an increase in metallic properties in the series from nitrogen to Bi.

Nitrogen and phosphorus are typical non-metals, i.e. acid formers. Arsenic has more pronounced non-metallic properties. Antimony exhibits nonmetallic and metallic properties to approximately the same extent. Bismuth is characterized by a predominance of metallic properties.

The nitrogen atom has three unpaired electrons. Therefore, the valency of nitrogen is three. Due to the absence of a d-sublevel at the outer level, its electrons cannot be separated. However, as a result of donor-acceptor interaction, nitrogen becomes tetravalent.

Phosphorus atoms and subsequent elements of the VA group have free orbitals at the d-sublevel and, when moving into an excited state, the 3s electrons will be separated. In the unexcited state, all elements of group 5A have a valency of 3, and in the excited state of all, except nitrogen, the valency is five.

Elements of this group form gaseous hydrogen compounds (hydrides) of the EN 3 type, in which their oxidation state is -3.

Since sulfur occurs in nature in a native state, it was known to man already in ancient times. Alchemists paid great attention to sulfur. Many of them already knew sulfuric acid. Vasily Valentin in the 15th century. described in detail its preparation (by heating iron sulfate). Sulfuric acid was produced industrially for the first time in England in the mid-18th century.

Being in nature, receiving:

Significant deposits of sulfur are often found in nature (mostly near volcanoes). The most common sulfides are: iron pyrite (pyrite) FeS 2, copper pyrite CuFeS 2, lead luster PbS and zinc blende ZnS. Sulfur is even more commonly found in the form of sulfates, such as calcium sulfate (gypsum and anhydrite), magnesium sulfate (bitter salt and kieserite), barium sulfate (heavy spar), strontium sulfate (celestine), sodium sulfate (Glauber's salt).
Receipt. 1. Smelting native sulfur from natural deposits, for example, using steam, and purifying raw sulfur by distillation.
2. Sulfur release during desulfurization of coal gasification products (water, air and lighting gases), for example, under the influence of air and activated carbon catalyst: 2H 2 S + O 2 = 2H 2 O + 2S
3. Release of sulfur during incomplete combustion of hydrogen sulfide (see equation above), upon acidification of sodium thiosulfate solution: Na 2 S 2 O 3 + 2HCI = 2NaCI + SO 2 + H 2 O + S
and when distilling a solution of ammonium polysulfide: (NH 4) 2 S 5 = (NH 4) 2 S + 4S

Physical properties:

Sulfur is a hard, brittle, yellow substance. It is practically insoluble in water, but dissolves well in carbon disulfide, aniline and some other solvents. Conducts heat and electricity poorly. Sulfur forms several allotropic modifications. ???...
...
At 444.6°C, sulfur boils, forming dark brown vapors.

Chemical properties:

The sulfur atom, having an incomplete external energy level, can attach two electrons and exhibit an oxidation state of -2. When electrons are given up or withdrawn to an atom of a more electronegative element, the oxidation state of sulfur can be +2, +4 and +6.
When sulfur burns in air or in oxygen, sulfur oxide (IV) SO 2 and partially sulfur oxide (VI) SO 3 are formed. When heated, it combines directly with hydrogen, halogens (except iodine), phosphorus, coal, and all metals except gold, platinum and iridium. For example:
S + H 2 = H 2 S; 3S + 2P = P 2 S 3 ; S + CI 2 = SCI 2 ; 2S + C = CS 2 ; S + Fe = FeS
As follows from the examples, in reactions with metals and some non-metals, sulfur is an oxidizing agent, and in reactions with more active non-metals, such as oxygen, chlorine, it is a reducing agent.
In relation to acids and alkalis...
...

The most important connections:

Sulfur dioxide, SO 2 is a colorless, heavy gas with a pungent odor, very easily soluble in water. In solution, SO 2 is easily oxidized.
Sulfurous acid, H 2 SO 3: dibasic acid, its salts are called sulfites. Sulfurous acid and its salts are strong reducing agents.
Sulfur trioxide, SO 3: colorless liquid, very strongly absorbs moisture forming sulfuric acid. Has the properties of acid oxides.
Sulfuric acid, H 2 SO 4: a very strong dibasic acid, even with moderate dilution, almost completely dissociates into ions. Sulfuric acid is low-volatile and displaces many other acids from their salts. The resulting salts are called sulfates, crystal hydrates are called vitriol. (for example, copper sulfate CuSO 4 * 5H 2 O, forms blue crystals).
Hydrogen sulfide, H 2 S: colorless gas with the smell of rotten eggs, boiling point = - 61°C. One of the weakest acids. Salts - sulfides
...
...
...

Application:

Sulfur is widely used in industry and agriculture. About half of its production is used to produce sulfuric acid. Sulfur is used to vulcanize rubber. In the form of sulfur color (fine powder), sulfur is used to combat diseases of vineyards and cotton. It is used to produce gunpowder, matches, and luminous compounds. In medicine, sulfur ointments are prepared to treat skin diseases.

Myakisheva E.A.
HF Tyumen State University, 561 gr.

Sources:
1. Chemistry: Reference. Ed./V. Schröter. – M.: Chemistry, 1989.
2. G. Remy “Course of inorganic chemistry” - M.: Chemistry, 1972.