Lesson objectives: students should know the structure, physical and chemical properties of H 2 SO 4; be able, based on knowledge of the rate of chemical reactions and chemical equilibrium, to justify the choice of conditions for the course of reactions that underlie the production of sulfuric acid; determine in practice sulfate and sulfide ions.

Basic concepts: sulfurous anhydride, sulfuric anhydride, complex use of raw materials.

During the classes

I. Organizational moment; homework check

II. new material

1. Electronic and structural formulas. Since sulfur is in the 3rd period of the periodic system, the octet rule is not respected and a sulfur atom can acquire up to twelve electrons.

(The six electrons of sulfur are indicated by an asterisk.)

2. Receipt. Sulfuric acid is formed by the interaction of sulfur oxide (VI) with water (SO 3 + H 2 O H 2 SO 4). A description of the production of sulfuric acid is given in § 16 (, pp. 37 - 42).

3. Physical properties. Sulfuric acid is a colorless, heavy (= 1.84 g / cm 3), non-volatile liquid. When dissolved in water, a very strong heating occurs. Remember not to pour water into concentrated sulfuric acid (Fig. 2)! Concentrated sulfuric acid absorbs water vapor from the air. This can be seen if an open vessel with concentrated sulfuric acid is balanced on a scale: after a while, the cup with the vessel will sink.

Rice. 2.

4. Chemical properties. Dilute sulfuric acid has general properties characteristic of acids and specific (Table 7).

Table 7

Chemical properties of sulfuric acid
Common with other acids	Specific
1. An aqueous solution changes the color of the indicators.	1. Concentrated sulfuric acid is a strong oxidizing agent: when heated, it reacts with almost all metals (except Au, Pt, and some others). In these reactions, depending on the activity of the metal and the conditions, SO2, H2S, S are released, for example: Cu + 2H 2 SO 4 CuSO 4 + SO 2 + 2H 2 O
2. Dilute sulfuric acid reacts with metals: H 2 SO 4 + Zn ZnSO 4 + H 2 2H + + SO 4 2- +Zn 0 Zn 2+ + SO 4 2- +H 2 0 2H + + Zn 0 Zn 2+ + H 2 0	2. Concentrated sulfuric acid reacts vigorously with water to form hydrates: H 2 SO 4 + nH 2 O H 2 SO 4 nH 2 O + Q Concentrated sulfuric acid is able to split off hydrogen and oxygen in the form of water from organic substances, charring organic substances.
3. Reacts with basic and amphoteric oxides: H 2 SO 4 + MgO MgSO 4 + H 2 O 2H + +SO 4 2- +MgOMg 2+ +SO 4 2- +H 2 O 2H + + MgO Mg 2+ + H 2 O	3. A characteristic reaction to sulfuric acid and its salts is the interaction with soluble barium salts: H 2 SO 4 + BaCl 2 BaSO 4 + 2HCl 2H + + SO 4 2- + Ba 2+ + 2Cl - BaSO 4 + 2H + + 2Cl - Ba 2+ + SO 4 2- BaSO 4 A white precipitate is formed, which is insoluble in either water or concentrated nitric acid.
4. Interacts with bases: H 2 SO 4 + 2KOH K 2 SO 4 + 2H 2 O 2H + + SO 4 2- + 2K + + 2OH - 2K + + SO 4 2- + 2H 2 O 2H + + 2OH - 2H 2 O If the acid is taken in excess, then an acid salt is formed: H 2 SO 4 + NaOH NaHSO 4 + H 2 O
5. Reacts with salts, displacing other acids from them: 3H 2 SO 4 + Ca 3 (PO 4) 2 3CaSO 4 + 2H 3 PO 4

Application. Sulfuric acid is widely used (Fig. 3), it is the main product of the chemical industry.

Rice. 3. The use of sulfuric acid: 1 - obtaining dyes; 2 - mineral fertilizers; 3 - purification of petroleum products; 4 - electrolytic production of copper; 5 - electrolyte in batteries; 6 - obtaining explosives; 7 - dyes; 8 - artificial silk; 9 - glucose; 10 - salts; 11 - acids.

Sulfuric acid forms two series of salts - medium and acidic:

Na 2 SO 4 NaHSO 4

sodium sulfate sodium hydrogen sulfate

(medium salt) (acid salt)

Sulfuric acid salts are widely used, for example, Na 2 SO 4 10H 2 O - sodium sulfate crystalline hydrate (Glauber's salt) is used in the production of soda, glass, in medicine and veterinary medicine. CaSO 4 2H 2 O - calcium sulfate crystalline hydrate (natural gypsum) - is used to obtain semi-aqueous gypsum, which is necessary in construction, and in medicine - for applying plaster bandages. CuSO 4 5H 2 O - copper (II) sulfate crystalline hydrate (copper sulfate) - is used in the fight against plant pests.

III. Fixing new material

1. In winter, a vessel with concentrated sulfuric acid is sometimes placed between the window frames. What is the purpose of doing this, why can't the vessel be filled with acid to the top?

2. Concentrated sulfuric acid, when heated, reacts with mercury and silver, just as it reacts with copper. Write equations for these reactions and indicate the oxidizing agent and reducing agent.

3. How to recognize sulfides? Where are they applied?

4. Make up reaction equations that are practically feasible using the diagrams below:

Hg + H 2 SO 4 (conc)

MgCl 2 + H 2 SO 4 (conc.)

Na 2 SO 3 + H 2 SO 4

Al(OH) 3 + H 2 SO 4

When compiling reaction equations, indicate the conditions for their implementation. Where necessary, write equations in ionic and abbreviated ionic form.

5. Name the oxidizing agent in the reactions: a) dilute sulfuric acid with metals; b) concentrated sulfuric acid with metals.

6. What do you know about sulfurous acid?

7. Why is concentrated sulfuric acid a strong oxidizing agent? What are the special properties of concentrated sulfuric acid?

8. How does concentrated sulfuric acid interact with metals?

9. Where are sulfuric acid and its salts used?

1. What volume of oxygen will be required for combustion: a) 3.4 kg of hydrogen sulfide; b) 6500 m 3 hydrogen sulfide?

2. What is the mass of a solution containing 0.2 mass fractions of sulfuric acid, which is consumed in the reaction with 4.5 g of aluminum?

Laboratory experiments

VI. Recognition of sulfate ions in solution. Pour 1-2 ml of sodium sulfate solution into one test tube, the same amount of zinc sulfate into another, and dilute sulfuric acid solution into the third. Place a granule of zinc into each test tube, and then add a few drops of a solution of barium chloride or barium nitrate.

Tasks. 1. How can sulfuric acid be distinguished from its salts? 2. How to distinguish sulfates from other salts? Write the equations of the reactions you have done in molecular, ionic, and abbreviated ionic form.

IV. Homework

Acids are chemical compounds consisting of hydrogen atoms and acidic residues, for example, SO4, SO3, PO4, etc. They are inorganic and organic. The former include hydrochloric, phosphoric, sulfide, nitric, sulfuric acid. To the second - acetic, palmitic, formic, stearic, etc.

What is sulfuric acid

This acid consists of two hydrogen atoms and an acid residue SO4. It has the formula H2SO4.

Sulfuric acid, or, as it is also called, sulfate, refers to inorganic oxygen-containing dibasic acids. This substance is considered one of the most aggressive and chemically active. In most chemical reactions, it acts as an oxidizing agent. This acid can be used in concentrated or diluted form, in these two cases it has slightly different chemical properties.

Physical properties

Sulfuric acid under normal conditions has a liquid state, its boiling point is approximately 279.6 degrees Celsius, the freezing point when it turns into solid crystals is about -10 degrees for one hundred percent and about -20 for 95 percent.

Pure 100% sulphate acid is an odorless and colorless oily liquid substance, which has almost twice the density of water - 1840 kg / m3.

Chemical properties of sulfate acid

Sulfuric acid reacts with metals, their oxides, hydroxides and salts. Diluted with water in various proportions, it can behave differently, so let's take a closer look at the properties of a concentrated and weak solution of sulfuric acid separately.

concentrated sulfuric acid solution

A concentrated solution is considered to be a solution that contains from 90 percent sulfate acid. Such a solution of sulfuric acid is able to react even with inactive metals, as well as with non-metals, hydroxides, oxides, salts. The properties of such a solution of sulfate acid are similar to those of concentrated nitrate acid.

Interaction with metals

During the chemical reaction of a concentrated solution of sulfate acid with metals located to the right of hydrogen in the electrochemical series of metal voltages (that is, with not the most active), the following substances are formed: sulfate of the metal with which the interaction takes place, water and sulfur dioxide. The metals, as a result of interaction with which the listed substances are formed, include copper (cuprum), mercury, bismuth, silver (argentum), platinum and gold (aurum).

Interaction with inactive metals

With metals that are to the left of hydrogen in the voltage series, concentrated sulfuric acid behaves a little differently. As a result of such a chemical reaction, the following substances are formed: sulfate of a certain metal, hydrogen sulfide or pure sulfur and water. The metals with which such a reaction takes place also include iron (ferum), magnesium, manganese, beryllium, lithium, barium, calcium and all the others that are in the series of voltages to the left of hydrogen, except for aluminum, chromium, nickel and titanium - with them concentrated sulfate acid does not react.

Interaction with non-metals

This substance is a strong oxidizing agent, therefore it is able to participate in redox chemical reactions with non-metals, such as, for example, carbon (carbon) and sulfur. As a result of such reactions, water is necessarily released. When this substance is added to carbon, carbon dioxide and sulfur dioxide are also released. And if you add acid to sulfur, you get only sulfur dioxide and water. In such a chemical reaction, sulfate acid plays the role of an oxidizing agent.

Interaction with organic substances

Carbonization can be distinguished among the reactions of sulfuric acid with organic substances. Such a process occurs when a given substance collides with paper, sugar, fibers, wood, etc. In this case, carbon is released in any case. The carbon formed during the reaction can partially interact with sulfuric acid in excess. The photo shows the reaction of sugar with a solution of sulfate acid of medium concentration.

Reactions with salts

Also, a concentrated solution of H2SO4 reacts with dry salts. In this case, a standard exchange reaction occurs, in which metal sulfate is formed, which was present in the structure of the salt, and an acid with a residue that was in the composition of the salt. However, concentrated sulfuric acid does not react with salt solutions.

Interaction with other substances

Also, this substance can react with metal oxides and their hydroxides, in these cases exchange reactions occur, in the first metal sulfate and water are released, in the second - the same.

Chemical properties of a weak solution of sulfate acid

Dilute sulfuric acid reacts with many substances and has the same properties as all acids. It, unlike concentrated, interacts only with active metals, that is, those that are to the left of hydrogen in a series of voltages. In this case, the same substitution reaction occurs, as in the case of any acid. This releases hydrogen. Also, such an acid solution interacts with salt solutions, as a result of which an exchange reaction occurs, already discussed above, with oxides - just like concentrated, with hydroxides - also the same. In addition to ordinary sulfates, there are also hydrosulfates, which are the product of the interaction of hydroxide and sulfuric acid.

How to know if a solution contains sulfuric acid or sulfates

To determine whether these substances are present in a solution, a special qualitative reaction for sulfate ions is used, which allows you to find out. It consists in adding barium or its compounds to the solution. As a result, a white precipitate (barium sulfate) may form, indicating the presence of sulfates or sulfuric acid.

How is sulfuric acid produced?

The most common method of industrial production of this substance is its extraction from iron pyrite. This process occurs in three stages, each of which occurs a certain chemical reaction. Let's consider them. First, oxygen is added to pyrite, resulting in the formation of ferum oxide and sulfur dioxide, which is used for further reactions. This interaction occurs at high temperature. This is followed by a step in which, by adding oxygen in the presence of a catalyst, which is vanadium oxide, sulfur trioxide is obtained. Now, at the last stage, water is added to the resulting substance, and sulfate acid is obtained. This is the most common process for the industrial extraction of sulfate acid, it is used most often because pyrite is the most accessible raw material suitable for the synthesis of the substance described in this article. Sulfuric acid obtained using such a process is used in various industries - both in the chemical industry and in many others, for example, in oil refining, ore dressing, etc. It is also often used in the manufacturing technology of many synthetic fibers .

New topic: Sulfuric acid - H 2 SO 4

1. Electronic and structural formulas of sulfuric acid

*S - sulfur is in an excited state 1S 2 2S 2 2P 6 3S 1 3P 3 3d 2

The electronic formula of the sulfuric acid molecule:

H-O-O

\\ //

// \\

H-O-O

Structural formula of the sulfuric acid molecule:

1 H - -2 O -2 O

\\ //

// \\

1 H - -2 O -2 O

2. Receipt:

The chemical processes for the production of sulfuric acid can be represented as the following scheme:

S + O 2 + O 2 + H 2 O

FeS 2 SO 2 SO 3 H 2 SO 4

H 2 S

Sulfuric acid is produced in three stages:

1 stage. Sulfur, iron pyrite or hydrogen sulfide are used as raw materials.

4 FeS 2 + 11 O 2 \u003d 2Fe 2 O 3 + 8SO 2

2 stage. Oxidation of SO 2 to SO 3 oxygen with catalyst V 2 O 5

V 2 O 5

2SO 2 + O 2 \u003d 2SO 3 + Q

3rd stage. To turn SO 3 not water is used in sulfuric acids. there is a strong heating, and a concentrated solution of sulfuric acid.

SO 3 + H 2 O H 2 SO 4

The result is oleum - a solution of SO 3 in sulfuric acid.

Apparatus circuit diagram(see textbook p.105)

3.Physical properties.

a) liquid b) colorless c) heavy (vitriol) d) non-volatile

d) when dissolved in water, strong heating occurs (Therefore, sulfuric acid must certainly be poured into water, and not vice versa!)

4. Chemical properties of Sulfuric acid.

Diluted H 2 SO 4	Concentrated H 2 SO 4
Has all the properties of acids	Has specific properties
1.Changes the color of the indicator: H 2 SO 4 H + + HSO 4 - HSO 4 - H + + SO 4 2- 2.Reacts with metals standing up to hydrogen: Zn + H 2 SO 4 ZnSO 4 + H 2 3. Reacts with basic and amphoteric oxides: MgO + H 2 SO 4 MgSO 4 +H 2 O 4. Interacts with bases (neutralization reaction) 2NaOH + H 2 SO 4 Na 2 SO 4 + 2H 2 O excess acid forms acidic salts NaOH + H 2 SO 4 NaHSO 4 +H 2 O 5. Reacts with dry salts, displacing other acids from them (this is the strongest and non-volatile acid): 2NaCl+H 2 SO 4 Na 2 SO 4 +2HCl 6. Reacts with salt solutions if an insoluble salt is formed: BaCl 2 + H 2 SO 4 BaSO 4 + 2HCl - white precipitate qualitative reaction to the SO ion 4 2- 7. When heated, it decomposes: H 2 SO 4 H 2 O + SO 3	1.Concentrated H 2 SO 4 - the strongest oxidizing agent, when heated, it reacts with all metals (except Au and Pt). In these reactions, depending on the activity of the metal and the conditions, S,SO 2 or H 2 S For example: 0 +6 +2 +4 Cu+ conc 2H 2 SO 4 CuSO 4 +SO 2 +H 2 O 2.conc. H2SO4 passivates iron and aluminium, therefore it can be transported in steel and aluminum tanks. 3. conc. H2SO4 absorbs water well H 2 SO 4 + H 2 O H 2 SO 4 * 2H 2 O Therefore, it chars organic matter

5.Application : Sulfuric acid is one of the most important products used in various industries. Its main consumers are the production of mineral fertilizers, metallurgy, and refining of petroleum products. Sulfuric acid is used in the manufacture of other acids, detergents, explosives, medicines, paints, and as electrolytes for lead-acid batteries. (Textbook p.103).

6.Salts of sulfuric acid

Sulfuric acid dissociates in steps

H 2 SO 4 H + + HSO 4 -

HSO 4 - H + + SO 4 2-

therefore, it forms two types of salts - sulfates and hydrosulfates

For example: Na 2 SO 4 - sodium sulfate (medium salt)

NaHSO4 - sodium hydrosulfate (acid salt)

The most widely used are:

Na 2 SO 4 * 10H 2 O - Glauber's salt (used in the production of soda, glass, medicine and

Veterinarians.

CaSO 4 * 2H 2 O - gypsum

СuSO 4 *5H 2 O - copper sulfate (used in agriculture).

Laboratory experience

Chemical properties of sulfuric acid.

Equipment : Test tubes.

Reagents: sulfuric acid, methyl orange, zinc, magnesium oxide, sodium hydroxide and phenolphthalein, sodium carbonate, barium chloride.

b) Fill in the table of observations

Sulfuric acid (H2SO4) is one of the most corrosive and dangerous chemicals known to man, especially in concentrated form. Chemically pure sulfuric acid is a heavy toxic liquid of oily consistency, odorless and colorless. It is obtained by the oxidation of sulfur dioxide (SO2) by the contact method.

At a temperature of + 10.5 °C, sulfuric acid turns into a frozen glassy crystalline mass, greedily, like a sponge, absorbing moisture from the environment. In industry and chemistry, sulfuric acid is one of the main chemical compounds and occupies a leading position in terms of production in tons. That is why sulfuric acid is called the "blood of chemistry". With the help of sulfuric acid, fertilizers, medicines, other acids, large fertilizers, and much more are obtained.

Basic physical and chemical properties of sulfuric acid

1. Sulfuric acid in its pure form (formula H2SO4), at a concentration of 100%, is a colorless thick liquid. The most important property of H2SO4 is its high hygroscopicity - the ability to remove water from the air. This process is accompanied by a massive release of heat.
2. H2SO4 is a strong acid.
3. Sulfuric acid is called monohydrate - it contains 1 mol of H2O (water) per 1 mol of SO3. Because of its impressive hygroscopic properties, it is used to extract moisture from gases.
4. Boiling point - 330 ° C. In this case, the acid is decomposed into SO3 and water. Density - 1.84. Melting point - 10.3 ° C /.
5. Concentrated sulfuric acid is a powerful oxidizing agent. To start the redox reaction, the acid must be heated. The result of the reaction is SO2. S+2H2SO4=3SO2+2H2O
6. Depending on the concentration, sulfuric acid reacts differently with metals. In a dilute state, sulfuric acid is capable of oxidizing all metals that are in the series of voltages to hydrogen. An exception is made as the most resistant to oxidation. Dilute sulfuric acid reacts with salts, bases, amphoteric and basic oxides. Concentrated sulfuric acid is capable of oxidizing all metals in the series of voltages, and silver too.
7. Sulfuric acid forms two types of salts: acidic (hydrosulfates) and medium (sulfates)
8. H2SO4 enters into an active reaction with organic substances and non-metals, and it can turn some of them into coal.
9. Sulfuric anhydrite is perfectly soluble in H2SO4, and in this case oleum is formed - a solution of SO3 in sulfuric acid. Outwardly, it looks like this: fuming sulfuric acid, releasing sulfuric anhydrite.
10. Sulfuric acid in aqueous solutions is a strong dibasic acid, and when it is added to water, a huge amount of heat is released. When preparing dilute solutions of H2SO4 from concentrated ones, it is necessary to add a heavier acid to water in a small stream, and not vice versa. This is done to avoid boiling water and splashing acid.

Concentrated and dilute sulfuric acids

Concentrated solutions of sulfuric acid include solutions from 40%, capable of dissolving silver or palladium.

Dilute sulfuric acid includes solutions whose concentration is less than 40%. These are not such active solutions, but they are able to react with brass and copper.

Getting sulfuric acid

The production of sulfuric acid on an industrial scale was launched in the 15th century, but at that time it was called "vitriol". If earlier humanity consumed only a few tens of liters of sulfuric acid, then in the modern world the calculation goes to millions of tons per year.

The production of sulfuric acid is carried out industrially, and there are three of them:

1. contact method.
2. nitrous method
3. Other Methods

Let's talk in detail about each of them.

contact production method

The contact method of production is the most common, and it performs the following tasks:

• It turns out a product that satisfies the needs of the maximum number of consumers.
• During production, harm to the environment is reduced.

In the contact method, the following substances are used as raw materials:

• pyrite (sulfur pyrites);
• sulfur;
• vanadium oxide (this substance causes the role of a catalyst);
• hydrogen sulfide;
• sulfides of various metals.

Before starting the production process, raw materials are pre-prepared. To begin with, pyrite is subjected to grinding in special crushing plants, which allows, due to an increase in the area of ​​​​contact of the active substances, to accelerate the reaction. Pyrite undergoes purification: it is lowered into large containers of water, during which waste rock and all kinds of impurities float to the surface. They are removed at the end of the process.

The production part is divided into several stages:

1. After crushing, pyrite is cleaned and sent to the furnace - where it is fired at temperatures up to 800 ° C. According to the principle of counterflow, air is supplied to the chamber from below, and this ensures that the pyrite is in a suspended state. Today, this process takes a few seconds, but earlier it took several hours to fire. During the roasting process, wastes appear in the form of iron oxide, which are removed and subsequently transferred to the enterprises of the metallurgical industry. During firing, water vapor, O2 and SO2 gases are released. When the purification from water vapor and the smallest impurities is completed, pure sulfur oxide and oxygen are obtained.
2. In the second stage, an exothermic reaction takes place under pressure using a vanadium catalyst. The start of the reaction starts when the temperature reaches 420 °C, but it can be increased to 550 °C in order to increase efficiency. During the reaction, catalytic oxidation occurs and SO2 becomes SO3.
3. The essence of the third stage of production is as follows: the absorption of SO3 in the absorption tower, during which the oleum H2SO4 is formed. In this form, H2SO4 is poured into special containers (it does not react with steel) and is ready to meet the end user.

During production, as we said above, a lot of thermal energy is generated, which is used for heating purposes. Many sulfuric acid plants install steam turbines that use the exhaust steam to generate additional electricity.

Nitrous process for the production of sulfuric acid

Despite the advantages of the contact method of production, which produces more concentrated and pure sulfuric acid and oleum, quite a lot of H2SO4 is produced by the nitrous method. In particular, at superphosphate plants.

For the production of H2SO4, sulfur dioxide acts as the initial substance, both in the contact and in the nitrous method. It is obtained specifically for these purposes by burning sulfur or roasting sulfurous metals.

The conversion of sulfur dioxide into sulfurous acid consists in the oxidation of sulfur dioxide and the addition of water. The formula looks like this:
SO2 + 1|2 O2 + H2O = H2SO4

But sulfur dioxide does not directly react with oxygen, therefore, with the nitrous method, the oxidation of sulfur dioxide is carried out using nitrogen oxides. Higher oxides of nitrogen (we are talking about nitrogen dioxide NO2, nitrogen trioxide NO3) in this process are reduced to nitric oxide NO, which is subsequently again oxidized by oxygen to higher oxides.

The production of sulfuric acid by the nitrous method is technically formalized in the form of two methods:

• Chamber.
• Tower.

The nitrous method has a number of advantages and disadvantages.

Disadvantages of the nitrous method:

• It turns out 75% sulfuric acid.
• Product quality is low.
• Incomplete return of nitrogen oxides (addition of HNO3). Their emissions are harmful.
• The acid contains iron, nitrogen oxides and other impurities.

Advantages of the nitrous method:

• The cost of the process is lower.
• The possibility of processing SO2 at 100%.
• Simplicity of hardware design.

Major Russian Sulfuric Acid Plants

The annual production of H2SO4 in our country is in the six-digit figures - about 10 million tons. The leading producers of sulfuric acid in Russia are companies that are, in addition, its main consumers. We are talking about companies whose field of activity is the production of mineral fertilizers. For example, "Balakovo mineral fertilizers", "Ammophos".

Crimean Titan, the largest producer of titanium dioxide in Eastern Europe, operates in Armyansk, Crimea. In addition, the plant is engaged in the production of sulfuric acid, mineral fertilizers, iron sulphate, etc.

Sulfuric acid of various types is produced by many factories. For example, battery sulfuric acid is produced by: Karabashmed, FKP Biysk Oleum Plant, Svyatogor, Slavia, Severkhimprom, etc.

Oleum is produced by UCC Shchekinoazot, FKP Biysk Oleum Plant, Ural Mining and Metallurgical Company, Kirishinefteorgsintez Production Association, etc.

Sulfuric acid of high purity is produced by UCC Shchekinoazot, Component-Reaktiv.

Spent sulfuric acid can be bought at the plants ZSS, HaloPolymer Kirovo-Chepetsk.

Manufacturers of technical sulfuric acid are Promsintez, Khiprom, Svyatogor, Apatit, Karabashmed, Slavia, Lukoil-Permnefteorgsintez, Chelyabinsk Zinc Plant, Electrozinc, etc.

Due to the fact that pyrite is the main raw material in the production of H2SO4, and this is a waste product of enrichment enterprises, its suppliers are the Norilsk and Talnakh enrichment plants.

The leading world positions in the production of H2SO4 are occupied by the USA and China, which account for 30 million tons and 60 million tons, respectively.

Scope of sulfuric acid

About 200 million tons of H2SO4 are consumed annually in the world, from which a wide range of products is produced. Sulfuric acid rightfully holds the palm among other acids in terms of industrial use.

As you already know, sulfuric acid is one of the most important products of the chemical industry, so the scope of sulfuric acid is quite wide. The main uses of H2SO4 are as follows:

• Sulfuric acid is used in huge volumes for the production of mineral fertilizers, and it takes about 40% of the total tonnage. For this reason, plants producing H2SO4 are being built next to fertilizer plants. These are ammonium sulfate, superphosphate, etc. In their production, sulfuric acid is taken in its pure form (100% concentration). It will take 600 liters of H2SO4 to produce a ton of ammophos or superphosphate. These fertilizers are mostly used in agriculture.
• H2SO4 is used to make explosives.
• Purification of petroleum products. To obtain kerosene, gasoline, mineral oils, hydrocarbon purification is required, which occurs with the use of sulfuric acid. In the process of refining oil for the purification of hydrocarbons, this industry "takes" as much as 30% of the world's tonnage of H2SO4. In addition, the octane number of fuel is increased with sulfuric acid and wells are treated during oil production.
• in the metallurgical industry. Sulfuric acid is used in metallurgy to remove scale and rust from wire, sheet metal, as well as to reduce aluminum in the production of non-ferrous metals. Before coating metal surfaces with copper, chromium or nickel, the surface is etched with sulfuric acid.
• In the manufacture of medicines.
• in the production of paints.
• in the chemical industry. H2SO4 is used in the production of detergents, ethyl detergent, insecticides, etc., and these processes are impossible without it.
• To obtain other known acids, organic and inorganic compounds used for industrial purposes.

Sulfuric acid salts and their uses

The most important salts of sulfuric acid are:

• Glauber's salt Na2SO4 10H2O (crystalline sodium sulfate). The scope of its application is quite capacious: the production of glass, soda, in veterinary medicine and medicine.
• Barium sulfate BaSO4 is used in the production of rubber, paper, white mineral paint. In addition, it is indispensable in medicine for fluoroscopy of the stomach. It is used to make "barium porridge" for this procedure.
• Calcium sulfate CaSO4. In nature, it can be found in the form of gypsum CaSO4 2H2O and anhydrite CaSO4. Gypsum CaSO4 2H2O and calcium sulfate are used in medicine and construction. With gypsum, when heated to a temperature of 150 - 170 ° C, partial dehydration occurs, as a result of which burnt gypsum, known to us as alabaster, is obtained. Kneading alabaster with water to the consistency of batter, the mass quickly hardens and turns into a kind of stone. It is this property of alabaster that is actively used in construction work: casts and molds are made from it. In plastering work, alabaster is indispensable as a binder. Patients of trauma departments are given special fixing solid bandages - they are made on the basis of alabaster.
• Ferrous vitriol FeSO4 7H2O is used for the preparation of ink, impregnation of wood, and also in agricultural activities for the destruction of pests.
• Alum KCr(SO4)2 12H2O, KAl(SO4)2 12H2O, etc. are used in the production of paints and the leather industry (tanning).
• Many of you know copper sulfate CuSO4 5H2O firsthand. It is an active assistant in agriculture in the fight against plant diseases and pests - an aqueous solution of CuSO4 5H2O is used to pickle grain and spray plants. It is also used to prepare some mineral paints. And in everyday life it is used to remove mold from the walls.
• Aluminum sulfate - it is used in the pulp and paper industry.

Sulfuric acid in dilute form is used as an electrolyte in lead-acid batteries. In addition, it is used to produce detergents and fertilizers. But in most cases, it comes in the form of oleum - this is a solution of SO3 in H2SO4 (other oleum formulas can also be found).

Amazing fact! Oleum is more reactive than concentrated sulfuric acid, but despite this, it does not react with steel! It is for this reason that it is easier to transport than sulfuric acid itself.

The sphere of use of the “queen of acids” is truly large-scale, and it is difficult to tell about all the ways in which it is used in industry. It is also used as an emulsifier in the food industry, for water treatment, in the synthesis of explosives, and for many other purposes.

History of sulfuric acid

Who among us has never heard of blue vitriol? So, it was studied in antiquity, and in some works of the beginning of a new era, scientists discussed the origin of vitriol and their properties. Vitriol was studied by the Greek physician Dioscorides, the Roman explorer of nature Pliny the Elder, and in their writings they wrote about the ongoing experiments. For medical purposes, various vitriol substances were used by the ancient healer Ibn Sina. How vitriol was used in metallurgy was mentioned in the works of the alchemists of Ancient Greece Zosima from Panopolis.

The first way to obtain sulfuric acid is the process of heating potassium alum, and there is information about this in the alchemical literature of the XIII century. At that time, the composition of alum and the essence of the process were not known to alchemists, but already in the 15th century, they began to engage in the chemical synthesis of sulfuric acid purposefully. The process was as follows: alchemists treated a mixture of sulfur and antimony (III) sulfide Sb2S3 by heating with nitric acid.

In medieval times in Europe, sulfuric acid was called "vitriol oil", but then the name changed to vitriol.

In the 17th century, Johann Glauber obtained sulfuric acid by burning potassium nitrate and native sulfur in the presence of water vapor. As a result of the oxidation of sulfur with nitrate, sulfur oxide was obtained, which reacted with water vapor, and as a result, an oily liquid was obtained. It was vitriol oil, and this name for sulfuric acid exists to this day.

The pharmacist from London, Ward Joshua, used this reaction for the industrial production of sulfuric acid in the thirties of the 18th century, but in the Middle Ages its consumption was limited to a few tens of kilograms. The scope of use was narrow: for alchemical experiments, purification of precious metals and in the pharmaceutical business. Concentrated sulfuric acid was used in small quantities in the manufacture of special matches that contained bertolet salt.

In Russia, vitriol appeared only in the 17th century.

In Birmingham, England, John Roebuck adapted the above method for producing sulfuric acid in 1746 and launched production. At the same time, he used strong large lead-lined chambers, which were cheaper than glass containers.

In industry, this method held positions for almost 200 years, and 65% sulfuric acid was obtained in the chambers.

After a while, the English Glover and the French chemist Gay-Lussac improved the process itself, and sulfuric acid began to be obtained with a concentration of 78%. But such an acid was not suitable for the production, for example, of dyes.

In the early 19th century, new methods were discovered for oxidizing sulfur dioxide to sulfuric anhydride.

Initially, this was done using nitrogen oxides, and then platinum was used as a catalyst. These two methods of oxidizing sulfur dioxide have further improved. The oxidation of sulfur dioxide on platinum and other catalysts became known as the contact method. And the oxidation of this gas with nitrogen oxides was called the nitrous method for producing sulfuric acid.

It was not until 1831 that the British acetic acid dealer Peregrine Philips patented an economical process for the production of sulfur oxide (VI) and concentrated sulfuric acid, and it is he who is today known to the world as a contact method for obtaining it.

The production of superphosphate began in 1864.

In the eighties of the nineteenth century in Europe, the production of sulfuric acid reached 1 million tons. The main producers were Germany and England, producing 72% of the total volume of sulfuric acid in the world.

Transportation of sulfuric acid is a labor-intensive and responsible undertaking.

Sulfuric acid belongs to the class of hazardous chemicals, and upon contact with the skin causes severe burns. In addition, it can cause chemical poisoning of a person. If certain rules are not followed during transportation, then sulfuric acid, due to its explosive nature, can cause a lot of harm to both people and the environment.

Sulfuric acid has been assigned a hazard class 8 and transportation must be carried out by specially trained and trained professionals. An important condition for the delivery of sulfuric acid is compliance with specially developed Rules for the transport of dangerous goods.

Transportation by road is carried out according to the following rules:

1. For transportation, special containers are made of a special steel alloy that does not react with sulfuric acid or titanium. Such containers do not oxidize. Hazardous sulfuric acid is transported in special sulfuric acid chemical tanks. They differ in design and are selected during transportation depending on the type of sulfuric acid.
2. When transporting fuming acid, specialized isothermal thermos tanks are taken, in which the necessary temperature regime is maintained to preserve the chemical properties of the acid.
3. If ordinary acid is being transported, then a sulfuric acid tank is selected.
4. Transportation of sulfuric acid by road, such as fuming, anhydrous, concentrated, for batteries, glover, is carried out in special containers: tanks, barrels, containers.
5. Transportation of dangerous goods can only be carried out by drivers who have an ADR certificate in their hands.
6. Travel time has no restrictions, since during transportation it is necessary to strictly adhere to the permissible speed.
7. During transportation, a special route is built, which should run, bypassing crowded places and production facilities.
8. Transport must have special markings and danger signs.

Dangerous properties of sulfuric acid for humans

Sulfuric acid poses an increased danger to the human body. Its toxic effect occurs not only by direct contact with the skin, but by inhalation of its vapors, when sulfur dioxide is released. The hazard applies to:

• respiratory system;
• Integuments;
• Mucous membranes.

Intoxication of the body can be enhanced by arsenic, which is often part of sulfuric acid.

Important! As you know, when acid comes into contact with the skin, severe burns occur. No less dangerous is poisoning with sulfuric acid vapors. A safe dose of sulfuric acid in the air is only 0.3 mg per 1 square meter.

If sulfuric acid gets on the mucous membranes or on the skin, a severe burn appears, which does not heal well. If the burn is impressive in scale, the victim develops a burn disease, which can even lead to death if qualified medical care is not provided in a timely manner.

Important! For an adult, the lethal dose of sulfuric acid is only 0.18 cm per 1 liter.

Of course, it is problematic to “experience for yourself” the toxic effect of acid in ordinary life. Most often, acid poisoning occurs due to neglect of industrial safety when working with a solution.

Mass poisoning with sulfuric acid vapor can occur due to technical problems in production or negligence, and a massive release into the atmosphere occurs. To prevent such situations, special services are working, the task of which is to control the functioning of production where hazardous acid is used.

What are the symptoms of sulfuric acid intoxication?

If the acid was ingested:

• Pain in the region of the digestive organs.
• Nausea and vomiting.
• Violation of the stool, as a result of severe intestinal disorders.
• Strong secretion of saliva.
• Due to the toxic effects on the kidneys, the urine becomes reddish.
• Swelling of the larynx and throat. There are wheezing, hoarseness. This can lead to death from suffocation.
• Brown spots appear on the gums.
• The skin turns blue.

With a burn of the skin, there can be all the complications inherent in a burn disease.

When poisoning in pairs, the following picture is observed:

• Burn of the mucous membrane of the eyes.
• Nose bleed.
• Burns of the mucous membranes of the respiratory tract. In this case, the victim experiences a strong pain symptom.
• Swelling of the larynx with symptoms of suffocation (lack of oxygen, skin turns blue).
• If the poisoning is severe, then there may be nausea and vomiting.

It's important to know! Acid poisoning after ingestion is much more dangerous than intoxication from inhalation of vapors.

First aid and therapeutic procedures for damage by sulfuric acid

Proceed as follows when in contact with sulfuric acid:

• Call an ambulance first. If the liquid got inside, then do a gastric lavage with warm water. After that, in small sips you will need to drink 100 grams of sunflower or olive oil. In addition, you should swallow a piece of ice, drink milk or burnt magnesia. This must be done to reduce the concentration of sulfuric acid and alleviate the human condition.
• If acid gets into the eyes, rinse them with running water, and then drip with a solution of dicaine and novocaine.
• If acid gets on the skin, the burned area should be washed well under running water and bandaged with soda. Rinse for about 10-15 minutes.
• In case of vapor poisoning, you need to go out into fresh air, and also rinse the affected mucous membranes with water as far as possible.

In a hospital setting, treatment will depend on the area of ​​the burn and the degree of poisoning. Anesthesia is carried out only with novocaine. In order to avoid the development of an infection in the affected area, a course of antibiotic therapy is selected for the patient.

In gastric bleeding, plasma is injected or blood is transfused. The source of bleeding can be removed surgically.

1. Sulfuric acid in its pure 100% form is found in nature. For example, in Italy, Sicily in the Dead Sea, you can see a unique phenomenon - sulfuric acid seeps right from the bottom! And here's what happens: pyrite from the earth's crust serves in this case as a raw material for its formation. This place is also called the Lake of Death, and even insects are afraid to fly up to it!
2. After large volcanic eruptions, droplets of sulfuric acid can often be found in the earth's atmosphere, and in such cases, the "culprit" can bring negative consequences for the environment and cause serious climate change.
3. Sulfuric acid is an active water absorber, so it is used as a gas dryer. In the old days, in order to prevent windows from fogging up in the rooms, this acid was poured into jars and placed between the panes of window openings.
4. Sulfuric acid is the main cause of acid rain. The main cause of acid rain is air pollution with sulfur dioxide, and when dissolved in water, it forms sulfuric acid. In turn, sulfur dioxide is emitted when fossil fuels are burned. In the acid rains studied in recent years, the content of nitric acid has increased. The reason for this phenomenon is the reduction of sulfur dioxide emissions. Despite this fact, sulfuric acid remains the main cause of acid rain.

We offer you a video selection of interesting experiments with sulfuric acid.

Consider the reaction of sulfuric acid when it is poured into sugar. In the first seconds of sulfuric acid entering the flask with sugar, the mixture darkens. After a few seconds, the substance turns black. The most interesting thing happens next. The mass begins to grow rapidly and climb out of the flask. At the output, we get a proud substance, similar to porous charcoal, exceeding the original volume by 3-4 times.

The author of the video suggests comparing the reaction of Coca-Cola with hydrochloric acid and sulfuric acid. When mixing Coca-Cola with hydrochloric acid, no visual changes are observed, but when mixed with sulfuric acid, Coca-Cola begins to boil.

An interesting interaction can be observed when sulfuric acid gets on toilet paper. Toilet paper is made from cellulose. When acid enters, cellulose molecules instantly break down with the release of free carbon. Similar charring can be observed when acid gets on the wood.

I add a small piece of potassium to a flask with concentrated acid. In the first second, smoke is released, after which the metal instantly flares up, lights up and explodes, cutting into pieces.

In the next experiment, when sulfuric acid hits a match, it flares up. In the second part of the experiment, aluminum foil is immersed with acetone and a match inside. There is an instantaneous heating of the foil with the release of a huge amount of smoke and its complete dissolution.

An interesting effect is observed when baking soda is added to sulfuric acid. Soda instantly turns yellow. The reaction proceeds with rapid boiling and an increase in volume.

We categorically do not advise to carry out all the above experiments at home. Sulfuric acid is a very corrosive and toxic substance. Such experiments must be carried out in special rooms that are equipped with forced ventilation. The gases released in reactions with sulfuric acid are highly toxic and can cause damage to the respiratory tract and poison the body. In addition, such experiments are carried out in personal protective equipment for the skin and respiratory organs. Take care of yourself!

Any acid is a complex substance, the molecule of which contains one or more hydrogen atoms and an acid residue.

The formula of sulfuric acid is H2SO4. Therefore, the composition of the sulfuric acid molecule includes two hydrogen atoms and the acid residue SO4.

Sulfuric acid is formed when sulfur oxide reacts with water

SO3+H2O -> H2SO4

Pure 100% sulfuric acid (monohydrate) is a heavy liquid, viscous like oil, colorless and odorless, with a sour "copper" taste. Already at a temperature of +10 ° C, it solidifies and turns into a crystalline mass.

Concentrated sulfuric acid contains approximately 95% H2SO4. And it freezes at temperatures below -20 ° C.

Interaction with water

Sulfuric acid is highly soluble in water, mixing with it in any ratio. This releases a large amount of heat.

Sulfuric acid is able to absorb water vapor from the air. This property is used in industry for drying gases. Gases are dried by passing them through special containers with sulfuric acid. Of course, this method can only be used for those gases that do not react with it.

It is known that when sulfuric acid comes into contact with many organic substances, especially carbohydrates, these substances are charred. The fact is that carbohydrates, like water, contain both hydrogen and oxygen. Sulfuric acid robs them of these elements. What remains is coal.

In an aqueous solution of H2SO4, the indicators litmus and methyl orange turn red, which indicates that this solution has a sour taste.

Interaction with metals

Like any other acid, sulfuric acid is capable of replacing hydrogen atoms with metal atoms in its molecule. It interacts with almost all metals.

dilute sulfuric acid reacts with metals like a normal acid. As a result of the reaction, a salt with an acidic residue SO4 and hydrogen are formed.

Zn + H2SO4 = ZnSO4 + H2

BUT concentrated sulfuric acid is a very strong oxidizing agent. It oxidizes all metals, regardless of their position in the voltage series. And when reacting with metals, it itself is reduced to SO2. Hydrogen is not released.

Сu + 2 H2SO4 (conc) = CuSO4 + SO2 + 2H2O

Zn + 2 H2SO4 (conc) = ZnSO4 + SO2 + 2H2O

But gold, iron, aluminum, platinum group metals do not oxidize in sulfuric acid. Therefore, sulfuric acid is transported in steel tanks.

Sulfuric acid salts, which are obtained as a result of such reactions, are called sulfates. They are colorless and crystallize easily. Some of them are highly soluble in water. Only CaSO4 and PbSO4 are sparingly soluble. BaSO4 is almost insoluble in water.

Interaction with bases

The reaction of an acid with a base is called a neutralization reaction. As a result of the neutralization reaction of sulfuric acid, a salt containing the acid residue SO4 and water H2O is formed.

Examples of sulfuric acid neutralization reactions:

H2SO4 + 2 NaOH = Na2SO4 + 2 H2O

H2SO4 + CaOH = CaSO4 + 2 H2O

Sulfuric acid enters into a neutralization reaction with both soluble and insoluble bases.

Since there are two hydrogen atoms in the sulfuric acid molecule, and two bases are required to neutralize it, it belongs to dibasic acids.

Interaction with basic oxides

From the school chemistry course, we know that oxides are called complex substances, which include two chemical elements, one of which is oxygen in the oxidation state -2. Basic oxides are called oxides of 1, 2 and some 3 valence metals. Examples of basic oxides: Li2O, Na2O, CuO, Ag2O, MgO, CaO, FeO, NiO.

With basic oxides, sulfuric acid enters into a neutralization reaction. As a result of such a reaction, as in the reaction with bases, salt and water are formed. The salt contains the acid residue SO4.

CuO + H2SO4 = CuSO4 + H2O

Salt interaction

Sulfuric acid reacts with salts of weaker or volatile acids, displacing these acids from them. As a result of this reaction, a salt with an acidic residue SO4 and an acid

H2SO4+BaCl2=BaSO4+2HCl

The use of sulfuric acid and its compounds

Barium porridge BaSO4 is able to delay x-rays. Filling it with the hollow organs of the human body, radiologists examine them.

In medicine and construction, natural gypsum CaSO4 * 2H2O, calcium sulfate hydrate is widely used. Glauber's salt Na2SO4 * 10H2O is used in medicine and veterinary medicine, in the chemical industry - for the production of soda and glass. Copper sulfate CuSO4 * 5H2O is known to gardeners and agronomists who use it to control pests and plant diseases.

Sulfuric acid is widely used in various industries: chemical, metalworking, petroleum, textile, leather and others.