Structural formula
True, empirical, or gross formula: H2SO4
Chemical composition of Sulfuric acid
Molecular weight: 98.076
Sulfuric acid H 2 SO 4 is a strong dibasic acid corresponding to the highest oxidation state of sulfur (+6). Under normal conditions, concentrated sulfuric acid is a heavy, oily liquid, colorless and odorless, with a sour “copper” taste. In technology, sulfuric acid is called its mixture with both water and sulfuric anhydride SO 3. If the molar ratio of SO 3: H 2 O is less than 1, then it is an aqueous solution of sulfuric acid; if it is greater than 1, it is a solution of SO 3 in sulfuric acid (oleum).
Name
In the 18th-19th centuries, sulfur for gunpowder was produced from sulfur pyrite (pyrite) in vitriol factories. Sulfuric acid at that time was called “oil of vitriol” (as a rule, it was a crystalline hydrate, with a consistency reminiscent of oil), obviously hence the origin of the name of its salts (or rather, crystalline hydrates) - vitriol.
Preparation of sulfuric acid
Industrial (contact) method
In industry, sulfuric acid is produced by the oxidation of sulfur dioxide (sulfur dioxide gas formed during the combustion of sulfur or sulfur pyrites) to trioxide (sulfuric anhydride), followed by the reaction of SO 3 with water. The sulfuric acid obtained by this method is also called contact acid (concentration 92-94%).
Nitrose (tower) method
Previously, sulfuric acid was produced exclusively by the nitrous method in special towers, and the acid was called tower acid (concentration 75%). The essence of this method is the oxidation of sulfur dioxide with nitrogen dioxide in the presence of water.
Another way
In those rare cases when hydrogen sulfide (H 2 S) displaces sulfate (SO 4 -) from the salt (with the metals Cu, Ag, Pb, Hg), the by-product is sulfuric acid. Sulfides of these metals have the highest strength, as well as a distinctive black color.
Physical and physico-chemical properties
A very strong acid, at 18 o C pK a (1) = −2.8, pK a (2) = 1.92 (K z 1.2 10 -2); bond lengths in the molecule S=O 0.143 nm, S-OH 0.154 nm, HOSOH angle 104°, OSO 119°; boils, forming an azeotropic mixture (98.3% H 2 SO 4 and 1.7% H 2 O with a boiling point of 338.8 ° C). Sulfuric acid, corresponding to 100% H 2 SO 4 content, has a composition (%): H 2 SO 4 99.5, HSO 4 - - 0.18, H 3 SO 4 + - 0.14, H 3 O + - 0.09, H 2 S 2 O 7, - 0.04, HS 2 O 7 - - 0.05. Miscible with water and SO 3 in all proportions. In aqueous solutions, sulfuric acid almost completely dissociates into H 3 O + , HSO 3 + , and 2HSO 4 - . Forms hydrates H 2 SO 4 ·nH 2 O, where n = 1, 2, 3, 4 and 6.5.
Oleum
Solutions of sulfuric anhydride SO 3 in sulfuric acid are called oleum, they form two compounds H 2 SO 4 SO 3 and H 2 SO 4 2SO 3. Oleum also contains pyrosulfuric acids. The boiling point of aqueous solutions of sulfuric acid increases with an increase in its concentration and reaches a maximum at a content of 98.3% H 2 SO 4 . The boiling point of oleum decreases with increasing SO3 content. With an increase in the concentration of aqueous solutions of sulfuric acid, the total vapor pressure over the solutions decreases and at a content of 98.3% H 2 SO 4 reaches a minimum. As the concentration of SO 3 in oleum increases, the total vapor pressure above it increases. The vapor pressure over aqueous solutions of sulfuric acid and oleum can be calculated by the equation:
log p=A-B/T+2.126
the values of coefficients A and B depend on the concentration of sulfuric acid. Steam over aqueous solutions of sulfuric acid consists of a mixture of water vapor, H 2 SO 4 and SO 3, while the composition of the vapor differs from the composition of the liquid at all concentrations of sulfuric acid, except for the corresponding azeotropic mixture. As temperature increases, dissociation increases. The oleum H 2 SO 4 ·SO 3 has the maximum viscosity; with increasing temperature, η decreases. The electrical resistance of sulfuric acid is minimal at a concentration of SO 3 and 92% H 2 SO 4 and maximum at a concentration of 84 and 99.8% H 2 SO 4 . For oleum, the minimum ρ is at a concentration of 10% SO 3. With increasing temperature, ρ of sulfuric acid increases. Dielectric constant of 100% sulfuric acid 101 (298.15 K), 122 (281.15 K); cryoscopic constant 6.12, ebullioscopic constant 5.33; the diffusion coefficient of sulfuric acid vapor in air varies depending on temperature; D = 1.67·10⁻⁵T3/2 cm²/s.
Chemical properties
Sulfuric acid in concentrated form when heated is a fairly strong oxidizing agent. Oxidizes HI and partially HBr to free halogens. Oxidizes many metals (exceptions: Au, Pt, Ir, Rh, Ta.). In this case, concentrated sulfuric acid is reduced to SO 2. In the cold in concentrated sulfuric acid, Fe, Al, Cr, Co, Ni, Ba are passivated and reactions do not occur. The most powerful reducing agents reduce concentrated sulfuric acid to S and H 2 S. Concentrated sulfuric acid absorbs water vapor, so it is used for drying gases, liquids and solids, for example, in desiccators. However, concentrated H 2 SO 4 is partially reduced by hydrogen, which is why it cannot be used for drying it. By splitting water from organic compounds and leaving behind black carbon (charcoal), concentrated sulfuric acid leads to charring of wood, sugar and other substances. Dilute H 2 SO 4 interacts with all metals located in the electrochemical voltage series to the left of hydrogen with its release. The oxidizing properties of dilute H 2 SO 4 are uncharacteristic. Sulfuric acid forms two series of salts: medium - sulfates and acidic - hydrosulfates, as well as esters. Peroxomonosulfuric (or Caro acid) H 2 SO 5 and peroxodisulfuric H 2 S 2 O 8 acids are known. Sulfuric acid also reacts with basic oxides to form sulfate and water. In metalworking plants, a solution of sulfuric acid is used to remove a layer of metal oxide from the surface of metal products that are subjected to high heat during the manufacturing process. Thus, iron oxide is removed from the surface of sheet iron by the action of a heated solution of sulfuric acid. A qualitative reaction to sulfuric acid and its soluble salts is their interaction with soluble barium salts, which results in the formation of a white precipitate of barium sulfate, insoluble in water and acids, for example.
Application
Sulfuric acid is used:
- in ore processing, especially in the extraction of rare elements, including uranium, iridium, zirconium, osmium, etc.;
- in the production of mineral fertilizers;
- as an electrolyte in lead batteries;
- for obtaining various mineral acids and salts;
- in the production of chemical fibers, dyes, smoke-forming and explosives;
- in the oil, metalworking, textile, leather and other industries;
- in the food industry - registered as food additive E513 (emulsifier);
- in industrial organic synthesis in reactions:
- dehydration (production of diethyl ether, esters);
- hydration (ethanol from ethylene);
- sulfonation (synthetic detergents and intermediates in the production of dyes);
- alkylation (production of isooctane, polyethylene glycol, caprolactam), etc.
- For the restoration of resins in filters in the production of distilled water.
World production of sulfuric acid is approx. 160 million tons per year. The largest consumer of sulfuric acid is the production of mineral fertilizers. For P 2 O 5 phosphate fertilizers, 2.2-3.4 times more sulfuric acid is consumed by mass, and for (NH 4) 2 SO 4 sulfuric acid 75% of the mass of consumed (NH 4) 2 SO 4. Therefore, sulfuric acid plants tend to be built in conjunction with plants for the production of mineral fertilizers.
Historical information
Sulfuric acid has been known since ancient times, occurring in nature in free form, for example, in the form of lakes near volcanoes. Perhaps the first mention of acid gases produced by the calcination of alum or iron sulfate of the “green stone” is found in writings attributed to the Arab alchemist Jabir ibn Hayyan. In the 9th century, the Persian alchemist Ar-Razi, calcining a mixture of iron and copper sulfate (FeSO 4 7H 2 O and CuSO 4 5H 2 O), also obtained a solution of sulfuric acid. This method was improved by the European alchemist Albert Magnus, who lived in the 13th century. The scheme for producing sulfuric acid from ferrous sulfate is the thermal decomposition of iron (II) sulfate followed by cooling of the mixture. The works of the alchemist Valentin (13th century) describe a method for producing sulfuric acid by absorbing gas (sulfuric anhydride) released by burning a mixture of sulfur and nitrate powders with water. Subsequently, this method formed the basis of the so-called. “chamber” method, carried out in small chambers lined with lead, which does not dissolve in sulfuric acid. In the USSR, this method existed until 1955. Alchemists of the 15th century also knew a method for producing sulfuric acid from pyrite - sulfur pyrite, a cheaper and more common raw material than sulfur. Sulfuric acid has been produced in this way for 300 years, in small quantities in glass retorts. Subsequently, in connection with the development of catalysis, this method replaced the chamber method for the synthesis of sulfuric acid. Currently, sulfuric acid is produced by the catalytic oxidation (on V 2 O 5) of sulfur oxide (IV) to sulfur oxide (VI), and subsequent dissolution of sulfur oxide (VI) in 70% sulfuric acid to form oleum. In Russia, the production of sulfuric acid was first organized in 1805 near Moscow in the Zvenigorod district. In 1913, Russia ranked 13th in the world in the production of sulfuric acid.
additional information
Tiny droplets of sulfuric acid can form in the middle and upper layers of the atmosphere as a result of the reaction of water vapor and volcanic ash containing large quantities of sulfur. The resulting suspension, due to the high albedo of sulfuric acid clouds, makes it difficult for sunlight to reach the surface of the planet. Therefore (and also as a result of the large number of tiny particles of volcanic ash in the upper atmosphere, which also impede sunlight access to the planet), significant climate changes can occur after particularly strong volcanic eruptions. For example, as a result of the eruption of the Ksudach volcano (Kamchatka Peninsula, 1907), an increased concentration of dust in the atmosphere remained for about 2 years, and characteristic noctilucent clouds of sulfuric acid were observed even in Paris. The explosion of Mount Pinatubo in 1991, which released 3 × 10 7 tons of sulfur into the atmosphere, resulted in 1992 and 1993 being significantly colder than 1991 and 1994.
Standards
- Technical sulfuric acid GOST 2184-77
- Battery sulfuric acid. Technical specifications GOST 667-73
- Sulfuric acid of special purity. Technical specifications GOST 1422-78
- Reagents. Sulfuric acid. Technical specifications GOST 4204-77
Physical properties of sulfuric acid:
Heavy oily liquid (“oil of vitriol”);
density 1.84 g/cm3; non-volatile, highly soluble in water - with strong heating; t°pl. = 10.3°C, t°boil. = 296°C, very hygroscopic, has water-removing properties (charring of paper, wood, sugar).
The heat of hydration is so great that the mixture can boil, splash and cause burns. Therefore, it is necessary to add acid to water, and not vice versa, since when water is added to acid, lighter water will end up on the surface of the acid, where all the heat generated will be concentrated.
Industrial production of sulfuric acid (contact method):
1) 4FeS 2 + 11O 2 → 2Fe 2 O 3 + 8SO 2
2) 2SO 2 + O 2 V 2 O 5 → 2SO 3
3) nSO 3 + H 2 SO 4 → H 2 SO 4 nSO 3 (oleum)
Crushed, purified, wet pyrite (sulfur pyrite) is poured into the kiln on top for firing in " fluidized bed". Air enriched with oxygen is passed from below (counterflow principle).
Furnace gas comes out of the furnace, the composition of which is: SO 2, O 2, water vapor (the pyrite was wet) and tiny particles of cinder (iron oxide). The gas is purified from impurities of solid particles (in a cyclone and electric precipitator) and water vapor (in a drying tower).
In a contact apparatus, sulfur dioxide is oxidized using a catalyst V 2 O 5 (vanadium pentoxide) to increase the reaction rate. The process of oxidation of one oxide to another is reversible. Therefore, optimal conditions for the direct reaction are selected - increased pressure (since the direct reaction occurs with a decrease in the total volume) and a temperature not higher than 500 C (since the reaction is exothermic).
In the absorption tower, sulfur oxide (VI) is absorbed by concentrated sulfuric acid.
Absorption by water is not used, because sulfur oxide dissolves in water with the release of a large amount of heat, so the resulting sulfuric acid boils and turns into steam. To prevent the formation of sulfuric acid fog, use 98% concentrated sulfuric acid. Sulfur oxide dissolves very well in such an acid, forming oleum: H 2 SO 4 nSO 3
Chemical properties of sulfuric acid:
H 2 SO 4 is a strong dibasic acid, one of the strongest mineral acids; due to its high polarity, the H – O bond is easily broken.
1)
Sulfuric acid dissociates in aqueous solution
, forming a hydrogen ion and an acidic residue:
H 2 SO 4 \u003d H + + HSO 4 -;
HSO 4 - \u003d H + + SO 4 2-.
Summary Equation:
H 2 SO 4 \u003d 2H + + SO 4 2-.
2) Interaction of sulfuric acid with metals:
Dilute sulfuric acid dissolves only metals in the voltage series to the left of hydrogen:
Zn 0 + H 2 +1 SO 4 (diluted) → Zn +2 SO 4 + H 2
3)
Reaction of sulfuric acidwith basic oxides:
CuO + H 2 SO 4 → CuSO 4 + H 2 O
4)
Reaction of sulfuric acid withhydroxides:
H 2 SO 4 + 2NaOH → Na 2 SO 4 + 2H 2 O
H 2 SO 4 + Cu(OH) 2 → CuSO 4 + 2H 2 O
5)
Exchange reactions with salts:
BaCl 2 + H 2 SO 4 → BaSO 4 ↓ + 2HCl
The formation of a white precipitate of BaSO 4 (insoluble in acids) is used to detect sulfuric acid and soluble sulfates (qualitative reaction to sulfate ion).
Special properties of concentrated H 2 SO 4:
1) Concentrated sulfuric acid is strong oxidizing agent ; when interacting with metals (except Au, Pt), it is reduced to S +4 O 2, S 0 or H 2 S -2 depending on the activity of the metal. Without heating, it does not react with Fe, Al, Cr - passivation. When interacting with metals with variable valency, the latter oxidize to higher oxidation states than in the case of a dilute acid solution: Fe 0→ Fe 3+ , Cr 0→ Cr 3+ , Mn 0→Mn 4+,Sn 0→ Sn 4+
Active metal
8 Al + 15 H 2 SO 4 (conc.) → 4Al 2 (SO 4) 3 + 12H 2 O + 3 H2S
4│2Al 0 – 6 e- → 2Al 3+ - oxidation
3│ S 6+ + 8e → S 2– recovery
4Mg+ 5H 2 SO 4 → 4MgSO 4 + H 2 S + 4H 2 O
Medium activity metal
2Cr + 4 H 2 SO 4 (conc.) → Cr 2 (SO 4) 3 + 4 H 2 O + S
1│ 2Cr 0 – 6e →2Cr 3+ - oxidation
1│ S 6+ + 6e → S 0 – recovery
Metal inactive
2Bi + 6H 2 SO 4 (conc.) → Bi 2 (SO 4) 3 + 6H 2 O + 3 SO 2
1│ 2Bi 0 – 6e → 2Bi 3+ – oxidation
3│ S 6+ + 2e →S 4+ - recovery
2Ag + 2H 2 SO 4 → Ag 2 SO 4 + SO 2 + 2H 2 O
2) Concentrated sulfuric acid oxidizes some non-metals, usually to the maximum oxidation state, and is itself reduced toS+4O2:
C + 2H 2 SO 4 (conc) → CO 2 + 2SO 2 + 2H 2 O
S+ 2H 2 SO 4 (conc) → 3SO 2 + 2H 2 O
2P+ 5H 2 SO 4 (conc) → 5SO 2 + 2H 3 PO 4 + 2H 2 O
3) Oxidation of complex substances:
Sulfuric acid oxidizes HI and HBr to free halogens:
2 KBr + 2H 2 SO 4 = K 2 SO 4 + SO 2 + Br 2 + 2H 2 O
2 KI + 2H 2 SO 4 = K 2 SO 4 + SO 2 + I 2 + 2H 2 O
Concentrated sulfuric acid cannot oxidize chloride ions to free chlorine, which makes it possible to obtain HCl by the exchange reaction:
NaCl + H 2 SO 4 (conc.) = NaHSO 4 + HCl
Sulfuric acid removes chemically bound water from organic compounds containing hydroxyl groups. Dehydration of ethyl alcohol in the presence of concentrated sulfuric acid produces ethylene:
C 2 H 5 OH \u003d C 2 H 4 + H 2 O.
The charring of sugar, cellulose, starch and other carbohydrates upon contact with sulfuric acid is also explained by their dehydration:
C 6 H 12 O 6 + 12H 2 SO 4 = 18H 2 O + 12SO 2 + 6CO 2.
It has a historical name: oil of vitriol. The study of acid began in ancient times; the Greek physician Dioscorides, the Roman naturalist Pliny the Elder, the Islamic alchemists Geber, Razi and Ibn Sina, and others described it in their works. In the Sumerians there was a list of vitriols, which were classified according to the color of the substance. Nowadays, the word “vitriol” combines crystalline hydrates of divalent metal sulfates.
In the 17th century, the German-Dutch chemist Johann Glauber prepared sulfuric acid by burning sulfur with (KNO3) in the presence of In 1736, Joshua Ward (a pharmacist from London) used this method in production. This time can be considered the starting point when sulfuric acid began to be produced on a large scale. Its formula (H2SO4), as is commonly believed, was established by the Swedish chemist Berzelius (1779-1848) a little later.
Berzelius, using alphabetic symbols (indicating chemical elements) and lower digital indices (indicating the number of atoms of a given type in a molecule), established that one molecule contains 1 sulfur atom (S), 2 hydrogen atoms (H) and 4 oxygen atoms (O ). Since that time, the qualitative and quantitative composition of the molecule became known, that is, sulfuric acid was described in the language of chemistry.
Showing in graphical form the relative arrangement of atoms in the molecule and the chemical bonds between them (they are usually denoted by lines), it informs that in the center of the molecule there is a sulfur atom, which is connected by double bonds with two oxygen atoms. With the other two oxygen atoms, each of which has a hydrogen atom attached, the same sulfur atom is connected by single bonds.
Properties
Sulfuric acid is a slightly yellowish or colorless, viscous liquid, soluble in water at any concentration. It is a strong mineral and is highly aggressive towards metals (concentrated does not interact with iron without heating, but passivates it), rocks, animal tissues or other materials. It is characterized by high hygroscopicity and pronounced properties of a strong oxidizing agent. At a temperature of 10.4 °C, the acid solidifies. When heated to 300 °C, almost 99% of the acid loses sulfuric anhydride (SO3).
Its properties vary depending on the concentration of its aqueous solution. There are common names for acid solutions. Up to 10% acid is considered dilute. Battery - from 29 to 32%. When the concentration is less than 75% (as established in GOST 2184), it is called tower. If the concentration is 98%, then it will already be concentrated sulfuric acid. The formula (chemical or structural) remains unchanged in all cases.
When concentrated sulfuric anhydride is dissolved in sulfuric acid, oleum or fuming sulfuric acid is formed; its formula can be written as follows: H2S2O7. Pure acid (H2S2O7) is a solid with a melting point of 36 °C. The hydration reactions of sulfuric acid are characterized by the release of heat in large quantities.
Dilute acid reacts with metals, reacting with which it exhibits the properties of a strong oxidizing agent. In this case, sulfuric acid is reduced; the formula of the formed substances containing a reduced (to +4, 0 or -2) sulfur atom can be: SO2, S or H2S.
Reacts with non-metals such as carbon or sulfur:
2 H2SO4 + C → 2 SO2 + CO2 + 2 H2O
2 H2SO4 + S → 3 SO2 + 2 H2O
Reacts with sodium chloride:
H2SO4 + NaCl → NaHSO4 + HCl
It is characterized by the reaction of electrophilic substitution of a hydrogen atom attached to the benzene ring of an aromatic compound by the -SO3H group.
Receipt
In 1831, the contact method for producing H2SO4, which is currently the main one, was patented. Today, most sulfuric acid is produced using this method. The raw material used is sulfide ore (usually iron pyrite FeS2), which is fired in special furnaces, which produces a roasting gas. Since the gas temperature is 900 °C, it is cooled with sulfuric acid with a concentration of 70%. Then the gas is cleaned from dust in the cyclone and electrostatic precipitator, in washing towers with acid with a concentration of 40 and 10% of catalytic poisons (As2O5 and fluorine), and in wet electrostatic precipitators from acid aerosol. Next, the roasting gas containing 9% sulfur dioxide (SO2) is dried and fed into the contact apparatus. After passing through 3 layers of vanadium catalyst, SO2 is oxidized to SO3. Concentrated sulfuric acid is used to dissolve the resulting sulfuric anhydride. The formula for a solution of sulfuric anhydride (SO3) in anhydrous sulfuric acid is H2S2O7. In this form, oleum in steel tanks is transported to the consumer, where it is diluted to the desired concentration.
Application
Due to its different chemical properties, H2SO4 has a wide range of applications. In the production of acid itself, as an electrolyte in lead-acid batteries, for the manufacture of various cleaning agents, it is also an important reagent in the chemical industry. It is also used in the production of: alcohols, plastics, dyes, rubber, ether, adhesives, soaps and detergents, pharmaceuticals, pulp and paper, petroleum products.
Acids are chemical compounds consisting of hydrogen atoms and acidic residues, for example, SO4, SO3, PO4, etc. They are inorganic and organic. The first include hydrochloric, phosphoric, sulfide, nitric, and sulfuric acid. The second ones include acetic acid, palmitic acid, formic acid, stearic acid, etc.
What is sulfuric acid
This acid consists of two hydrogen atoms and the acidic 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 voltage series of metals (that is, with not the most active ones), the following substances are formed: sulfate of the metal with which the interaction occurs, water and sulfur dioxide. 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 slightly differently. As a result of this 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 look at 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 .
