Today we invite you to talk about the preparation and use of a solution of hydrochloric acid and the acid itself in particular. It has found wide application in various branches of human activity. It is also used in medicine.
The use of hydrochloric acid in medicine.
Hydrochloric acid contributes to the following processes:
balances the acid-base balance of the body;
treats oncological diseases;
inhibits the development of malignant tumors;
digests proteins in the stomach.
Treatment of low acidity of the stomach with hydrochloric acid.
How to prepare a solution of hydrochloric acid and before treating low acidity, you must consult a doctor and consult with him and in no case make any attempts at self-treatment. He will prescribe you a treatment, according to the individual characteristics of your body, as well as taking into account the results of your tests.
In addition to drugs with hydrochloric acid, you can take drugs that help stimulate the production of hydrochloric acid in the body. In addition, to date, herbal remedies (wormwood, peppermint, calamus) have been developed that also stimulate the production of hydrochloric acid in the body, thereby helping to increase the level of stomach acidity.
With the help of preparations containing hydrochloric acid, it is possible to prevent stomach cancer, reduce the risk of hepatitis, as well as diseases such as diabetes, psoriasis, rheumatoid arthritis, eczema, cholelithiasis, rosacea, urticaria, asthma and many others.
How to prepare a hydrochloric acid solution and how to use it.
In order not to wonder how to prepare a hydrochloric acid solution, we suggest that you study the following information that will be useful to you. The prepared solution with hydrochloric acid is sometimes called aqua regia. This cooking recipe was invented by Bolotov and in order to cook it, we need the following substances. In a liter jar of water, add 0.5 cups of grape vinegar, then 1-2 teaspoons of sulfuric acid and 1 tablespoon of 38% hydrochloric acid, without violating this sequence. At the end, you need to add 4 tablets of nitroglycerin. With the help of the resulting hydrochloric acid solution and other ingredients, it is possible to break down cancer cells that provoke the appearance of a disease such as cancer. As for the application, you need to use a similar solution three times a day, 1-2 teaspoons, which are diluted in 0.5 cups of liquid (this can be ordinary water, tea or coffee) before or after meals. If the disease has taken an acute form, the dose can be increased to 1 tablespoon per half glass of water.
Treatment with hydrochloric acid solution of hemorrhoids.
In connection with a sedentary lifestyle, a disease such as hemorrhoids can develop. For the treatment of this disease, traditional medicine is most often resorted to. The use of such a recipe is considered very effective. We take half a glass of water and add 1-2 tablespoons of a 3-5% hydrochloric acid solution there. The resulting solution is recommended to use half a cup before meals.
Thus, knowing how to prepare a solution of hydrochloric acid, and knowing what it is used for, you have a chance, at home, to recover from many diseases.
Receipt. Hydrochloric acid is produced by dissolving hydrogen chloride in water.
Pay attention to the device shown in the figure on the left. It is used to produce hydrochloric acid. During the process of obtaining hydrochloric acid, monitor the gas outlet tube, it should be near the water level, and not be immersed in it. If this is not followed, then due to the high solubility of hydrogen chloride, water will enter the test tube with sulfuric acid and an explosion may occur.
In industry, hydrochloric acid is usually produced by burning hydrogen in chlorine and dissolving the reaction product in water.
physical properties. By dissolving hydrogen chloride in water, even a 40% hydrochloric acid solution with a density of 1.19 g/cm 3 can be obtained. However, commercially available concentrated hydrochloric acid contains about 0.37 mass fractions, or about 37% hydrogen chloride. The density of this solution is approximately 1.19 g/cm 3 . When an acid is diluted, the density of its solution decreases.
Concentrated hydrochloric acid is an invaluable solution, highly fuming in moist air, with a pungent odor due to the release of hydrogen chloride.
Chemical properties. Hydrochloric acid has a number of common properties that are characteristic of most acids. In addition, it has some specific properties.
Properties of HCL in common with other acids: 1) Color change of indicators 2) interaction with metals 2HCL + Zn → ZnCL 2 + H 2 3) Interaction with basic and amphoteric oxides: 2HCL + CaO → CaCl 2 + H 2 O; 2HCL + ZnO → ZnHCL 2 + H 2 O 4) Interaction with bases: 2HCL + Cu (OH) 2 → CuCl 2 + 2H 2 O 5) Interaction with salts: 2HCL + CaCO 3 → H 2 O + CO 2 + CaCL 2
Specific properties of HCL: 1) Interaction with silver nitrate (silver nitrate is a reagent for hydrochloric acid and its salts); a white precipitate will form, which does not dissolve in water or acids: HCL + AgNO3 → AgCL↓ + HNO 3 2O+3CL2
Application. A huge amount of hydrochloric acid is consumed to remove iron oxides before coating products from this metal with other metals (tin, chromium, nickel). In order for hydrochloric acid to react only with oxides, but not with metal, special substances are added to it, which are called inhibitors. Inhibitors- Substances that slow down reactions.
Hydrochloric acid is used to obtain various chlorides. It is used to produce chlorine. Very often, a solution of hydrochloric acid is prescribed to patients with low acidity of gastric juice. Hydrochloric acid is found in everyone in the body, it is part of the gastric juice, which is necessary for digestion.
In the food industry, hydrochloric acid is used only in the form of a solution. It is used to regulate acidity in the production of citric acid, gelatin or fructose (E 507).
Do not forget that hydrochloric acid is dangerous for the skin. It poses an even greater danger to the eyes. Influencing a person, it can cause tooth decay, irritation of mucous membranes, and suffocation.
In addition, hydrochloric acid is actively used in electroplating and hydrometallurgy (scale removal, rust removal, leather treatment, chemical reagents, as a rock solvent in oil production, in the production of rubbers, sodium glutamate, soda, Cl 2). Hydrochloric acid is used for the regeneration of Cl 2 in organic synthesis (to obtain vinyl chloride, alkyl chlorides, etc.) It can be used as a catalyst in the production of diphenylolpropane, benzene alkylation.
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To prepare the solution, it is necessary to mix the calculated amounts of an acid of a known concentration and distilled water.
Example.
It is necessary to prepare 1 liter of HCL solution with a concentration of 6% by weight. from hydrochloric acid with a concentration of 36% wt.(such a solution is used in KM carbonate meters manufactured by OOO NPP Geosfera)
.
By table 2determine the molar concentration of acid with a weight fraction of 6% wt. (1.692 mol/l) and 36% wt. (11.643 mol/l).
Calculate the volume of concentrated acid containing the same amount of HCl (1.692 g-eq.) as in the prepared solution:
1.692 / 11.643 = 0.1453 liters.
Therefore, by adding 145 ml of acid (36% by weight) to 853 ml of distilled water, you get a solution of a given weight concentration.
Experience 5. Preparation of aqueous solutions of hydrochloric acid of a given molar concentration.
To prepare a solution with the desired molar concentration (Mp), it is necessary to pour one volume of concentrated acid (V) into a volume (Vv) of distilled water, calculated by the ratioVv \u003d V (M / Mp - 1)
where M is the molar concentration of the initial acid.
If the concentration of the acid is not known, determine it from the density usingtable 2.
Example.
The weight concentration of the acid used is 36.3% wt. It is necessary to prepare 1 l of an aqueous solution of HCL with a molar concentration of 2.35 mol/l.
By table 1find by interpolating the values 12.011 mol/l and 11.643 mol/l the molar concentration of the acid used:
11.643 + (12.011 - 11.643) (36.3 - 36.0) = 11.753 mol/l
Use the above formula to calculate the volume of water:
Vv \u003d V (11.753 / 2.35 - 1) \u003d 4 V
Taking Vv + V = 1 l, get the volume values: Vv = 0.2 l and V = 0.8 l.
Therefore, to prepare a solution with a molar concentration of 2.35 mol / l, you need to pour 200 ml of HCL (36.3% wt.) In 800 ml of distilled water.
Questions and tasks:
What is the concentration of a solution?
What is the normality of a solution?
How many grams of sulfuric acid is contained in the solution if 20 ml is used for neutralization. sodium hydroxide solution, the titer of which is 0.004614?
Materials and equipment:
Working process:
Iodometric method
Reagents:
1. Potassium iodide chemically pure crystalline, not containing free iodine.
Examination. Take 0.5 g of potassium iodide, dissolve in 10 ml of distilled water, add 6 ml of buffer mixture and 1 ml of 0.5% starch solution. There should be no blueing of the reagent.
2. Buffer mixture: pH = 4.6. Mix 102 ml of a molar solution of acetic acid (60 g of 100% acid in 1 liter of water) and 98 ml of a molar solution of sodium acetate (136.1 g of crystalline salt in 1 liter of water) and bring to 1 liter with distilled water, previously boiled.
3. 0.01 N sodium hyposulfite solution.
4. 0.5% starch solution.
5. 0.01 N solution of potassium dichromate. Setting the titer of 0.01 N hyposulfite solution is carried out as follows: pour 0.5 g of pure potassium iodide into the flask, dissolve in 2 ml of water, first add 5 ml of hydrochloric acid (1: 5), then 10 ml of 0.01 N solution of dichromate potassium and 50 ml of distilled water. The released iodine is titrated with sodium hyposulfite in the presence of 1 ml of starch solution added at the end of the titration. The correction factor for the sodium hyposulfite titer is calculated using the following formula: K = 10/a, where a is the number of milliliters of sodium hyposulfite used for titration.
Analysis progress:
a) add 0.5 g of potassium iodide into a conical flask;
b) add 2 ml of distilled water;
c) stir the contents of the flask until potassium iodide dissolves;
d) add 10 ml of a buffer solution if the alkalinity of the test water is not higher than 7 mg/eq. If the alkalinity of the test water is higher than 7 mg/eq, then the amount of milliliters of the buffer solution should be 1.5 times the alkalinity of the test water;
e) add 100 ml of the test water;
e) titrate with hyposulfite until the solution turns pale yellow;
g) add 1 ml of starch;
h) titrate with hyposulfite until the blue color disappears.
X \u003d 3.55 N K
where H is the number of ml of hyposulfite used for titration,
K - correction factor to the titer of sodium hyposulfite.
Questions and tasks:
What is the iodometric method?
What is pH?
LPZ #6: Determination of the chloride ion
Purpose of work:
Materials and equipment: drinking water, litmus paper, ashless filter, potassium chromate, silver nitrate, titrated sodium chloride solution,
Working process:
Depending on the results of the qualitative determination, 100 cm 3 of the test water or its smaller volume (10-50 cm 3) are selected and adjusted to 100 cm 3 with distilled water. Without dilution, chlorides are determined in concentrations up to 100 mg / dm 3. The pH of the titratable sample should be in the range of 6-10. If the water is cloudy, it is filtered through an ashless filter washed with hot water. If the water has a color greater than 30°, the sample is decolorized by adding aluminum hydroxide. To do this, 6 cm 3 of a suspension of aluminum hydroxide is added to 200 cm 3 of the sample, and the mixture is shaken until the liquid becomes colorless. The sample is then filtered through an ashless filter. The first portions of the filtrate are discarded. The measured volume of water is introduced into two conical flasks and 1 cm 3 of a solution of potassium chromate is added. One sample is titrated with a solution of silver nitrate until a faint orange tint appears, the second sample is used as a control sample. With a significant content of chlorides, a precipitate of AgCl is formed, which interferes with the determination. In this case, 2-3 drops of titrated NaCl solution are added to the titrated first sample until the orange tint disappears, then the second sample is titrated, using the first one as a control sample.
The definition is hindered by: orthophosphates in concentrations exceeding 25 mg/dm 3 ; iron at a concentration of more than 10 mg / dm 3. Bromides and iodides are determined in concentrations equivalent to Cl - . At their usual content in tap water, they do not interfere with the determination.
2.5. Processing of results.
where v is the amount of silver nitrate used for titration, cm 3;
K - correction factor to the titer of silver nitrate solution;
g is the amount of chlorine ion corresponding to 1 cm 3 solution of silver nitrate, mg;
V is the volume of the sample taken for determination, cm 3 .
Questions and tasks:
Ways to determine chloride ions?
Conductometric method for determining chloride ions?
Argentometry.
Purpose of work:
Materials and equipment:
Experience 1. Determination of the total hardness of tap water
Use a measuring cylinder to measure 50 ml of tap water (from the tap) and pour it into a 250 ml flask, add 5 ml of ammonia buffer solution and the indicator - eriochrome black T - until a pink color appears (several drops or several crystals). Fill the burette with EDTA solution 0.04 N (synonyms - Trilon B, complexon III) to zero.
Titrate the prepared sample slowly with constant stirring with a solution of complexone III until the pink color changes to blue. Record the result of the titration. Repeat titration one more time.
If the difference in titration results exceeds 0.1 ml, then titrate the water sample a third time. Determine the average volume of complexone III (V K, SR) used for titration of water, and calculate the total hardness of water from it.
W TOTAL = , (20) where V 1 is the volume of analyzed water, ml; V K, SR - the average volume of the complexone III solution, ml; N K is the normal concentration of complexone III solution, mol/l; 1000 is the conversion factor mol/l to mmol/l.
Record the results of the experiment in the table:
| V K,SR | N K | V 1 | F OVR |
Example 1. Calculate the hardness of water, knowing that 500 liters of it contains 202.5 g of Ca (HCO 3) 2.
Decision. 1 liter of water contains 202.5:500 \u003d 0.405 g of Ca (HCO 3) 2. The equivalent mass of Ca(HCO 3) 2 is 162:2 = 81 g/mol. Therefore, 0.405 g is 0.405:81 \u003d 0.005 equivalent masses or 5 mmol equiv / l.
Example 2. How many grams of CaSO 4 are contained in one cubic meter of water, if the hardness due to the presence of this salt is 4 mmol eq
CONTROL QUESTIONS
1. What cations are called hardness ions?
2. What technological indicator of water quality is called hardness?
3. Why can't hard water be used for steam recovery at thermal and nuclear power plants?
4. What softening method is called thermal? What chemical reactions take place during water softening by this method?
5. How is water softening carried out by precipitation? What reagents are used? What reactions take place?
6. Is it possible to soften water using ion exchange?
LPZ No. 8 "Photocolorimetric determination of the content of elements in solution"
The purpose of the work: to study the device and principle of operation of the photocolorimeter KFK - 2
PHOTOELECTROCOLORIMETERS. A photoelectric colorimeter is an optical device in which the monochromatization of the radiation flux is carried out using light filters. Colorimeter photoelectric concentration KFK - 2.
Purpose and technical data. Single-beam photocolorimeter KFK - 2
designed to measure the transmission, optical density and concentration of colored solutions, scattering suspensions, emulsions and colloidal solutions in the spectral region 315–980 nm. The entire spectral range is divided into spectral intervals, selected using light filters. Transmission measurement limits from 100 to 5% (optical density from 0 to 1.3). The main absolute error of transmission measurement is no more than 1%. Rice. General view of KFK-2. 1 - illuminator; 2 - handle for entering color filters; 3 - cell compartment; 4 - cuvette movement handle; 5 - handle (introducing photodetectors into the light flux) "Sensitivity"; 6 - knob for setting the device to 100% transmission; 7 - microammeter. Light filters. In order to isolate rays of certain wavelengths from the entire visible region of the spectrum in photocolorimeters, on the path of light fluxes, selective light absorbers - light filters are installed in front of absorbing solutions. Operating procedure
1. Plug in the colorimeter 15 minutes before you start measuring. During warming up, the cell compartment should be open (in this case, the shutter in front of the photodetector blocks the light beam).
2. Enter the working filter.
3. Set the minimum sensitivity of the colorimeter. To do this, set the "SENSITIVITY" knob to position "1", the "SETTING 100 ROUGH" knob - to the leftmost position.
4. Set the pointer of the colorimeter to zero using the ZERO potentiometer.
5. Place the control solution cuvette into the light beam.
6. Close the cell cover
7. Use the "SENSITIVITY" and "SETTING 100 ROUGH" and "FINE" knobs to set the pointer of the microammeter to the "100" division of the transmission scale.
8. By turning the handle of the cuvette chamber, place the cuvette with the test solution into the light flux.
9. Take readings on the colorimeter scale in the appropriate units (T% or D).
10. After finishing work, unplug the colorimeter, clean and dry the cuvette chamber. Determination of the concentration of a substance in a solution using KFK-2. When determining the concentration of a substance in a solution using a calibration curve, the following sequence should be observed:
examine three samples of potassium permanganate solution of various concentrations, write down the results in a journal.
Questions and tasks:
The device and principle of operation of KFK - 2
Basic literature for students:
1. The course of supporting notes for the program OP.06 Fundamentals of Analytical Chemistry. - allowance / A.G. Bekmukhamedova - teacher of general professional disciplines ASHT - Branch of FGBOU VPO OGAU; 2014
Additional literature for students:
1.Klyukvina E.Yu. Fundamentals of General and Inorganic Chemistry: textbook / E.Yu. Klyukvin, S.G. Bezryadin.-2nd ed.-Orenburg. Publishing Center OGAU, 2011 - 508 p.
Basic literature for teachers:
1. 1. Klyukvina E.Yu. Fundamentals of General and Inorganic Chemistry: textbook / E.Yu. Klyukvin, S.G. Bezryadin. - 2nd ed. - Orenburg. Publishing Center OGAU, 2011 - 508 p.
2. Klyukvina E.Yu. Laboratory notebook on analytical chemistry. - Orenburg: OGAU Publishing Center, 2012 - 68 pages
Additional literature for teachers:
1. 1. Klyukvina E.Yu. Fundamentals of General and Inorganic Chemistry: textbook / E.Yu. Klyukvin, S.G. Bezryadin.-2nd ed.-Orenburg. Publishing Center OGAU, 2011 - 508 p.
2. Klyukvina E.Yu. Laboratory notebook on analytical chemistry. - Orenburg: OGAU Publishing Center, 2012 - 68 pages
Hydrogen chloride is a gas about 1.3 times heavier than air. It is colorless, but with a sharp, suffocating and characteristic odor. At a temperature of minus 84C, hydrogen chloride passes from a gaseous to a liquid state, and at minus 112C it solidifies. Hydrogen chloride dissolves in water. One liter of H2O can absorb up to 500 ml of gas. Its solution is called hydrochloric or hydrochloric acid. Concentrated hydrochloric acid at 20C is characterized by the maximum possible basic substance, equal to 38%. The solution is a strong monobasic acid (it "smokes" in air, and forms an acid fog in the presence of moisture), it also has other names: hydrochloric acid, and according to Ukrainian nomenclature - chloride acid. The chemical formula can be represented as follows: HCl. The molar mass is 36.5 g/mol. The density of concentrated hydrochloric acid at 20C is 1.19 g/cm³. This is a harmful substance that belongs to the second hazard class.
In a "dry" form, hydrogen chloride cannot interact even with active metals, but in the presence of moisture, the reaction proceeds quite vigorously. This strong hydrochloric acid is capable of reacting with all metals that are to the left of hydrogen in the voltage series. In addition, it interacts with basic and amphoteric oxides, bases, and also with salts:
- Fe + 2HCl → FeCl2 + H2;
- 2HCl + CuO → CuCl2 + H2O;
- 3HCl + Fe(OH)3 → FeCl3 + 3H2O;
- 2HCl + Na2CO3 → 2NaCl + H2O + CO2;
- HCl + AgNO3 → AgCl↓ + HNO3.
In addition to the general properties characteristic of each strong acid, hydrochloric acid has reducing properties: in concentrated form, it reacts with various oxidizing agents, releasing free chlorine. Salts of this acid are called chlorides. Almost all of them dissolve well in water and completely dissociate into ions. Slightly soluble are: lead chloride PbCl2, silver chloride AgCl, monovalent mercury chloride Hg2Cl2 (calomel) and monovalent copper chloride CuCl. Hydrogen chloride is capable of entering into an addition reaction to a double or triple bond, with the formation of chlorine derivatives of organic compounds.
Under laboratory conditions, hydrogen chloride is obtained by exposure to dry concentrated sulfuric acid. The reaction under different conditions can proceed with the formation of sodium salts (acidic or medium):
- H2SO4 + NaCl → NaHSO4 + HCl
- H2SO4 + 2NaCl → Na2SO4 + 2HCl.
The first reaction goes to completion at low heating, the second - at higher temperatures. Therefore, in the laboratory, it is better to obtain hydrogen chloride by the first method, for which the amount of sulfuric acid is recommended to be taken from the calculation of obtaining the acid salt NaHSO4. Then, by dissolving hydrogen chloride in water, hydrochloric acid is obtained. In industry, it is obtained by burning hydrogen in an atmosphere of chlorine or by acting on dry sodium chloride (only the second with concentrated sulfuric acid. Hydrogen chloride is also obtained as a by-product during the chlorination of saturated organic compounds. In industry, hydrogen chloride obtained by one of the above methods is dissolved in special towers in which liquid is passed from top to bottom, and gas is supplied from bottom to top, that is, according to the principle of counterflow.
Hydrochloric acid is transported in special rubberized tanks or containers, as well as in polyethylene barrels with a capacity of 50 liters or glass bottles with a capacity of 20 liters. When there is a risk of formation of explosive hydrogen-air mixtures. Therefore, the contact of the hydrogen formed as a result of the reaction with air, as well as (with the help of anti-corrosion coatings) the contact of acid with metals, must be completely excluded. Before removing the apparatus and pipelines, where it was stored or transported, for repair, it is necessary to carry out nitrogen purges and control the state of the gas phase.
Hydrogen chloride is widely used in industrial production and in laboratory practice. It is used to obtain salts and as a reagent in analytical studies. Technical hydrochloric acid is produced in accordance with GOST 857-95 (the text is identical to the international standard ISO 905-78), the reagent is in accordance with GOST 3118-77. The concentration of the technical product depends on the brand and grade and can be 31.5%, 33% or 35%, and externally the product is yellowish in color due to the content of impurities of iron, chlorine and other chemicals. The reactive acid should be a colorless and transparent liquid with a mass fraction of 35 to 38%.
Structural formula
True, empirical, or gross formula: HCl
Chemical composition of hydrochloric acid
Molecular weight: 36.461
Hydrochloric acid(also hydrochloric, hydrochloric acid, hydrogen chloride) - a solution of hydrogen chloride (HCl) in water, a strong monobasic acid. Colorless, transparent, caustic liquid, "fuming" in air (technical hydrochloric acid is yellowish due to impurities of iron, chlorine, etc.). At a concentration of about 0.5%, it is present in the human stomach. The maximum concentration at 20 °C is 38% by weight, the density of such a solution is 1.19 g/cm³. Molar mass 36.46 g/mol. Salts of hydrochloric acid are called chlorides.
Physical properties
The physical properties of hydrochloric acid are highly dependent on the concentration of dissolved hydrogen chloride. When solidified, it gives crystalline hydrates of the compositions HCl H 2 O, HCl 2H 2 O, HCl 3H 2 O, HCl 6H 2 O.
Chemical properties
- Interaction with metals standing in a series of electrochemical potentials up to hydrogen, with the formation of a salt and the release of gaseous hydrogen.
- Interaction with metal oxides to form a soluble salt and water.
- Interaction with metal hydroxides to form a soluble salt and water (neutralization reaction).
- Interaction with metal salts formed by weaker acids, such as carbonic.
- Interaction with strong oxidizing agents (potassium permanganate, manganese dioxide) with the release of gaseous chlorine.
- Interaction with ammonia with the formation of thick white smoke, consisting of the smallest crystals of ammonium chloride.
- A qualitative reaction to hydrochloric acid and its salts is its interaction with silver nitrate, which forms a curd precipitate of silver chloride, insoluble in nitric acid.
Receipt
Hydrochloric acid is produced by dissolving hydrogen chloride gas in water. Hydrogen chloride is obtained by burning hydrogen in chlorine, the acid obtained in this way is called synthetic. Hydrochloric acid is also obtained from off-gases - by-product gases generated during various processes, for example, during the chlorination of hydrocarbons. The hydrogen chloride contained in these gases is called off-gas, and the acid thus obtained is called off-gas. In recent decades, the share of off-gas hydrochloric acid in the volume of production has been gradually increasing, displacing the acid obtained by burning hydrogen in chlorine. But hydrochloric acid obtained by burning hydrogen in chlorine contains fewer impurities and is used when high purity is required. In laboratory conditions, a method developed by alchemists is used, which consists in the action of concentrated sulfuric acid on table salt. At temperatures above 550 °C and an excess of table salt, interaction is possible. It is possible to obtain by hydrolysis of chlorides of magnesium, aluminum (hydrated salt is heated). These reactions may not go to completion with the formation of basic chlorides (oxychlorides) of variable composition, for example. Hydrogen chloride is highly soluble in water. So, at 0 °C, 1 volume of water can absorb 507 volumes of HCl, which corresponds to an acid concentration of 45%. However, at room temperature, the solubility of HCl is lower, so 36% hydrochloric acid is usually used in practice.
Application
Industry
- It is used in hydrometallurgy and electroforming (etching, pickling), for cleaning the surface of metals during soldering and tinning, for obtaining chlorides of zinc, manganese, iron, and other metals. In a mixture with surfactants, it is used to clean ceramic and metal products (inhibited acid is needed here) from contamination and disinfection.
- It is registered in the food industry as an acidity regulator (food additive E507). It is used to make seltzer (soda) water.
The medicine
- A natural component of human gastric juice. At a concentration of 0.3-0.5%, usually mixed with the enzyme pepsin, it is administered orally with insufficient acidity.
Features of circulation
Highly concentrated hydrochloric acid is a corrosive substance that causes severe chemical burns if it comes into contact with the skin. Eye contact is especially dangerous. To neutralize burns, a weak alkali solution, usually baking soda, is used. When opening vessels with concentrated hydrochloric acid, hydrogen chloride vapor, attracting moisture from the air, forms a mist that irritates the eyes and respiratory tract of a person. Reacts with strong oxidizing agents (chlorine, manganese dioxide, potassium permanganate) to form toxic chlorine gas. In the Russian Federation, the circulation of hydrochloric acid with a concentration of 15% or more is limited.
