Molar mass of table salt. Salt Formula
Table salt is sodium chloride used as a food additive and food preservative. It is also used in the chemical industry, medicine. It serves as the most important raw material for the production of caustic soda, soda and other substances. The formula for table salt is NaCl.
Formation of an ionic bond between sodium and chlorine
The chemical composition of sodium chloride reflects the conditional formula NaCl, which gives an idea of the equal number of sodium and chlorine atoms. But the substance is formed not by diatomic molecules, but consists of crystals. When an alkali metal interacts with a strong non-metal, each sodium atom gives off more electronegative chlorine. There are sodium cations Na + and anions of the acid residue of hydrochloric acid Cl - . Oppositely charged particles are attracted, forming a substance with an ionic crystal lattice. Small sodium cations are located between large chloride anions. The number of positive particles in the composition of sodium chloride is equal to the number of negative ones, the substance as a whole is neutral.
Chemical formula. Table salt and halite
Salts are complex ionic substances whose names begin with the name of the acid residue. The formula for table salt is NaCl. Geologists call a mineral of this composition “halite”, and sedimentary rock is called “rock salt”. An obsolete chemical term that is often used in industry is "sodium chloride". This substance has been known to people since ancient times, it was once considered "white gold". Modern schoolchildren and students, when reading the equations of reactions involving sodium chloride, call chemical signs ("sodium chloride").
We will carry out simple calculations according to the formula of the substance:
1) Mr (NaCl) \u003d Ar (Na) + Ar (Cl) \u003d 22.99 + 35.45 \u003d 58.44.
The relative is 58.44 (in amu).
2) The molar mass is numerically equal to the molecular weight, but this value has units of g / mol: M (NaCl) \u003d 58.44 g / mol.
3) A 100 g sample of salt contains 60.663 g of chlorine atoms and 39.337 g of sodium.
Physical properties of table salt
Brittle crystals of halite are colorless or white. In nature, there are also deposits of rock salt, painted in gray, yellow or blue. Sometimes the mineral substance has a red tint, which is due to the types and amount of impurities. The hardness of halite is only 2-2.5, the glass leaves a line on its surface.
Other physical parameters of sodium chloride:
- smell - absent;
- taste - salty;
- density - 2.165 g / cm3 (20 ° C);
- melting point - 801 ° C;
- boiling point - 1413 ° C;
- solubility in water - 359 g / l (25 ° C);
Obtaining sodium chloride in the laboratory
When metallic sodium interacts with gaseous chlorine in a test tube, a white substance is formed - sodium chloride NaCl (common salt formula).
Chemistry gives an idea of the different ways to obtain the same compound. Here are some examples:
NaOH (aq.) + HCl \u003d NaCl + H 2 O.
Redox reaction between metal and acid:
2Na + 2HCl \u003d 2NaCl + H 2.
Action of acid on metal oxide: Na 2 O + 2HCl (aq.) = 2NaCl + H 2 O
Displacement of a weak acid from a solution of its salt by a stronger one:
Na 2 CO 3 + 2HCl (aq.) \u003d 2NaCl + H 2 O + CO 2 (gas).
All of these methods are too expensive and complicated to be applied on an industrial scale.
Salt production
Even at the dawn of civilization, people knew that after salting, meat and fish last longer. Transparent, regular-shaped halite crystals were used in some ancient countries instead of money and were worth their weight in gold. The search and development of halite deposits made it possible to meet the growing needs of the population and industry. The most important natural sources of table salt:
- deposits of the mineral halite in different countries;
- water of the seas, oceans and salt lakes;
- layers and crusts of rock salt on the banks of salt water bodies;
- halite crystals on the walls of volcanic craters;
- salt marshes.
In industry, four main methods are used to obtain table salt:
- leaching of halite from the underground layer, evaporation of the resulting brine;
- mining in ;
- evaporation or brine of salt lakes (77% of the mass of dry residue is sodium chloride);
- use of a by-product of desalination of salt water.
Chemical properties of sodium chloride
In its composition, NaCl is a medium salt formed by an alkali and a soluble acid. Sodium chloride is a strong electrolyte. The attraction between ions is so strong that only highly polar solvents can destroy it. In water, substances decompose, cations and anions (Na +, Cl -) are released. Their presence is due to the electrical conductivity, which has a solution of common salt. The formula in this case is written in the same way as for dry matter - NaCl. One of the qualitative reactions to the sodium cation is the yellow coloring of the burner flame. To obtain the result of the experiment, you need to collect a little solid salt on a clean wire loop and add it to the middle part of the flame. The properties of table salt are also associated with the feature of the anion, which consists in a qualitative reaction to the chloride ion. When interacting with silver nitrate in solution, a white precipitate of silver chloride precipitates (photo). Hydrogen chloride is displaced from the salt by stronger acids than hydrochloric: 2NaCl + H 2 SO 4 = Na 2 SO 4 + 2HCl. Under normal conditions, sodium chloride does not undergo hydrolysis.
Areas of application of rock salt
Sodium chloride lowers the melting point of ice, which is why a mixture of salt and sand is used on roads and sidewalks in winter. It absorbs a large amount of impurities, while thawing pollutes rivers and streams. Road salt also accelerates the corrosion process of car bodies and damages trees planted next to roads. In the chemical industry, sodium chloride is used as a raw material for the production of a large group of chemicals:
- of hydrochloric acid;
- metallic sodium;
- gaseous chlorine;
- caustic soda and other compounds.
In addition, table salt is used in the manufacture of soaps and dyes. As a food antiseptic, it is used in canning, pickling mushrooms, fish and vegetables. To combat thyroid disorders in the population, the table salt formula is enriched by adding safe iodine compounds, for example, KIO 3 , KI, NaI. Such supplements support the production of thyroid hormone, prevent the disease of endemic goiter.
The value of sodium chloride for the human body
The formula of table salt, its composition has become vital for human health. Sodium ions are involved in the transmission of nerve impulses. Chlorine anions are necessary for the production of hydrochloric acid in the stomach. But too much salt in food can lead to high blood pressure and increase the risk of developing heart and vascular diseases. In medicine, with a large blood loss, patients are injected with physiological saline. To obtain it, 9 g of sodium chloride is dissolved in one liter of distilled water. The human body needs a continuous supply of this substance with food. Salt is excreted through the excretory organs and skin. The average content of sodium chloride in the human body is approximately 200 g. Europeans consume about 2-6 g of table salt per day, in hot countries this figure is higher due to higher sweating.
The active ingredient in this remedy is sodium chloride . The formula of sodium chloride is NaCl, these are white crystals that quickly dissolve in water. Molar mass 58.44 g/mol. OKPD code - 14.40.1.
Physiological solution (isotonic) is a solution of 0.9%, it contains 9 g of sodium chloride, up to 1 liter of distilled water.
Hypertonic sodium chloride solution is a 10% solution, it contains 100 g of sodium chloride, up to 1 liter of distilled water.
Release form
A solution of sodium chloride 0.9% is produced, which can be contained in ampoules of 5 ml, 10 ml, 20 ml. Ampoules are used to dissolve drugs for injection.
A solution of sodium chloride 0.9% is also produced in bottles of 100, 200, 400 and 1000 ml. Their use in medicine is practiced for external use, intravenous drip infusions, and enemas.
A solution of sodium chloride 10% is contained in vials of 200 and 400 ml.
For the purpose of oral administration, tablets of 0.9 g are produced.
A nasal spray is also produced in 10 ml bottles.
pharmachologic effect
Sodium chloride is a drug that acts as a rehydrating and detoxifying agent. The drug is able to compensate for the lack of sodium in the body, subject to the development of various pathologies. Sodium chloride also increases the amount of fluid that circulates in the vessels.
Such properties of the solution are manifested due to the presence in it chloride ions and sodium ions . They are able to penetrate the cell membrane using various transport mechanisms, in particular the sodium-potassium pump. Sodium plays an important role in the process of signal transmission in neurons, it is also involved in the process of metabolism in the kidneys and in the electrophysiological processes of the human heart.
The pharmacopoeia indicates that sodium chloride maintains a constant pressure in the extracellular fluid and blood plasma. In the normal state of the body, a sufficient amount of this compound enters the body with food. But in pathological conditions, in particular, with vomiting , diarrhea , serious burns there is an increased excretion of these elements from the body. As a result, the body is deficient in chloride and sodium ions, as a result of which the blood becomes thicker, the functions of the nervous system, blood flow, convulsions, spasms of smooth muscle muscles are disturbed.
If an isotonic sodium chloride solution is introduced into the blood in a timely manner, its use contributes to the recovery water-salt balance . But since the osmotic pressure of the solution is similar to the pressure of the blood plasma, it does not stay in the vascular bed for a long time. After administration, it is rapidly excreted from the body. As a result, after 1 hour, no more than half of the injected amount of solution is retained in the vessels. Therefore, in case of blood loss, the solution is not effective enough.
The tool also has plasma-substituting, detoxifying properties.
With the introduction of intravenous hypertonic solution, there is an increase replenishment of the deficiency of chlorine and sodium in the body.
Pharmacokinetics and pharmacodynamics
Excretion from the body occurs mainly through the kidneys. Some sodium is excreted in sweat and feces.
Indications for use
Sodium chloride is a saline solution that is used when the body loses extracellular fluid. Indicated for conditions that lead to fluid restriction:
- dyspepsia in case of poisoning;
- vomit , ;
- extensive burns;
- hyponatremia or hypochloremia in which there is dehydration.
Considering what sodium chloride is, it is used externally to wash wounds, eyes, and nose. The drug is used to moisten dressings, for inhalation, for the face.
The use of NaCl for forced diuresis is shown in cases of poisoning, with internal bleeding (pulmonary, intestinal, gastric).
It is also indicated in the indications for the use of sodium chloride that this is a remedy that is used to dilute and dissolve drugs that are administered parenterally.
Contraindications
The use of the solution is contraindicated in such diseases and conditions:
- hypokalemia , hyperchloremia , hypernatremia ;
- extracellular hyperhydration , ;
- pulmonary edema , cerebral edema ;
- acute left ventricular failure;
- the development of circulatory disorders, in which there is a threat of swelling of the brain and lungs;
- the appointment of large doses of corticosteroids.
Carefully, the solution is prescribed to people who are sick arterial hypertension , peripheral edema, decompensated chronic heart failure, chronic renal failure, preeclampsia , as well as those who have been diagnosed with other conditions in which sodium is retained in the body.
If the solution is used as a dissolving agent for other drugs, existing contraindications should be taken into account.
Side effects
When using sodium chloride, the following conditions may develop:
- hyperhydration ;
- hypokalemia ;
- acidosis .
If the drug is used correctly, the development of side effects is unlikely.
If a 0.9% NaCl solution is used as the base solvent, then the side effects are determined by the properties of the drugs that are diluted with the solution.
If any negative effects appear, you should immediately inform the specialist about it.
Application instruction of Sodium Chloride (Way and dosage)
The instruction for saline solution (isotonic solution) provides for its administration intravenously and subcutaneously.
In most cases, intravenous drip is practiced, for which the sodium chloride dropper is heated to a temperature of 36-38 degrees. The volume that is administered to the patient depends on the condition of the patient, as well as on the amount of fluid that has been lost by the body. It is important to take into account the person's age and weight.
The average daily dose of the drug is 500 ml, the solution is injected at an average rate of 540 ml / h. If there is a strong degree of intoxication, then the maximum amount of medication per day can be 3000 ml. If there is such a need, you can enter a volume of 500 ml at a rate of 70 drops per minute.
Children are given a dose of 20 to 100 ml per day per 1 kg of weight. The dosage depends on body weight, on the age of the child. It should be borne in mind that with prolonged use of this drug, it is necessary to control the level of electrolytes in plasma and urine.
To dilute drugs that need to be administered by drip, 50 to 250 ml of sodium chloride is used per dose of the drug. The determination of the features of the introduction is carried out according to the main drug.
The introduction of a hypertonic solution is carried out intravenously by jet.
If the solution is used to immediately compensate for the deficiency of sodium and chlorine ions, 100 ml of the solution is dripped.
To conduct a rectal enema to induce defecation, 100 ml of a 5% solution is administered; 3000 ml of an isotonic solution can also be administered throughout the day.
The use of a hypertonic enema is slowly indicated for renal and cardiac edema, increased and in case of hypertension, it is carried out slowly, 10-30 ml is injected. You can not carry out such an enema with erosion of the colon and inflammatory processes.
Purulent wounds with a solution are carried out in accordance with the scheme prescribed by the doctor. NaCl compresses are applied directly to a wound or other skin lesion. Such a compress contributes to the separation of pus, the death of pathogenic microorganisms.
nasal spray instilled into the nasal cavity after its cleansing. For adult patients, two drops are instilled into each nostril, for children - 1 drop. It is used both for treatment and for prevention, for which the solution is dripped for about 20 days.
Sodium chloride for inhalation used for colds. To do this, the solution is mixed with bronchodilators. Inhalation is carried out for ten minutes three times a day.
If necessary, saline can be prepared at home. To do this, a full teaspoon of salt should be mixed in one liter of boiled water. If it is necessary to prepare a certain amount of solution, for example, with salt weighing 50 g, appropriate measurements should be made. Such a solution can be applied topically, used for enemas, rinses, inhalations. However, in no case should such a solution be administered intravenously or used to treat open wounds or eyes.
Overdose
In case of an overdose, the patient may feel nausea, suffer from vomiting and diarrhea, he may develop abdominal pain, fever, heart palpitations. Also, with an overdose, indicators may increase, pulmonary edema and peripheral edema may develop, kidney failure , muscle cramps , weakness , generalized convulsions , coma . With excessive administration of the solution, it may develop hypernatremia .
Excessive intake may result in hyperchloric acidosis .
If sodium chloride is used to dissolve drugs, then the overdose is mainly associated with the properties of those drugs that are diluted.
In case of inadvertent NaCl overdose, it is important to stop this process and evaluate if the patient has worse symptoms. Symptomatic treatment is practiced.
Interaction
NaCl is compatible with most drugs. It is this property that determines the use of a solution for diluting and dissolving a number of drugs.
When diluting and dissolving, it is necessary to control the compatibility of drugs visually, determining whether a precipitate appears in the process, whether the color changes, etc.
When administered concomitantly with corticosteroids it is important to constantly monitor the content of electrolytes in the blood.
When taken concomitantly, the hypotensive effect decreases and Spirapril .
Sodium Chloride is incompatible with a leukopoiesis stimulator Filgrastim , as well as with a polypeptide antibiotic Polymyxin B .
There is evidence that isotonic saline increases the bioavailability of drugs.
When diluted with a solution of powdered antibiotics, they are completely absorbed by the body.
Terms of sale
It is sold in pharmacies by prescription. If necessary, use the drug to dilute other drugs, etc. write out a prescription in Latin.
Storage conditions
Store the powder, tablets and solution in a dry place, in a well-closed container, while the temperature should not exceed 25 degrees Celsius. It is important to keep the drug out of the reach of children. If the packaging is airtight, then freezing does not affect the properties of the drug.
Best before date
There are no restrictions on the storage of powder and tablets. A solution in 0.9% ampoules can be stored for 5 years; solution in vials 0.9% - one year, solution in vials 10% - 2 years. Cannot be used after the storage period has expired.
special instructions
If an infusion is carried out, the patient's condition, in particular, plasma electrolytes, must be carefully monitored. It should be borne in mind that in children, due to the immaturity of kidney function, it is possible to slow down sodium excretion . It is important to determine its plasma concentration before repeated infusions.
It is important to control the state of the solution before its introduction. The solution must be transparent, the packaging must be intact. Only a qualified specialist can use the solution for intravenous administration.
Dissolve any preparations with Sodium Chloride should only be a specialist who can competently assess whether the resulting solution is suitable for administration. It is important to strictly adhere to all the rules of antiseptics. The introduction of any solution should be carried out immediately after its preparation.
The result of a series of chemical reactions involving sodium chloride is the formation of chlorine. Electrolysis of sodium chloride melt in industry is a method for producing chlorine. If a solution of Sodium Chloride is electrolyzed, chlorine is also obtained as a result. If crystalline Sodium Chloride is treated with concentrated sulfuric acid, the result is hydrogen chloride . and sodium hydroxide can be obtained through a chain of chemical reactions. A qualitative reaction to the chloride ion is a reaction with.
Analogues
Coincidence in the ATX code of the 4th level:
Different manufacturers of medicines may produce a solution under a separate name. These are drugs Sodium Chloride Brown , Sodium chloride Bufus , Rizosin , Salin Sodium Chloride Cinco and etc.
Preparations containing sodium chloride are also produced. These are combined saline solutions + sodium chloride, etc.
children
It is applied according to the instructions and under the careful supervision of specialists. The immaturity of renal function in children should be taken into account, therefore, repeated administration is carried out only after an accurate determination of the level of sodium in the plasma.
During pregnancy and lactation
During pregnancy, a dropper with sodium chloride can only be used in pathological conditions. This is toxicosis in the middle or severe stage, as well. Healthy women receive sodium chloride with food, and its excess can lead to the development of edema.
Reviews
Most of the reviews are positive, as users write about this tool as a useful drug. There are especially many reviews about the nasal spray, which, according to patients, is a good tool for both prevention and treatment of the common cold. The tool effectively moisturizes the nasal mucosa and promotes healing.
Price of Sodium Chloride, where to buy
The price of a saline solution in ampoules of 5 ml is an average of 30 rubles per 10 pcs. Buy sodium chloride 0.9% in a bottle of 200 ml is an average of 30-40 rubles per bottle.
- Internet pharmacies in Russia Russia
- Internet pharmacies of Ukraine Ukraine
- Internet pharmacies in Kazakhstan Kazakhstan
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Structural formula
True, empirical, or gross formula: ClNa
Chemical composition of sodium chloride
Molecular weight: 58.443
Sodium chloride or sodium chloride (NaCl) - sodium hydrochloric acid. Known in everyday life under the name of table salt, the main component of which is. Sodium chloride is found in significant amounts in sea water, giving it a salty taste. It occurs naturally as the mineral halite (rock salt). Pure sodium chloride is a colorless crystal, but with various impurities, its color can take on a blue, purple, pink, yellow or gray tint.
Finding in nature and production
In nature, sodium chloride occurs in the form of the mineral halite, which forms deposits of rock salt among sedimentary rocks, layers and lenses on the shores of salt lakes and estuaries, salt crusts in salt marshes and on the walls of volcano craters and in solfataras. A huge amount of sodium chloride is dissolved in sea water. The world ocean contains 4 × 10 15 tons of NaCl, that is, from every thousand tons of sea water, an average of 1.3 tons of sodium chloride can be obtained. Traces of NaCl are permanently present in the atmosphere as a result of the evaporation of seawater spray. In clouds at a height of one and a half kilometers, 30% of droplets larger than 10 microns in size contain NaCl. It is also found in snow crystals. It is most likely that the first acquaintance of man with salt occurred in the lagoons of warm seas or in salt lakes, where in shallow water, salt water evaporated intensively under the influence of high temperature and wind, and salt accumulated in the sediment. According to the figurative expression of Pythagoras, "salt was born of noble parents: the sun and the sea."
Halite
In nature, sodium chloride is most commonly found as the mineral halite. It has a face-centered cubic lattice and contains 39.34% Na, 60.66% Cl. Other chemical elements included in the impurities are: Br, N, H, Mn, Cu, Ga, As, I, Ag, Ba, Tl, Pb, K, Ca, S, O. Density 2.1-2, 2 g/cm³ and Mohs hardness 2. Colorless transparent mineral with a vitreous luster. A common mineral in salt-bearing strata. It is formed during sedimentation in closed reservoirs, and also as a product of a surge on the walls of volcanic craters. It forms layers in sedimentary rocks of lagoonal and marine facies, stock-like bodies in salt domes, and the like.
Rock salt
Rock salt is a sedimentary rock from the group of evaporites, consisting of more than 90% halite. Halite is also often referred to as rock salt. This sedimentary rock can be colorless or snow-white, but more often it is colored by impurities of clays, talc (gray), iron oxides and hydroxides (yellow, orange, pink, red), bitumen (brown). Rock salt contains chlorides and sulfates of sodium, potassium, magnesium and calcium, bromides, iodides, borates, gypsum, impurities of carbonate-clay material, dolomite, ankerite, magnesite, bitumen and so on. According to the conditions of formation of deposits, rock salt is divided into the following types:
- brines of modern salt basins
- saline underground water
- deposits of mineral salts of modern salt basins
- fossil deposits (important for industry).
Sea salt
Sea salt is a mixture of salts (chlorides, carbonates, sulfates, etc.) formed by the complete evaporation of sea water. The average salt content in sea water is:
When seawater evaporates at a temperature of +20 to +35 °C, the least soluble salts, calcium and magnesium carbonates and calcium sulfate, first crystallize in the sediment. Then more soluble sodium and magnesium sulfates, sodium, potassium and magnesium chlorides precipitate, and after them - potassium and magnesium sulfates. The sequence of crystallization of salts and the composition of the precipitate may vary somewhat depending on temperature, evaporation rate and other conditions. In industry, sea salt is obtained from sea water, mainly by conventional evaporation. It differs from rock salt by a significantly higher content of other chemical salts, minerals and various trace elements, primarily iodine, potassium, magnesium and manganese. Accordingly, it differs from sodium chloride in taste - a bitter-salty taste is given to it by magnesium salts. It is used in medicine: in the treatment of skin diseases such as psoriasis. As a medicinal substance in the pharmacy and regular trade network, salt from the Dead Sea is a common product. In a purified form, this type of salt is also offered in the grocery trade network - as a natural and iodine-rich food.deposits
Rock salt deposits are found in all geological systems. The most important of them are concentrated in the Cambrian, Devonian, Permian and Tertiary deposits. Rock salt makes up powerful reservoir deposits and cores of vaulted structures (salt domes and stocks), forms interlayers, lenses, nests and inclusions in other rocks. Among the lake deposits in Russia, the largest are Eltonskoye, Baskunchak in the Caspian Sea, Kuchukskoye Lake, Kulundinskoye Lake, Ebeyty and other lakes in Western Siberia.
Production
In ancient times, the technology of salt extraction consisted in the fact that salt brine (solution) was pulled out by a horse drive from mines, which were called "wells" or "windows", and were deep enough - 60-90 m. The extracted salt solution was poured into a special reservoir - created , from where it flowed through the holes into the lower reservoir, and was fed into the wooden towers by a system of gutters. There it was poured into large vats, on which the salt was boiled. In Russia, the Pomors boiled salt on the coast of the White Sea and called it a sailor. In 1137, Prince Svyatoslav of Novgorod determined a tax on salt pans:
... on the sea from the crap and from the salga in the belly ...
White Sea salt, called "moryanka", was traded throughout the Russian Empire until the beginning of the 20th century, when it was replaced by cheaper Volga salt. Modern extraction of sodium chloride is mechanized and automated. Salt is mass-produced by evaporating sea water (then called sea salt) or brine from other resources such as salt springs and salt lakes, as well as by mining salt mines and extracting rock salt. The extraction of sodium chloride from sea water requires a hot climate with low air humidity, the presence of significant low-lying areas that lie below sea level or are flooded by the tide, poor soil permeability of the evaporation pools, low precipitation during the season of active evaporation, and the absence of the influence of fresh river water. and the availability of a developed transport infrastructure. World salt production in 2009 is estimated at 260 million tons. The world's largest producers are China (60.0 Mt), USA (46.0 Mt), Germany (16.5 Mt), India (15.8 Mt) and Canada (14 Mt).
Application
In the food industry and culinary
In the food industry and cooking, sodium chloride is used, the purity of which must be at least 97%. It is used as a flavoring agent and for food preservation. Such sodium chloride has the trade name table salt, sometimes the names food, table salt are also used, as well as the specification of the name depending on its origin - stone, sea, and according to the composition of additives - iodized, fluorinated, etc. Such salt is a crystalline bulk product with a salty taste without aftertaste, odorless (except for iodized salt), in which foreign impurities not related to the salt extraction method are not allowed. In addition to sodium chloride, table salt contains a small amount of calcium, magnesium, and potassium salts, which make it hygroscopic and hard. The less these impurities in the salt, the higher its quality. There are varieties: extra, highest, first and second. Mass fraction of sodium chloride in varieties,%:
- extra - not less than 99.5;
- the highest - 98.2;
- the first - 97.5;
- the second - 97.0.
In medicine
An isotonic solution of sodium chloride in water (0.9%) is used as a detoxifying agent, to correct the state of body systems in case of dehydration, like other drugs. Hypertonic solutions (10% solution) are used as an auxiliary osmotic diuretic in cerebral edema, to increase pressure during bleeding, in conditions characterized by a deficiency of sodium and chlorine ions, in case of poisoning with silver nitrate, for the treatment of purulent wounds (locally). In ophthalmology, as a topical agent, sodium chloride solution has a decongestant effect.
In public utilities. Technical salt
In winter, sodium chloride mixed with other salts, sand or clay - the so-called technical salt - is used as antifreeze against ice. Sidewalks are sprinkled with it, although this negatively affects leather shoes and the technical condition of vehicles due to corrosive processes.
Regeneration of Na-cationite filters
Na-cationite filters are widely used in water softening plants of all capacities in water treatment. Cationic material in modern water treatment plants are mainly glauconite, polymeric ion-exchange resins and sulfonated coals. Sulfocationic ion-exchange resins are the most common. Regeneration of Na-cationite filters is carried out with a 6-10% sodium chloride solution, as a result, the cationite is converted into the Na-form and regenerated. The reactions follow the equations: CaR 2 + 2NaCl → 2NaR + CaCl 2 MgR 2 + 2NaCl → 2NaR + MgCl 2
Chemical industry
Salt, along with coal, limestone and sulfur, forms the "big four" mineral products, which are the most important for the chemical industry. Soda, chlorine, hydrochloric acid, sodium hydroxide, sodium sulfate and metallic sodium are obtained from it. In addition, salt is also used for the industrial production of sodium chlorate, which is easily soluble in water, which is a weed killer. The overall reaction equation for the electrolysis of a hot solution of sodium chloride: NaCl + 3H 2 O → NaClO 3 + 3H 2
Physical and physico-chemical properties
Melting point +800.8 °C, boiling point +1465 °C. Moderately soluble in water, solubility depends little on temperature: the solubility coefficient of NaCl (in grams per 100 g of water) is 35.9 at +21 °C and 38.1 at +80 °C. The solubility of sodium chloride is significantly reduced in the presence of hydrogen chloride, sodium hydroxide, metal chloride salts. Dissolves in liquid ammonia, enters into exchange reactions. Pure sodium chloride is not hygroscopic. However, salt is often contaminated with impurities (mainly Ca 2+, Mg 2+ and SO 2- 4 ions), and such salt becomes damp in air. NaCl · 2H 2 O crystalline hydrate can be isolated at temperatures below +0.15 °C. A mixture of crushed ice with fine sodium chloride powder is an effective coolant. Thus, a mixture of 30 g of NaCl per 100 g of ice is cooled to a temperature of −20 °C. This is because an aqueous solution of salt freezes at temperatures below 0 °C. Ice, which has a temperature of about 0 ° C, melts in such a solution, absorbing the heat of the environment.
Dielectric constant of NaCl - 6.3Density and concentration of NaCl aqueous solutions
| Concentration, % | Concentration, g/l | Density, g/ml |
|---|---|---|
| 1 | 10,05 | 1,005 |
| 2 | 20,25 | 1,012 |
| 4 | 41,07 | 1,027 |
| 6 | 62,47 | 1,041 |
| 8 | 84,47 | 1,056 |
| 10 | 107,1 | 1,071 |
| 12 | 130,2 | 1,086 |
| 14 | 154,1 | 1,101 |
| 16 | 178,5 | 1,116 |
| 18 | 203,7 | 1,132 |
| 20 | 229,5 | 1,148 |
| 22 | 256 | 1,164 |
| 24 | 283,2 | 1,18 |
| 26 | 311,2 | 1,197 |
Structure
Sodium chloride forms colorless cubic crystals, space group Fm3m, cell parameters a = 0.563874 nm, d = 2.17 g/cm 3 . Each of the Cl - ions is surrounded by six Na + ions in an octahedral configuration, and vice versa. If we mentally discard, for example, Na + ions, then a densely packed cubic structure of Cl - ions remains, called the face-centered cubic lattice. Na + ions also form a densely packed cubic lattice. Thus, the crystal consists of two sublattices shifted relative to each other by a half-cycle. The same lattice is characteristic of many other minerals.
In the crystal lattice between atoms, the ionic chemical bond predominates, which is a consequence of the action of the electrostatic interaction of oppositely charged ions.
State educational institution
Higher professional education
"Perm State Pharmaceutical Academy
Federal Agency for Health and Social Development
Russian Federation"
Department of Analytical Chemistry
Course work:
Sodium chloride.
Completed:
student of group 21
Sennikov Anton
Checked:
Kolotova
Nina Vasilievna
Perm, 2010
Analytical reactions of sodium cation 5
Analytical reactions of chloride ion 5
Argentometry 6
Complexometry 6
General information 3
Getting 4
Qualitative analysis 5
Quantitative analysis 6
Application 7
References 8
General information.
Chlorié d oń tria- chemical compound NaCl, sodium salt of hydrochloric acid, sodium chloride.
Chloride sodium is known in everyday life under the name table salt, of which it is the main component. Sodium chloride is found in significant amounts in sea water, creating it salty taste. Occurs naturally as a mineral halite(rock salt).
Pure sodium chloride has the appearance of colorless crystals. But with various impurities, its color can take on: blue, purple, pink, yellow or gray.
Sodium chloride forms crystals with cubic symmetry. Larger chlorine ions form a dense cubic packing, in the free nodes of which (at the vertices of the regular octahedron) are sodium ions.
It is moderately soluble in water, the solubility depends little on temperature: the solubility coefficient of NaCl (in g per 100 g of water) is 35.9 at 21 ° C and 38.1 at 80 ° C. The solubility of sodium chloride is significantly reduced in the presence of hydrogen chloride, sodium hydroxide , salts - metal chlorides. It dissolves in liquid ammonia, enters into exchange reactions.
Systematic name: sodium chloride / Sodium chloride
Chemical formula: NaCl
Molar mass: 58.44277 g/mol
Physical properties:
Density: 2.165 g/cm3
Thermal properties:
Melting temperature 800.8°C
Boiling temperature 1465°C
Chemical properties:
Solubility in water 35.9 g/100 ml
Receipt.
The first way to obtain sodium was the reduction reaction sodium carbonate coal when heating a close mixture of these substances in an iron container to 1000 ° C:
Na 2 CO 3 + 2C \u003d 2Na + 3CO
Then there was another way to get sodium - electrolysis melt caustic soda or sodium chloride.
3.1. Analytical reactions for the sodium cation.
Qualitative analysis.
1) With dioxouranium (VI) zinc acetate with the formation of a yellow crystalline precipitate or yellow crystals of tatra- and octahedral shape:
NaCl + Zn(UO 2) 3 (CH 3 COO) 8 + CH 3 COOH + 9H 2 O ↔
↔ NaZn(UO 2) 3 (CH 3 COO) 9 x 9H 2 O↓ + HCl
2) Coloring the colorless burner flame yellow;
3) Reaction with potassium hexahydroxoantibate (V) with the formation of a white crystalline precipitate, soluble in alkalis:
NaCl + K ↔ Na↓ + KCl
In an acidic environment, the reagent is destroyed with the formation of a white amorphous precipitate of metaantimony acid HSbO 3:
K + HCl ↔ KCl + H 3 SbO 4 + 2H 2 O
H 3 SbO 4 ↔ HSbO 3 ↓ + H 2 O
3.2. Analytical reactions for chloride ion.
With a group reagent - a solution of AgNO 3:
Methodology: To 2 drops of a solution containing chloride ions, add 1 drop of diluted HNO 3 and 3 drops of AgNO 3 solution. The observed white cheesy precipitate is soluble in NH 4 OH and a saturated solution of (NH 4) 2 CO 3 .
The Cl solution is divided into 2 parts: concentrated HNO 3 is added to one until the medium is acidic, and concentrated KJ solution is added to the other. Precipitation or cloudiness of the solution is observed:
Cl + 2HNO 3 ↔ AgCl ↓ + 2 NH 4 NO 3
Cl + KJ + 2H 2 O ↔ AgJ ↓ + KCl + 2NH 4 OH
Quantitative analysis.
4.1. Argentometry.
Standardization of a 0.05 M silver nitrate solution with a standard sodium chloride solution (pipetting method).
NaCl + AgNO 3 → AgCl↓ + NaNO 3
at the end point of the titration: K 2 CrO 4 + 2AgNO 3 → Ag 2 CrO 4 ↓ + 2KNO 3
M(NaCl) = 58.44 g/mol
M (AgNO 3) \u003d 169.87 g / mol
Methodology: An aliquot of the prepared standard sodium chloride solution is placed in a titration flask, diluted with distilled water twice, two drops of potassium chromate solution are added and titrated with silver nitrate solution until the precipitate turns orange-yellow.
4.2. Complexometry.
Standardization of 0.01 M mercury perchlorate solution against sodium chloride standard solution (pipetting method)
2NaCl + Hg(ClO 4) 2 ↔ HgCl 2 + 2 NaClO 4
M (NaCl) = 58.44 g/mol
Methodology: The exact volume of a standard sodium chloride solution is placed in a titration flask, 4 drops of diluted nitric acid (1:4), 4 drops of 4 drops of an alcoholic saturated solution of diphenylcarbazone are added and titrated with 0.01 M mercury perchlorate solution until the solution turns pinkish-violet.
5. Application.
If 9 grams of salt are dissolved in 1 liter of water, then its concentration in the resulting solution will be the same as in body fluids and tissues (0.9%). This concentration is called isotonic. A higher content of sodium chloride in solutions acts as an antimicrobial, stops the processes of fermentation and decay. This is the basis for its use for salting (preserving) meat and vegetables.
When taken orally salt enhances the secretion of digestive juices, activates the contraction of the stomach and intestines, thins mucus, improves absorption in the gastrointestinal tract. Poisonous in large doses especially for chickens, pigs, dogs and cats. Assign inside as a flavoring and fodder substance that improves digestion in the form of a powder mixed with food or in the form of salt-lick.
6. List of references.
Klyuchinov N.G. "Inorganic synthesis", Moscow, 1988;
Lurie Yu.Yu. "Handbook of Analytical Chemistry", Moscow, 1979;
Methodical manual on analytical chemistry. "Instrumental Methods of Analysis", Perm, 2004;
Methodical manual on analytical chemistry. "Qualitative chemical analysis", Perm, 2003;
Methodical manual on analytical chemistry. "Quantitative chemical analysis", Perm, 2004;
Rabinovich V.A., Khavin Z.Ya. "Brief chemical reference book", Leningrad, Chemistry, 1977;
Thomas C.F. "Anhydrous synthesis in organic chemistry" (translated from English), Moscow, 1949;
Kharitonov Yu.Ya. "Analytical Chemistry", in 2 books, Moscow, 2001.
