Salts: classification and chemical properties. What is salt? Formula, properties of salt (chemistry)

Salts are called complex substances, whose molecules consist of metal atoms and acidic residues (sometimes may contain hydrogen). For example, NaCl is sodium chloride, CaSO 4 is calcium sulfate, etc.

Practically all salts are ionic compounds, Therefore, in salts, ions of acidic residues and metal ions are bound together:

Na + Cl – – sodium chloride

Ca 2+ SO 4 2– – calcium sulfate, etc.

A salt is the product of partial or complete substitution of a metal for the hydrogen atoms of an acid. Hence they distinguish the following types salts:

1. Medium salts– all hydrogen atoms in the acid are replaced by a metal: Na 2 CO 3, KNO 3, etc.

2. Acid salts– not all hydrogen atoms in the acid are replaced by a metal. Of course, acid salts can only form di- or polybasic acids. Monobasic acids cannot produce acidic salts: NaHCO 3, NaH 2 PO 4, etc. d.

3. Double salts– the hydrogen atoms of a di- or polybasic acid are replaced not by one metal, but by two different ones: NaKCO 3, KAl(SO 4) 2, etc.

4. Basic salts can be considered as products of incomplete, or partial, substitution of hydroxyl groups of bases with acidic residues: Al(OH)SO 4, Zn(OH)Cl, etc.

According to international nomenclature, the name of the salt of each acid comes from the Latin name of the element. For example, salts of sulfuric acid are called sulfates: CaSO 4 - calcium sulfate, Mg SO 4 - magnesium sulfate, etc.; salt of hydrochloric acid are called chlorides: NaCl - sodium chloride, ZnCI 2 - zinc chloride, etc.

The particle “bi” or “hydro” is added to the name of salts of dibasic acids: Mg(HCl 3) 2 – magnesium bicarbonate or bicarbonate.

Provided that in a tribasic acid only one hydrogen atom is replaced by a metal, then the prefix “dihydro” is added: NaH 2 PO 4 - sodium dihydrogen phosphate.

Salts are solid substances with very different solubility in water.

Chemical properties of salts

The chemical properties of salts are determined by the properties of the cations and anions that are part of them.

1. Some salts decompose when heated:

CaCO 3 = CaO + CO 2

2. Interact with acids with the formation of a new salt and a new acid. To carry out this reaction, it is necessary that the acid be stronger than the salt that is affected by the acid:

2NaCl + H 2 SO 4 → Na 2 SO 4 + 2HCl.

3. Interact with bases, forming a new salt and a new base:

Ba(OH) 2 + MgSO 4 → BaSO 4 ↓ + Mg(OH) 2.

4. Interact with each other with the formation of new salts:

NaCl + AgNO 3 → AgCl + NaNO 3 .

5. Interact with metals, which are in the range of activity to the metal that is part of the salt:

Fe + CuSO 4 → FeSO 4 + Cu↓.

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What are salts?

Salts are complex substances that consist of metal atoms and acidic residues. In some cases, salts may contain hydrogen.

If we carefully examine this definition, we will notice that in their composition salts are somewhat similar to acids, the only difference being that acids consist of hydrogen atoms, and salts contain metal ions. It follows from this that salts are products of the replacement of hydrogen atoms in an acid with metal ions. So, for example, if we take the table salt NaCl, known to everyone, then it can be considered as a product of the replacement of hydrogen in hydrochloric acid HC1 with a sodium ion.

But there are also exceptions. Take, for example, ammonium salts; they contain acidic residues with an NH4+ particle, and not with metal atoms.

Types of salts

Now let's take a closer look at the classification of salts.

Classification:

Acid salts are those in which the hydrogen atoms in the acid are partially replaced by metal atoms. They can be obtained by neutralizing a base with excess acid.
Medium salts, or as they are also called normal salts, include those salts in which all hydrogen atoms in the acid molecules are replaced by metal atoms, for example, such as Na2CO3, KNO3, etc.
Basic salts include those in which the hydroxyl groups of bases are incompletely or partially replaced by acidic residues, such as Al(OH)SO4, Zn(OH)Cl, etc.
Double salts contain two different cations, which are obtained by crystallization from a mixed solution of salts with different cations, but the same anions.
But mixed salts include those that contain two different anions.

There are also complex salts, which contain a complex cation or a complex anion.

Physical properties of salts

We already know that salts are solids, but you should know that they have different solubility in water.

Soluble (P),
- insoluble (N)
- sparingly soluble (M).

Nomenclature of salts

To determine the degree of solubility of salts, you can refer to the table of solubility of acids, bases and salts in water.

As a rule, all salt names consist of the names of the anion, which is represented in nominative case and a cation, which is in the genitive case.

For example: Na2SO4 - sodium sulfate (I.p.).

In addition, for metals, a variable oxidation state is indicated in parentheses.

Let's take for example:

FeSO4 - iron (II) sulfate.

You should also know that there is an international nomenclature for the name of the salts of each acid, depending on the Latin name of the element. For example, salts of sulfuric acid are called sulfates. For example, CaSO4 is called calcium sulfate. But chlorides are called salts of hydrochloric acid. For example, NaCl, which is familiar to all of us, is called sodium chloride.

If they are salts of dibasic acids, then the particle “bi” or “hydro” is added to their name.

For example: Mg(HCl3)2 – will sound like magnesium bicarbonate or bicarbonate.

If in a tribasic acid one of the hydrogen atoms is replaced by a metal, then the prefix “dihydro” should also be added and we get:

NaH2PO4 – sodium dihydrogen phosphate.

Chemical properties of salts

Now let's move on to considering the chemical properties of salts. The fact is that they are determined by the properties of the cations and anions that are part of them.

The importance of salt for the human body

There have long been discussions in society about the dangers and benefits of salt that it has on the human body. But no matter what point of view opponents adhere to, you should know that table salt is a mineral natural substance, which is vital for our body.

You should also know that with a chronic lack of sodium chloride in the body, death can occur. After all, if we remember our biology lessons, we know that the human body is seventy percent water. And thanks to salt, the processes of regulating and maintaining water balance in our body occur. Therefore, it is impossible to exclude the use of salt under any circumstances. Of course, excessive consumption of salt will also not lead to anything good. And here the conclusion arises that everything should be in moderation, since its deficiency, as well as its excess, can lead to an imbalance in our diet.

Application of salts

Salts have found their use, as in production purposes, and in our Everyday life. Now let's take a closer look and find out where and what salts are most often used.

Salts of hydrochloric acid

The most commonly used salts of this type are sodium chloride and potassium chloride. The table salt that we eat is obtained from sea and lake water, as well as from salt mines. And if we eat sodium chloride, then in industry it is used to produce chlorine and soda. But potassium chloride is indispensable in agriculture. It is used as potassium fertilizer.

Sulfuric acid salts

As for the salts of sulfuric acid, they found wide application in medicine and construction. It is used to make gypsum.

Salts nitric acid

Salts of nitric acid, or nitrates as they are also called, are used in agriculture as fertilizers. The most significant among these salts are sodium nitrate, potassium nitrate, calcium nitrate and ammonium nitrate. They are also called saltpeter.

Orthophosphates

Among orthophosphates, one of the most important is calcium orthophosphate. This salt forms the basis of such minerals as phosphorites and apatites, which are necessary in the manufacture of phosphate fertilizers.

Carbonic acid salts

Carbonic acid salts or calcium carbonate can be found in nature in the form of chalk, limestone and marble. It is used to make lime. But potassium carbonate is used as a component of raw materials in the production of glass and soap.

Of course, you know a lot of interesting things about salt, but there are also facts that you would hardly have guessed.

You probably know the fact that in Rus' it was customary to greet guests with bread and salt, but you were angry that they even paid a tax for salt.

Do you know that there were times when salt was more valuable than gold? In ancient times, Roman soldiers were even paid in salt. And the most dear and important guests were presented with a handful of salt as a sign of respect.

Do you know what the concept of “ wage" comes from English word salary.

It turns out that table salt can be used for medical purposes, as it is an excellent antiseptic and has wound-healing and bactericidal properties. After all, probably each of you observed, while at sea, that wounds on the skin and calluses in the salty sea water heal much faster.

Do you know why it is customary to sprinkle the paths with salt in winter when there is ice? It turns out that if salt is poured onto ice, the ice turns into water, since its crystallization temperature will decrease by 1-3 degrees.

Do you know how much salt a person consumes during the year? It turns out that you and I eat about eight kilograms of salt per year.

It turns out that people living in hot countries need to consume four times more salt than those living in cold countries. climatic zones, because during the heat it is released a large number of sweat, and with it salts are removed from the body.

Definition salts within the framework of dissociation theory. Salts are usually divided into three groups: medium, sour and basic. In medium salts, all hydrogen atoms of the corresponding acid are replaced by metal atoms, in acidic salts they are only partially replaced, in basic salts of the OH group of the corresponding base they are partially replaced by acidic residues.

There are also some other types of salts, such as double salts, which contain two different cations and one anion: CaCO 3 MgCO 3 (dolomite), KCl NaCl (sylvinite), KAl(SO 4) 2 (potassium alum); mixed salts, which contain one cation and two different anions: CaOCl 2 (or Ca(OCl)Cl); complex salts, which includes complex ion, consisting of a central atom bonded to several ligands: K 4 (yellow blood salt), K 3 (red blood salt), Na, Cl; hydrate salts(crystalline hydrates), which contain molecules water of crystallization: CuSO 4 5H 2 O (copper sulfate), Na 2 SO 4 10H 2 O (Glauber's salt).

Name of salts formed from the name of the anion followed by the name of the cation.

For salts of oxygen-free acids, the suffix is added to the name of the non-metal id, for example, sodium chloride NaCl, iron sulfide (H) FeS, etc.

When naming salts of oxygen-containing acids, the ending is added to the Latin root of the name of the element in the case of higher oxidation states — am, in the case of lower oxidation states, the end -it. In the names of some acids, the prefix is used to denote the lower oxidation states of a non-metal hypo-, for salts of perchloric and permanganic acids use the prefix per-, for example: calcium carbonate CaCO 3, iron(III) sulfate Fe 2 (SO 4) 3, iron(II) sulfite FeSO 3, potassium hypochlorite KOCl, potassium chlorite KOCl 2, potassium chlorate KOCl 3, potassium perchlorate KOCl 4, potassium permanganate KMnO 4, potassium dichromate K 2 Cr 2 O 7 .

Acid and basic salts can be considered as a product of incomplete conversion of acids and bases. According to international nomenclature, the hydrogen atom that is part of an acid salt is designated by the prefix hydro-, group OH - prefix hydroxy NaHS - sodium hydrosulfide, NaHSO 3 - sodium hydrosulfite, Mg(OH)Cl - magnesium hydroxychloride, Al(OH) 2 Cl - aluminum dihydroxychloride.

In the names of complex ions, the ligands are first indicated, followed by the name of the metal, indicating the corresponding oxidation state (in Roman numerals in parentheses). In the names of complex cations, Russian names of metals are used, for example: Cl 2 - tetraammine copper (P) chloride, 2 SO 4 - diammine silver sulfate (1). The names of complex anions use the Latin names of metals with the suffix -at, for example: K[Al(OH) 4 ] - potassium tetrahydroxyaluminate, Na - sodium tetrahydroxychromate, K 4 - potassium hexacyanoferrate(H).

Names of hydration salts (crystal hydrates) are formed in two ways. You can use the naming system for complex cations described above; for example, copper sulfate SO 4 H 2 0 (or CuSO 4 5H 2 O) can be called tetraaquacopper(P) sulfate. However, for the most well-known hydration salts, most often the number of water molecules (degree of hydration) is indicated by a numerical prefix to the word "hydrate", for example: CuSO 4 5H 2 O - copper(I) sulfate pentahydrate, Na 2 SO 4 10H 2 O - sodium sulfate decahydrate, CaCl 2 2H 2 O - calcium chloride dihydrate.

Salt solubility

Based on their solubility in water, salts are divided into soluble (P), insoluble (H) and slightly soluble (M). To determine the solubility of salts, use the table of solubility of acids, bases and salts in water. If you don’t have a table at hand, you can use the rules. They are easy to remember.

1. All salts of nitric acid - nitrates - are soluble.

2. All salts of hydrochloric acid are soluble - chlorides, except AgCl (H), PbCl 2 (M).

3. All salts of sulfuric acid are soluble - sulfates, except BaSO 4 (H), PbSO 4 (H).

4. Sodium and potassium salts are soluble.

5. All phosphates, carbonates, silicates and sulfides are insoluble, except Na salts + and K + .

Of all chemical compounds salts are the most numerous class of substances. These are solid substances, they differ from each other in color and solubility in water. IN early XIX V. Swedish chemist I. Berzelius formulated the definition of salts as products of reactions of acids with bases or compounds obtained by replacing hydrogen atoms in an acid with a metal. On this basis, salts are distinguished between medium, acidic and basic. Medium, or normal, salts are the products of complete replacement of hydrogen atoms in an acid with a metal.

For example:

Na 2 CO 3 - sodium carbonate;

CuSO 4 - copper (II) sulfate, etc.

Such salts dissociate into metal cations and anions of the acid residue:

Na 2 CO 3 = 2Na + + CO 2 -

Acid salts are products of incomplete replacement of hydrogen atoms in an acid with a metal. Acid salts include, for example, baking soda NaHCO 3, which consists of the metal cation Na + and the acidic single-charge residue HCO 3 -. For an acidic calcium salt, the formula is written as follows: Ca(HCO 3) 2. The names of these salts are composed of the names of the middle salts with the addition of the prefix hydro- , For example:

Mg(HSO 4) 2 - magnesium hydrogen sulfate.

Acid salts are dissociated as follows:

NaHCO 3 = Na + + HCO 3 -
Mg(HSO 4) 2 = Mg 2+ + 2HSO 4 -

Basic salts are products of incomplete substitution of hydroxo groups in the base with an acid residue. For example, such salts include the famous malachite (CuOH) 2 CO 3, which you read about in the works of P. Bazhov. It consists of two main cations CuOH + and a doubly charged acid residue anion CO 3 2- . The CuOH + cation has a charge of +1, so in the molecule two such cations and one doubly charged CO 3 2- anion are combined into an electrically neutral salt.

The names of such salts will be the same as those of normal salts, but with the addition of the prefix hydroxo-, (CuOH) 2 CO 3 - copper (II) hydroxycarbonate or AlOHCl 2 - aluminum hydroxychloride. Most basic salts are insoluble or slightly soluble.

The latter dissociate like this:

AlOHCl 2 = AlOH 2 + + 2Cl -

Properties of salts

The first two exchange reactions were discussed in detail earlier.

The third reaction is also an exchange reaction. It flows between salt solutions and is accompanied by the formation of a precipitate, for example:

The fourth salt reaction is related to the position of the metal in the electrochemical voltage series of metals (see “Electrochemical voltage series of metals”). Each metal displaces from salt solutions all other metals located to the right of it in the stress series. This is subject to the following conditions:

1) both salts (both the reacting one and the one formed as a result of the reaction) must be soluble;

2) metals should not interact with water, therefore the metals of the main subgroups of groups I and II (for the latter, starting with Ca) do not displace other metals from salt solutions.

Methods for obtaining salts

Methods of obtaining and Chemical properties salts Salts can be obtained from inorganic compounds of almost any class. Along with these methods, salts of oxygen-free acids can be obtained by direct interaction of a metal and a non-metal (Cl, S, etc.).

Many salts are stable when heated. However, ammonium salts, as well as some salts of low-active metals, weak acids and acids in which elements exhibit higher or lower oxidation states, decompose when heated.

CaCO 3 = CaO + CO 2

2Ag 2 CO 3 = 4Ag + 2CO 2 + O 2

NH 4 Cl = NH 3 + HCl

2KNO 3 = 2KNO 2 + O 2

2FeSO 4 = Fe 2 O 3 + SO 2 + SO 3

4FeSO 4 = 2Fe 2 O 3 + 4SO 2 + O 2

2Cu(NO 3) 2 = 2CuO + 4NO 2 + O 2

2AgNO3 = 2Ag + 2NO2 + O2

NH 4 NO 3 = N 2 O + 2H 2 O

(NH 4) 2 Cr 2 O 7 = Cr 2 O 3 + N 2 + 4H 2 O

2KClO 3 =MnO 2 = 2KCl + 3O 2

4KClO 3 = 3КlO 4 + KCl

When you hear the word “salt”, the first association is, of course, culinary, without which any dish will seem tasteless. But this is not the only substance that belongs to the class chemical substances salt. You can find examples, composition and chemical properties of salts in this article, and also learn how to correctly form the name of any of them. Before we continue, let's agree that in this article we will only consider inorganic medium salts (obtained by reacting inorganic acids with complete replacement of hydrogen).

Definition and chemical composition

One definition of salt is:

(i.e., consisting of two parts), which includes metal ions and an acid residue. That is, it is a substance obtained as a result of the reaction of an acid and hydroxide (oxide) of any metal.

There is another definition:

This is a compound that is the product of the complete or partial replacement of hydrogen ions of an acid with metal ions (suitable for medium, basic and acidic).

Both definitions are correct, but do not reflect the whole essence of the process of obtaining salt.

Classification of salts

Considering various representatives class of salts, you can see that they are:

Oxygen-containing (salts of sulfuric, nitric, silicic and other acids, the acid residue of which includes oxygen and another non-metal).
Oxygen-free, i.e. salts formed during a reaction whose residue does not contain oxygen - hydrochloric, hydrobromic, hydrogen sulphide and others.

By the number of substituted hydrogens:

Monobasic: hydrochloric, nitrogen, hydrogen iodide and others. The acid contains one hydrogen ion.
Dibasic: Two hydrogen ions are replaced by metal ions to form a salt. Examples: sulfuric, sulphurous, hydrogen sulphide and others.
Tribasic: in the acid composition, three hydrogen ions are replaced by metal ions: phosphoric.

There are other types of classifications based on composition and properties, but we will not discuss them, since the purpose of the article is slightly different.

Learning to name correctly

Any substance has a name that is understandable only to residents of a certain region; it is also called trivial. Table salt is an example of a colloquial name; according to international nomenclature, it will be called differently. But in a conversation, absolutely any person familiar with the nomenclature of names will easily understand that we're talking about about substance with chemical formula NaCl. This salt is a derivative of hydrochloric acid, and its salts are called chlorides, that is, it is called sodium chloride. You just need to learn the names of the salts given in the table below, and then add the name of the metal that formed the salt.

But the name is so easy to formulate if the metal has a constant valence. Now let’s look at the name), which has a metal with variable valence - FeCl 3. The substance is called ferric chloride. This is exactly the right name!

Acid formula	Acid name	Acid residue (formula)	Nomenclature name	Example and trivial name
HCl	salt	Cl-	chloride	NaCl (table salt, rock salt)
HI	hydrogen iodide	I -	iodide	NaI
HF	hydrogen fluoride	F-	fluoride	NaF
HBr	hydrobromic	Br-	bromide	NaBr
H2SO3	sulfurous	SO 3 2-	sulfite	Na2SO3
H2SO4	sulfuric	SO 4 2-	sulfate	CaSO 4 (anhydrite)
HClO	hypochlorous	ClO-	hypochlorite	NaClO
HClO2	chloride	ClO2 -	chlorite	NaClO2
HClO3	hypochlorous	ClO3 -	chlorate	NaClO3
HClO4	chlorine	ClO4 -	perchlorate	NaClO4
H2CO3	coal	CO 3 2-	carbonate	CaCO 3 (limestone, chalk, marble)
HNO3	nitrogen	NO 3 -	nitrate	AgNO 3 (lapis)
HNO2	nitrogenous	NO 2 -	nitrite	KNO 2
H3PO4	phosphorus	PO 4 3-	phosphate	AlPO 4
H2SiO3	silicon	SiO 3 2-	silicate	Na 2 SiO 3 (liquid glass)
HMnO4	manganese	MnO4-	permanganate	KMnO 4 (potassium permanganate)
H2CrO4	chrome	CrO 4 2-	chromate	CaCrO4
H2S	hydrogen sulfide	S-	sulfide	HgS (cinnabar)

Chemical properties

As a class, salts are characterized by their chemical properties by the fact that they can interact with alkalis, acids, salts and more active metals:

1. When interacting with alkalis in solution, a prerequisite for the reaction is the precipitation of one of the resulting substances.

2. When interacting with acids, the reaction takes place if a volatile acid, insoluble acid or insoluble salt is formed. Examples:

Carbonic acid is a volatile acid, as it easily disintegrates into water and carbon dioxide: MgCO 3 + 2HCl = MgCl 2 + H 2 O + CO 2.
Insoluble acid - silicic acid, is formed as a result of the reaction of silicate with another acid.
One of the signs chemical reaction is precipitation. Which salts can be seen in the solubility table.

3. The interaction of salts with each other occurs only in the case of binding of ions, i.e. one of the formed salts precipitates.

4. To determine whether a reaction will occur between a metal and a salt, you need to refer to the metal voltage table (sometimes called the activity series).

Only more active metals (located to the left) can displace metal from the salt. An example is the reaction of an iron nail with copper sulfate:

CuSO 4 + Fe= Cu + FeSO 4

Such reactions are characteristic of most representatives of the salt class. But there are also more specific reactions in chemistry, the properties of the salt reflect individual properties, for example, decomposition during incandescence or the formation of crystalline hydrates. Each salt is individual and unusual in its own way.

In the previous sections, reactions in which salts are formed were constantly encountered.

Salts are substances in which metal atoms are bonded to acidic residues.

The exception is ammonium salts, in which it is not metal atoms, but NH 4 + particles that are associated with acidic residues. Examples of typical salts are given below.

NaCl – sodium chloride,

Na 2 SO 4 – sodium sulfate,

CaSO 4 – calcium sulfate,

CaCl 2 – calcium chloride,

(NH 4) 2 SO 4 – ammonium sulfate.

The formula of the salt is built taking into account the valencies of the metal and the acid residue. Almost all salts are ionic compounds, so we can say that in salts metal ions and ions of acidic residues are interconnected:

Na + Cl – – sodium chloride

Ca 2+ SO 4 2– – calcium sulfate, etc.

The names of salts are made up of the name of the acid residue and the name of the metal. The main thing in the name is the acid residue. The names of salts depending on the acid residue are shown in Table 4.6. The upper part of the table shows oxygen-containing acidic residues, and the lower part shows oxygen-free residues.

Table 4-6. Construction of names of salts.

Salt of which acid	Acid residue	Valency of the residue	Name of salts
Nitrogen HNO 3				Ca(NO 3)2 calcium nitrate
Silicon H 2 SiO 3			silicates	Na 2 SiO 3 sodium silicate
Sulfuric H2SO4			sulfates	PbSO 4 lead sulfate
Coal H2CO3			carbonates	Na 2 CO 3 sodium carbonate
Phosphorus H 3 PO 4				AlPO 4 aluminum phosphate

Hydrogen bromide HBr		NaBr sodium bromide
Hydrogen iodide HI		KI potassium iodide
Hydrogen sulfide H 2 S	sulfides	FeS iron(II) sulfide
Salt HCl		NH 4 Cl ammonium chloride
Hydrofluoride HF		CaF 2 calcium fluoride

From Table 4-6 it can be seen that the names of oxygen-containing salts have the endings “ at", and the names of oxygen-free salts have the endings " eid».

In some cases, the ending "" may be used for oxygenated salts. it"For example, Na 2 SO 3 - sulfite sodium This is done in order to distinguish between salts of sulfuric acid (H 2 SO 4) and sulfurous acid (H 2 SO 3) and in other similar cases.

All salts are divided into medium, sour And basic. Average salts contain only metal atoms and an acid residue. For example, all salts from Table 4-6 are average salts.

Any salt can be obtained by an appropriate neutralization reaction. For example, sodium sulfite is formed in the reaction between sulfurous acid and base (caustic soda). In this case, for 1 mole of acid it is required to take 2 moles of base:

If you take only 1 mole of base - that is, less than is required for full neutralization, then it is formed sour salt – sodium hydrosulfite:

Sour salts are formed by polybasic acids. Monobasic acids do not form acid salts.

Acidic salts, in addition to metal ions and an acid residue, contain hydrogen ions.

The names of acid salts contain the prefix “hydro” (from the word hydrogenium - hydrogen). For example:

NaHCO 3 – sodium bicarbonate,

K 2 HPO 4 – potassium hydrogen phosphate,

KH 2 PO 4 – potassium dihydrogen phosphate.

Basic salts are formed when the base is incompletely neutralized. The names of the main salts are formed using the prefix “hydroxo”. Below is an example showing the difference between basic salts and ordinary (medium) salts:

Basic salts, in addition to metal ions and an acid residue, contain hydroxyl groups.

Basic salts are formed only from polyacid bases. Monoacid bases cannot form such salts.

Table 4.6 shows international titles salts However, it is also useful to know the Russian names and some historical, traditional names of salts that are important (Table 4.7).

Table 4.7. International, Russian and traditional names of some important salts.

International name	Russian name	Traditional name	Application
Sodium carbonate	Sodium carbonate		In everyday life - as a detergent and cleaning agent
Sodium bicarbonate	Sodium carbonate acid	Baking soda	Food product: baked confectionery
Potassium carbonate	Potassium carbonate		Used in technology
Sodium sulfate	Sodium sulfate	Glauber's salt	Medicine
Magnesium sulfate	Magnesium sulfate	Epsom salt	Medicine
Potassium chlorate	Potassium perchloric acid	Bertholet's salt	Used in incendiary mixtures for match heads

For example, in no case should you confuse soda Na 2 CO 3 and baking soda NaHCO3. If accidentally used as food soda instead of baking soda, you can get a severe chemical burn.

In chemistry and technology, many ancient names are still preserved. For example, caustic soda- not a salt at all, but the technical name for sodium hydroxide NaOH. If ordinary soda can be used to clean the sink or dishes, then under no circumstances should caustic soda be handled or used in everyday life!

The structure of salts is similar to the structure of the corresponding acids and bases. Below are the structural formulas of typical intermediate, acidic and basic salts.

Let us give the structure and name of the main salt, the formula of which is: 2 CO 3 – iron (III) dihydroxycarbonate. When considering the structural formula of such a salt, it becomes clear that this salt is the product of partial neutralization of iron (III) hydroxide with carbonic acid: