The table of solubility of salts, acids and bases is the foundation, without which a full-fledged development of chemical knowledge is impossible. The solubility of bases and salts helps in teaching not only schoolchildren, but also professional people. The creation of many waste products cannot do without this knowledge.

Solubility table of acids, salts and bases in water

The table of solubility of salts and bases in water is a guide that helps in mastering the chemical basics. The following notes will help you understand the table below.

• P - indicates a soluble substance;
• H - insoluble substance;
• M - the substance is slightly soluble in the aqueous medium;
• RK - a substance is capable of dissolving only when exposed to strong organic acids;
• A dash will say that such a creature does not exist in nature;
• NK - does not dissolve in acids or water;
• ? - the question mark indicates that there is no exact information about the dissolution of the substance to date.

Often the table is used by chemists and schoolchildren, students for laboratory research, during which it is necessary to establish the conditions for the occurrence of certain reactions. According to the table, it turns out to find out how a substance will behave in a hydrochloric or acidic environment, whether a precipitate is possible. The precipitate during research and experiments indicates the irreversibility of the reaction. This is an essential point that can affect the course of all laboratory work.

The solubility table of chemical elements is a table with the water solubility of the most famous inorganic acids, bases and salts.

Definition 1

The solubility table in chemistry shows the solubility at 20 ° C, with an increase in temperature, the solubility increases.

A substance is soluble in water if its solubility is more than 1 g in 100 g of water and insoluble if it is less than 0.1 g / 100 g. For example, having found lithium in the solubility table according to chemistry, you can make sure that almost all of its salts form solutions.

In fig. 1 and fig. 2 shows a photo of a complete table of solubility in chemistry with the names of acid residues.

Figure 1. Photo table of solubility in chemistry 2018-2019

Figure 2. Table for the chemistry of acids and acid residues

To compose the name of the salt, you must use the periodic table and solubility. The name of the metal from the periodic table is added to the name of the acid residue, for example:

$ \ mathrm (Zn_3 (PO_4) _2) $ - zinc phosphate; $ \ mathrm (FeSO_4) $ - iron (II) sulfate.

In brackets with the text name, you must indicate the valency of the metal, if there are several of them. In the case of iron, there is also the salt $ \ mathrm (Fe_2 (SO_4) _3) $ - iron (III) sulfate.

What can you find out using the table of solubility in chemistry

The table of solubility of substances in chemistry with precipitates is used to determine the possibility of any reaction occurring, since the formation of a precipitate or gas is necessary for an irreversible reaction to proceed.

Definition salts within the framework of the theory of dissociation. Salts are usually divided into three groups: medium, sour and basic. In intermediate salts, all hydrogen atoms of the corresponding acid are replaced by metal atoms, in acid salts they are only partially replaced, in basic salts of the OH group of the corresponding base are partially replaced by acid 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 include complex ion, consisting of a central atom bonded to several ligands: K 4 (yellow blood salt), K 3 (red blood salt), Na, Cl; hydrated salts(crystalline hydrates), which contain molecules crystallization water: CuSO 4 5H 2 O (copper sulfate), Na 2 SO 4 10H 2 O (Glauber's salt).

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

For salts of anoxic 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 element name in the case of higher oxidation states — am, in the case of lower oxidation states, the ending -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 manganic 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 KOSl, potassium chlorite KOSl 2, potassium chlorate KOSl 3, potassium perchlorate KOSl 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 the international nomenclature, the hydrogen atom that is part of the acid salt is denoted by the prefix hydro-, OH group - with the 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 indicated first, followed by the name of the metal with the corresponding oxidation state (Roman numerals in brackets). In the names of complex cations, Russian names of metals are used, for example: Cl 2 - tetraammine copper (II) 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).

Hydrate salt names (crystal hydrates) are formed in two ways. The complex cation naming system described above can be used; for example, copper sulfate SO 4 H 2 0 (or CuSO 4 5H 2 O) can be called tetraaquamated (II) sulfate. However, for the most well-known hydrated 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 sulfate (I) pentahydrate, Na 2 SO 4 10H 2 O - sodium sulfate decahydrate, CaCl 2 2H 2 O - calcium chloride dihydrate.

Solubility of salts

According to 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 the solubility of acids, bases and salts in water. If the table is not at hand, then you can use the rules. They are easy to remember.

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

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

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

4. Sodium and potassium salts are soluble.

5. All phosphates, carbonates, silicates and sulfides do not dissolve, except for Na salts + and K + .

Of all the chemical compounds, salts are the most numerous class of substances. These are solids, they differ from each other in color and solubility in water. At the beginning of the XIX century. 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. Average, 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 acid residue anions:

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 a metal cation Na + and an acidic singly charged 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 medium 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 hydroxyl groups in the base for 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 basic cations CuOH + and a doubly charged anion of the acid residue CO 3 2-. The CuOH + cation has a charge of +1, therefore, 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 for normal salts, but with the addition of the prefix hydroxy, (CuOH) 2 CO 3 - copper (II) hydroxycarbonate or AlOHCl 2 - aluminum hydroxychloride. Most of the basic salts are insoluble or slightly soluble.

The latter dissociate like this:

AlOHCl 2 = AlOH 2 + + 2Cl -

Salt properties

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 reaction of salts is associated with the position of the metal in the electrochemical series of metal voltages (see "Electrochemical series of metal voltages"). Each metal displaces from salt solutions all other metals located to the right of it in the series of stresses. This is true if the following conditions are met:

1) both salts (both reacting and resulting from 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.

Salt production methods

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

Many salts are heat stable. However, ammonium salts, as well as some salts of low-activity metals, weak acids and acids, in which the 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

2AgNO 3 = 2Ag + 2NO 2 + O 2

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 = 3KSlO 4 + KCl