Ammonium salts decompose when heated if. Chemistry for dummies: Ammonium salts. Application of ammonia and ammonium salts

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Lesson type: lesson using multimedia

Lesson objectives:

• Educational: Systematize students’ knowledge about salts; formation at the interdisciplinary level of a system of knowledge about ammonium salts, which are of great practical importance.
• Educational: develop practical skills in conducting qualitative reactions to ammonium salts; the ability to analyze what you see; development of logical thinking; development of cognitive interest when performing theoretical and practical tasks.
• Educational: Increase cognitive activity and activity of students; developing the ability to work in a team.

Lesson equipment and reagents:

1. On the teacher’s desk: solution of hydrochloric acid HCl; ammonium hydroxide NH 4 OH; ammonium chloride NH 4 Cl; sodium chloride NaCl; water H 2 O; litmus; phenolphthalein; Ammonium bichromate (NH 4) 2 Cr 2 O 7.

2. On the students’ table: ammonium sulfate (NH 4) 2 SO 4; sulfuric acid H 2 SO 4; barium chloride BaCl; ammonium chloride NH 4 Cl; sodium hydroxide NaOH;

3.Interactive board.

Main questions:

• Determination of ammonium salts.
• The role of ammonium salts in the national economy.
• Physical and chemical properties of ammonium salts.
• Preparation of ammonium salts.
• Qualitative reactions to ammonium salts.

Basic concepts: Ammonium cation, ammonium salts.

During the classes

1. Organizational moment

The teacher checks readiness for the lesson and announces the topic of the lesson.

2. Testing basic knowledge (10 min)

There are substances (salts) in glass containers on the teacher’s desk.

Teacher: This container contains an amazing substance. It was once considered “the grace of God,” a symbol of well-being.

:. But it can also destroy living things; because of it, even the sea can become dead.

However, it is difficult to list where it is used.

What is in this bottle?

(Suggested answer is salt.)

What substances do we classify as salts?

Training exercise:

Select salts from the listed substances and name them:

KCl	NaOH	KOH	CO2
H2SO4	Ba(NO3)2	CuSO4	MgO
NH4Cl	H2S	AgNO3	(NH 4) 2 SO 4

Teacher: What unusual salts have you come across?

These salts contain a complex cation - ammonium cation.

The teacher asks the class to formulate the concept of ammonium salt (salts consisting of ammonium cations and anions of an acid residue).

Teacher: Where do you think these salts can be used? Why?

Students: In agriculture, because they contain a vital element for plants - nitrogen.

For a comprehensive description of the practical significance of ammonium salts, it is advisable to listen to a mini report from students.

3. Learning new material (15 min)

Teacher: Let's study the physical and chemical properties of ammonium salts in practice.

What do the physical properties of salts and ammonium salts have in common?

Students: solid, white, crystalline substances, highly soluble in water, electrolytes.

Teacher: Check the solubility of ammonium sulfate in practice, write down the physical properties in your notebook ( conducting an experiment).

Teacher: Let's consider the chemical properties of ammonium salts.

Let us recall the general properties of salts:

(A supporting summary is compiled in the notebook) .

A) dissociation - let’s write the equations for the dissociation of salts

• Ammonium chloride
• Ammonium sulfate

B) Interaction with acids

2 NH 4 Cl + H 2 SO 4 (NH 4) 2 SO 4 + 2 HCl

Carry out the experiment, indicate the signs of the reaction ( conducting an experiment).

B) Interaction with alkalis.

Place phenolphthalein paper into a test tube and observe a color change ( conducting an experiment)

Conclusion: this reaction is qualitative for ammonium salts

D) Interaction with salts

NH 4 Cl + AgNO 3 NH 4 NO 3 + AgCl

Students perform an experiment, write down the reaction equation and check them independently with the equation on the slide ( conducting an experiment).

Creative task: Determine which of the three test tubes contains ammonium sulfate. Write down the equations of the reactions performed ( conducting an experiment).

Specific properties of salts:

D) Decomposition of ammonium salts

Demonstration experiment: decomposition of ammonium dichromate; ammonium chloride:

NH 4 Cl NH 3 + HCl

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

E) Hydrolysis of ammonium salts

NH 4 Cl + H 2 O NH 4 OH + HCl

Demonstration experience.

Conclusion: the medium is alkaline, litmus is blue, phenolphthalein is crimson.

Teacher: Remember in what ways salts can be obtained.

Students: When a base and an acid interact; salts and salts; salts and acids.

The teacher demonstrates experiments, students write down a supporting summary using a slide.

A) NH 4 OH + HCl NH 4 Cl + H 2 O

B) (NH 4) 2 SO 4 + BaCl 2 BaSO 4 + 2 NH 4 Cl

B) (NH 4) 2 CO 3 + 2HCl 2 NH 4 Cl + H 2 O + CO 2

Conclusion: when writing equations, it is necessary to comply with the condition of irreversibility of chemical reactions.

4. Consolidation of the material covered (15 min)

Exercise No. 1.

Select and name ammonium salts:

Option I	Option II
NaNO3	BaCl2

Peer testing in pairs.

Self-test.

NH 3 + HCl NH 4 Cl

2NH 3 + H 2 SO 4 (NH 4) 2 SO 4c) 3

React with sulfuric acid

The correct answer on the slide is marked with dots in the picture, then the dots are connected to form a smile.

Students compare their answers with the example on the screen and try to independently analyze the mistakes they made. The teacher corrects the students' answers.

Exercise No. 4.(A game exercise that develops the children’s desire to find the correct answer, after which they can open the safe).

"Golden Key"

Determine the safe code.

List the sequence of numbers (in ascending order) that determine the properties of ammonium sulfate.

Test:

1. Dissolves in water.
2. Not electrolytes.
3. White crystalline substance.
4. Smells like ammonia.
5. Reacts with barium chloride.
6. Reacts with calcium hydroxide.
7. Decomposes when heated.
8. I DON'T KNOW THE WORDS
9. reacts with orthophosphoric acid.
10. Reacts with I DON'T KNOW THE NAME

Answer: 1345678

The teacher asks the children to write down possible reaction equations.

5. Homework

Creative task: White salt, soluble in water, with silver nitrate forms a white cheesy precipitate, the combustion of which produces nitrogen. Name the salt, write the reaction equations in molecular and ionic form.

6. Lesson conclusions (3 min)

Completing the lesson in an interesting, creative form will put every child in a good mood and increase the quality of learning the material learned in the lesson.

Composing a cinquain (an interesting, non-rhyming poem that requires information in clear terms, which allows you to describe what you saw and heard):

Students write a syncwine, working in pairs, using the textbook and supporting notes.

• Ammonium salts
• Useful, important
• Transform deserts into oases
• React like all salts with salts, acids and alkalis
• They decompose and are used in agriculture.

7. Summing up the lesson, the teacher quotes the words:“The thinking mind does not feel happy until it manages to connect disparate facts into one” (Hevelsey).

>> Chemistry: Ammonium salts

As was said, the ammonium cation NH4+ plays the role of a metal cation and it forms salts with acidic residues: NH4NO3 - ammonium nitrate, or ammonium nitrate, (NH4)2SO4 - ammonium sulfate, etc.

All ammonium salts are crystalline solids, highly soluble in water. In a number of properties they are similar to alkali metal salts, and primarily to potassium salts, since the radii of the K+ and NH+ ions are approximately equal.

Ammonium salts are obtained by reacting ammonia or its aqueous solution with acids.

They have all the properties of salts due to the presence of acidic residues. For example, ammonium chloride or sulfate reacts with silver nitrate or barium chloride, respectively, forming characteristic precipitates. Ammonium carbonate reacts with acids because the reaction produces carbon dioxide.

In addition, the ammonium ion provides another property common to all ammonium salts: its salts react with alkalis when heated to release ammonia.

This reaction is a qualitative reaction to ammonium salts, since the ammonia formed is easily detected (how exactly?).

The third group of properties of ammonium salts is their ability to decompose when heated, releasing ammonia gas, for example:

NH4Сl = NH3 + HCl

This reaction also produces gaseous hydrogen chloride, which evaporates along with ammonia, and upon cooling combines with it again, forming a salt, i.e., when heated in a test tube, dry ammonium chloride sublimes, but white crystals appear on the upper cold walls of the test tube again NН4Сl (Fig. 32).

The main areas of application of ammonium salts were shown earlier, in Figure 31. Here we draw your attention to the fact that almost all ammonium salts are used as nitrogen fertilizers. As you know, plants are able to absorb nitrogen only in bound form, that is, in the form of NH4 or N03 ions. The remarkable Russian agrochemist D.N. Pryanishnikov found that if a plant has a choice, it prefers the ammonium cation to the nitrate anion, so the use of ammonium salts as nitrogen fertilizers is especially effective. A very valuable nitrogen fertilizer is ammonium nitrate NH4NO3.

Let us note other areas of application of some ammonium salts.

Ammonium chloride NH4Cl is used for soldering, as it cleans the metal surface of the oxide film and solder adheres well to it.

Ammonium bicarbonate NH4NC03 and ammonium carbonate (NH4)2CO3 are used in confectionery, as they easily decompose when heated and form gases that loosen the dough and make it fluffy, for example:

NH4HC03 = NH3 + H20 + CO2

Ammonium nitrate NН4NO3 mixed with aluminum and coal powders is used as an explosive - ammonal, which is widely used in mining.

1. Ammonium salts.

2. Properties of ammonium salts due to ammonium ion, acidic residues. Decomposition of ammonium salts.

3. Qualitative reaction to ammonium ion.

4. Ammonium chloride, nitrate, carbonate and their applications.

Write the reaction equations (in molecular and ionic forms) between the following pairs of substances: a) ammonium sulfate and barium chloride; b) ammonium chloride and silver nitrate.

Write reaction equations characterizing the properties of ammonium carbonate: interaction with acid, alkali, salt and decomposition reaction. Write the first three equations also in ionic form.

With polybasic acids, ammonia forms not only intermediate, but also acidic salts. Write the formulas of the acid salts that it can give when reacting with phosphoric acid. Name them and write the dissociation equations for these salts.

Draw up molecular and, where possible, ionic reaction equations that can be used to carry out the following transitions:

N2 -> NH3 -> (NH4)2 HPO4 -> NH4Cl -> NH4NO3

Determine the amount of substance, volume and mass of ammonia required to produce 250 kg of ammonium sulfate used as fertilizer.

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Nitrogen forms several compounds with hydrogen; Of these, the most important is ammonia - a colorless gas with a characteristic pungent odor (the smell of “ammonia”).

In the laboratory, ammonia is usually produced by heating ammonium chloride with slaked lime. The reaction is expressed by the equation

The released ammonia contains water vapor. To dry it, it is passed through soda lime (a mixture of lime and caustic soda).

Rice. 114. A device for demonstrating the combustion of ammonia in oxygen.

The mass of 1 liter of ammonia under normal conditions is 0.77 g. Since this gas is much lighter than air, it can be collected in vessels turned upside down.

When cooled to ammonia under normal pressure it turns into a clear liquid that solidifies at .

The electronic structure and spatial structure of the ammonia molecule are discussed in § 43. In liquid ammonia, the molecules are connected to each other by hydrogen bonds, which determines the relatively high boiling point of ammonia, which does not correspond to its low molecular weight (17).

Ammonia is very soluble in water: 1 volume of water dissolves about 700 volumes of ammonia at room temperature. The concentrated solution contains (mass) and has a density of . A solution of ammonia in water is sometimes called ammonia. Regular medical ammonia contains. As the temperature increases, the solubility of ammonia decreases, so it is released from a concentrated solution when heated, which is sometimes used in laboratories to obtain small quantities of ammonia gas.

At low temperatures, a crystalline hydrate can be isolated from an ammonia solution, melting at -. A crystalline hydrate of the composition is also known. In these hydrates, water and ammonia molecules are connected to each other by hydrogen bonds.

Chemically, ammonia is quite active; it interacts with many substances. In ammonia, nitrogen has the lowest oxidation state. Therefore, ammonia has only reducing properties. If a current is passed through a tube inserted into another wide tube (Fig. 114), through which oxygen passes, the ammonia can be easily ignited; it burns with a pale greenish flame. When ammonia burns, water and free nitrogen are formed:

Under other conditions, ammonia can be oxidized to nitrogen oxide (see § 143).

Unlike hydrogen compounds of non-metals of groups VI and VII, ammonia does not have acidic properties. However, hydrogen atoms in its molecule can be replaced by metal atoms.

When hydrogen is completely replaced by a metal, compounds called nitrides are formed. Some of them, such as calcium and magnesium nitrides, are obtained by the direct reaction of nitrogen with metals at high temperatures;

When in contact with water, many nitrides completely hydrolyze to form ammonia and metal hydroxide. For example:

When only one hydrogen atom in ammonia molecules is replaced by metals, metal amides are formed. Thus, by passing ammonia over molten sodium, sodium amide can be obtained in the form of colorless crystals:

Water decomposes sodium amide;

Possessing strong basic and water-removing properties, sodium amide has found use in some organic syntheses, for example, in the production of indigo dye and some drugs.

Hydrogen in ammonia can also be replaced by halogens. Thus, the action of chlorine on a concentrated solution of ammonium chloride produces chlorine nitride, or nitrogen chloride,

in the form of a heavy oily explosive liquid.

Iodine nitride (nitrogen iodide), which is formed in the form of a black, water-insoluble powder when iodine reacts with ammonia, has similar properties. When wet it is safe, but when dried it explodes at the slightest touch; in this case, violet iodine vapor is released.

With fluorine, nitrogen forms stable nitrogen fluoride.

From the data in table. 6 (p. 118) it can be seen that the electronegativity of chlorine and sodium is less, and fluorine is greater, than the electronegativity of nitrogen. It follows that in compounds and the oxidation degree of nitrogen is -3, and in it is equal to . Therefore, nitrogen fluoride differs in properties from chlorine and iodine nitrides. For example, when interacting with water, ammonia is formed, and in this case, nitrogen oxide (III) is obtained;

The nitrogen atom in the ammonia molecule is connected by three covalent bonds to hydrogen atoms and retains one lone pair of electrons:

Acting as a donor of an electron pair, the nitrogen atom can participate in the formation of a fourth covalent bond with other atoms or ions that have electron-withdrawing properties using the donor-acceptor method.

This explains the extremely characteristic ability of ammonia to enter into addition reactions.

Examples of complex compounds formed by ammonia as a result of addition reactions are given in and 201, as well as in Chap. XVIII. Above (p. 124) the interaction of a molecule with a hydrogen ion, leading to the formation of ammonium ion, has already been considered:

In this reaction, ammonia serves as a proton acceptor and, therefore, from the point of view of the proton theory of acids and bases (p. 237), exhibits the properties of a base. Indeed, when reacting with acids that are in a free state or in solution, ammonia neutralizes them, forming ammonium salts. For example, with hydrochloric acid we get ammonium chloride:

The interaction of ammonia with water also leads to the formation of not only ammonia hydrates, but also partially ammonium ions:

As a result, the concentration of ions in the solution increases. This is why aqueous solutions of ammonia have an alkaline reaction. However, according to established tradition, an aqueous solution of ammonia is usually designated by the formula and called ammonium hydroxide, and the alkaline reaction of this solution is considered as the result of the dissociation of molecules.

Ammonia is a weak base. When the equilibrium constant of its ionization (see the previous equation) is equal to . A one-molar aqueous solution of ammonia contains only 0.0042 equivalents of and ions; such a solution has .

Most ammonium salts are colorless and highly soluble in water. In some of their properties they are similar to salts of alkali metals, especially potassium (the ions have similar sizes).

Since an aqueous solution of ammonia is a weak base, ammonium salts in solutions hydrolyze. Solutions of salts formed by ammonia and strong acids have a slightly acidic reaction.

Ammonium ion hydrolysis is usually written in this form:

However, it is more correct to consider it as a reversible transition of a proton from an ammonium ion to a water molecule:

When an alkali is added to an aqueous solution of any ammonium salt, the ions are bound by OH- ions into water molecules and the hydrolysis equilibrium shifts to the right. The process that occurs can be expressed by the equation:

When the solution is heated, ammonia evaporates, which is easy to see by the smell. Thus, the presence of any ammonium salt in a solution can be detected by heating the solution with an alkali (reaction to ammonium).

Ammonium salts are thermally unstable. When heated they decompose. This decomposition may occur reversibly or irreversibly. Ammonium salts, the anion of which is not an oxidizing agent or only weakly exhibits oxidizing properties, decompose reversibly. For example, when heated, ammonium chloride sublimes - it decomposes into ammonia and hydrogen chloride, which on the cold parts of the vessel recombine into ammonium chloride:

During the reversible decomposition of ammonium salts formed by non-volatile acids, only ammonia evaporates. However, the decomposition products - ammonia and acid - when mixed, recombine with each other. Examples include the decomposition reactions of ammonium sulfate or ammonium phosphate.

Ammonium salts, the anion of which exhibits more pronounced oxidizing properties, decompose irreversibly: a redox reaction occurs, during which ammonium is oxidized and the anion is reduced. Examples include the decomposition (§ 136) or decomposition of ammonium nitrate:

Ammonia and ammonium salts are widely used. As already mentioned, ammonia, even at low pressure, easily turns into liquid. Since a large amount of heat (1.37) is absorbed during the evaporation of liquid ammonia, liquid ammonia is used in various refrigeration devices.

Aqueous solutions of ammonia are used in chemical laboratories and industries as a weak, highly volatile base; They are also used in medicine and in everyday life. But most of the ammonia produced in industry is used for the preparation of nitric acid, as well as other nitrogen-containing substances. The most important of these include nitrogen fertilizers, primarily ammonium sulfate and nitrate and urea (p. 427).

Ammonium sulfate serves as a good fertilizer and is produced in large quantities.

Ammonium nitrate is also used as a fertilizer; The percentage of assimilable nitrogen in this salt is higher than in other nitrates or ammonium salts. In addition, ammonium nitrate forms explosive mixtures with flammable substances (ammonals) used for blasting.

Ammonium chloride, or ammonia, is used in dyeing, calico printing, soldering and tinning, as well as in galvanic cells. The use of ammonium chloride in soldering is based on the fact that it helps remove oxide films from the metal surface, so that the solder adheres well to the metal. When a highly heated metal comes into contact with ammonium chloride, the oxides located on the surface of the metal are either reduced or turn into chlorides. The latter, being more volatile than oxides, are removed from the metal surface. For the case of copper and iron, the main processes occurring can be expressed by the following equations:

The first of these reactions is redox: copper, being a less active metal than iron, is reduced by ammonia, which is formed when heated.

Liquid ammonia and solutions of ammonium salts saturated with it are used as fertilizers. One of the main advantages of such fertilizers is their increased nitrogen content.

Ammonia

Physical properties: ammonia (NH3)– colorless gas with a pungent odor, soluble in water, 2 times lighter than air; when cooled to -33.4 °C and normal pressure, it turns into a transparent liquid; at 77.8 °C it solidifies. The mass fraction of ammonia in the concentrated solution is 25%. A solution of NH3 in water - ammonia water or ammonia. Medical ammonia – 10%. At low temperatures, crystalline hydrate NH3 forms in solution? H2O. Molecule structure: characterized by sp3 hybridization. The formation of a molecule involves 3 unpaired p-electrons of nitrogen and 1s electrons of hydrogen atoms. The molecule has the shape of a regular pyramid, with nitrogen atoms at the top and hydrogen atoms at the corners.

Chemical properties:

1) when NH3 is dissolved in water, hydrated ammonia molecules and partially ammonium ions are formed - NH4+ and OH-ions - an aqueous solution of ammonia has a slightly alkaline reaction.

2) NH3 interacts with acids: NH3 + H2SO4 = NH4HSO4;

3) ammonia is a strong reducing agent. When heated, it reduces Cu from CuO: 3CuO + 2NH3 = Cu + N2 + 3H2O;

4) in oxygen NH3 burns with a yellow flame: 4NH3 + 3O2 = 2N2? + 6H2O;

5) NH3 is oxidized by atmospheric oxygen in the presence of catalysts: Pt, Cr2O3, Rh: 4NH3 + 5O2 = 4NO? + 6H2O;

6) when replacing hydrogen with metals, amides are formed: Na + NH3 = NaNH2 + 1/2 H2;

7) hydrogen in NH3 can be replaced by halogens. When a solution of ammonium chloride is exposed to gaseous chlorine, nitrogen chloride is formed: NH4Cl + 3Cl2 = 4HCl + NCl3.

Ammonia (nitrogen chloride).

Receipt: in industry until the end of the 19th century century ammonia was obtained as a by-product during the coking of coal, which contains up to 1–2% nitrogen.

At first XX century New industrial methods for the production of ammonia have been developed, based on the binding or fixation of atmospheric nitrogen.

In 1904 a cyamide method has appeared, based on the ability of nitrogen to react with calcium carbide at high temperatures, forming calcium cyamide CaCN2, which, when exposed to water vapor at a pressure of 0.6 MPa, easily decomposes into ammonia and calcium carbonate:

Later, another way to produce ammonia appeared - the direct interaction of nitrogen and oxygen under the influence of electrical discharges, but this reaction was reversible until optimal conditions were found for it. These conditions were high pressure and low temperature, the use of catalysts - sponge iron with additives of activators (oxides of aluminum, potassium, calcium, silicon, magnesium).

Ammonium salts– complex substances including ammonium cations NH4+ and acid residues.

Physical properties: Ammonium salts are crystalline solids that are highly soluble in water.

Chemical properties: Ammonium has the properties of a metal, therefore the structure of its salts is similar to alkali metal salts, since NH4+ ions and alkali metal (potassium) ions have approximately the same radii. Ammonium does not exist in its free form, because it is chemically unstable and instantly decomposes into ammonia and hydrogen. Evidence of the metallic nature of ammonium is the presence of ammonium amalgam - an alloy of ammonium with mercury, similar to that of alkali metals. When treating ammonium amalgam with a cold solution of copper sulfate, the amalgam will displace the nth amount of copper:

Ammonium salts have an ionic lattice and have all the properties of typical salts:

1) are strong electrolytes - they undergo dissociation in aqueous solutions, forming an ammonium cation and an acid anion:

2) undergo hydrolysis (salt of a weak base and a strong acid):

acidic environment, pH<7, лакмус красный;

3) enter into an exchange reaction with acids and salts:

4) interact with alkali solutions to form ammonia - a qualitative reaction to ammonium ion:

ammonium salts are determined by the smell of ammonia released as a result of the reaction, as well as by the blue color of litmus;

5) decompose when heated:

Receipt: NH3 + HNO3 = NH4NO3 (ammonium nitrate); 2NH4OH + H2SO4 = (NH4)2SO4 (ammonium sulfate) + 2H2O.

Application: ammonium salts are widely used in practice: ammonium sulfate - (NH4)2SO4, ammonium nitrate - NH4NO3, ammonium dihydrogen phosphate - NH4H2PO4 and ammonium hydrogen phosphate - (NH4)2HPO4 are used as mineral fertilizer. The advantage of the fertilizer is its increased ammonia content. Ammonium chloride (NH4Cl) is used - ammonia.

Ammonium salts

TO The ammonium ion NH4+ plays the role of a metal cation and it forms salts with acidic residues: NH4NO3 - ammonium nitrate, or ammonium nitrate, (NH4)2SO4 - ammonium sulfate, etc.

All ammonium salts are crystalline solids, highly soluble in water. In a number of properties they are similar to alkali metal salts, and primarily to potassium salts, since the radii of the K+ and NH+ ions are approximately equal.

Ammonium salts are obtained by reacting ammonia or its aqueous solution with acids.

They have all the properties of salts due to the presence of acidic residues. For example, ammonium chloride or sulfate reacts with silver nitrate or barium chloride, respectively, forming characteristic precipitates. Ammonium carbonate reacts with acids because the reaction produces carbon dioxide.

In addition, the ammonium ion provides another property common to all ammonium salts: its salts react with alkalis when heated to release ammonia.

This reaction is a qualitative reaction to ammonium salts, since the ammonia formed is easily detected (how exactly?).

The third group of properties of ammonium salts is their ability to decompose when heated, releasing ammonia gas, for example:

NH4Сl = NH3 + HCl

This reaction also produces gaseous hydrogen chloride, which evaporates along with ammonia, and upon cooling combines with it again, forming a salt, i.e., when heated in a test tube, dry ammonium chloride sublimes, but white crystals appear on the upper cold walls of the test tube again NН4Сl (Fig. 32).

The main areas of application of ammonium salts were shown earlier, in Figure 31. Here we draw your attention to the fact that almost all ammonium salts are used as nitrogen fertilizers. As you know, plants are able to absorb nitrogen only in bound form, that is, in the form of NH4 or N03 ions. The remarkable Russian agrochemist D.N. Pryanishnikov found that if a plant has a choice, it prefers the ammonium cation to the nitrate anion, so the use of ammonium salts as nitrogen fertilizers is especially effective. A very valuable nitrogen fertilizer is ammonium nitrate NH4NO3.

Let us note other areas of application of some ammonium salts.

Ammonium chloride NH4Cl is used for soldering, as it cleans the metal surface of the oxide film and solder adheres well to it.

Ammonium bicarbonate NH4NC03 and ammonium carbonate (NH4)2CO3 are used in confectionery, as they easily decompose when heated and form gases that loosen the dough and make it fluffy, for example:

NH4HC03 = NH3 + H20 + CO2

Ammonium nitrate NН4NO3 mixed with aluminum and coal powders is used as an explosive - ammonal, which is widely used in mining.