Liquid

Ammonia- NH 3, hydrogen nitride, under normal conditions - a colorless gas with a pungent characteristic odor (the smell of ammonia), almost twice as light as air, poisonous. The solubility of NH 3 in water is extremely high - about 1200 volumes (at 0 ° C) or 700 volumes (at 20 ° C) in a volume of water. In refrigeration, it is called R717, where R is Refrigerant (refrigerant), 7 is the type of refrigerant (inorganic compound), 17 is the molecular weight.

The ammonia molecule has the shape of a trigonal pyramid with a nitrogen atom at the top. Three unpaired p-electrons of the nitrogen atom participate in the formation of polar covalent bonds with 1s-electrons of three hydrogen atoms (N-H bonds), the fourth pair of external electrons is unshared, it can form a donor-acceptor bond with a hydrogen ion, forming an ammonium ion NH 4 + . Due to the fact that the non-bonding two-electron cloud is strictly oriented in space, the ammonia molecule has a high polarity, which leads to its good solubility in water.

In liquid ammonia, the molecules are linked by hydrogen bonds. A comparison of the physical properties of liquid ammonia with water shows that ammonia has lower boiling points (t kip -33.35 ° C) and melting points (t pl -77.70 ° C), as well as a lower density, viscosity (viscosity of liquid ammonia 7 times less than the viscosity of water), conductivity and dielectric constant. This is to some extent explained by the fact that the strength of these bonds in liquid ammonia is significantly lower than that of water, and also by the fact that there is only one pair of unshared electrons in the ammonia molecule, in contrast to two pairs in the water molecule, which does not make it possible to form an extensive network of hydrogen bonds between several molecules. Ammonia easily passes into a colorless liquid with a density of 681.4 kg / m³, which strongly refracts light. Like water, liquid ammonia is highly associated, mainly through the formation of hydrogen bonds. Liquid ammonia practically does not conduct electricity. Liquid ammonia is a good solvent for a very large number of organic as well as many inorganic compounds. Solid ammonia is colorless cubic crystals.

Chemical properties

• Due to the presence of a lone electron pair, ammonia acts as a nucleophile or complexing agent in many reactions. So, it attaches a proton, forming an ammonium ion:

NH 3 + H + → NH 4 +

• An aqueous solution of ammonia ("ammonia") has a slightly alkaline reaction due to the process:

NH 3 + H 2 O → NH 4 + + OH - ; K o \u003d 1.8 × 10 −5

• Interacting with acids gives the corresponding ammonium salts:

NH 3 + HNO 3 → NH 4 NO 3

• Ammonia is also a very weak acid (10,000,000,000 times weaker than water), capable of forming salts with metals - amides. Compounds containing NH 2 − ions are called amides, NH 2− - imides, and N 3− - nitrides. Alkali metal amides are obtained by acting on them with ammonia:

2NH 3 + 2K = 2KNH 2 + H 2

Amides, imides and nitrides of a number of metals are formed as a result of certain reactions in liquid ammonia. Nitrides can be obtained by heating metals in a nitrogen atmosphere.

Metal amides are analogues of hydroxides. This analogy is reinforced by the fact that the OH - and NH 2 - ions, as well as the H 2 O and NH 3 molecules, are isoelectronic. Amides are stronger bases than hydroxides, and therefore undergo irreversible hydrolysis in aqueous solutions:

NaNH 2 + H 2 O → NaOH + NH 3 CaNH + 2H 2 O → Ca(OH) 2 + NH 3 Zn 3 N 2 + 6H 2 O → 3Zn(OH) 2 + 2NH 3

and in alcohols:

KNH 2 + C 2 H 5 OH → C 2 H 5 OK + NH 3

Like aqueous solutions of alkalis, ammonia solutions of amides conduct electric current well, which is due to dissociation:

MNH 2 → M + + NH 2 -

Phenolphthalein in these solutions turns red; when acids are added, they are neutralized. The solubility of amides changes in the same sequence as the solubility of hydroxides: LiNH 2 is insoluble, NaNH 2 is slightly soluble, KNH 2 , RbNH 2 and CsNH 2 are highly soluble.

• When heated, ammonia exhibits reducing properties. So, it burns in an oxygen atmosphere, forming water and nitrogen. Oxidation of ammonia with air on a platinum catalyst gives nitrogen oxides, which is used in industry to produce nitric acid:

4NH 3 + 3O 2 → 2N 2 + 6H 2 0 4NH 3 + 5O 2 → 4NO + 6H 2 O

The use of ammonia NH 4 Cl for cleaning the metal surface from oxides during their soldering is based on the reducing ability of NH 3:

3CuO + 2NH 4 Cl → 3Cu + 3H 2 O + 2HCl + N 2

Oxidizing ammonia with sodium hypochlorite in the presence of gelatin, hydrazine is obtained:

2NH 3 + NaClO → N 2 H 4 + NaCl + H 2 O

• Halogens (chlorine, iodine) form dangerous explosives with ammonia - nitrogen halides (nitrogen chloride, nitrogen iodide).

• With haloalkanes, ammonia enters into a nucleophilic addition reaction, forming a substituted ammonium ion (a method for obtaining amines):

NH 3 + CH 3 Cl → CH 3 NH 3 Cl (methyl ammonium hydrochloride)

• With carboxylic acids, their anhydrides, halides, esters and other derivatives gives amides. With aldehydes and ketones - Schiff bases, which can be reduced to the corresponding amines (reductive amination).

• At 1000 °C, ammonia reacts with coal, forming HCN and partially decomposing into nitrogen and hydrogen. It can also react with methane, forming the same hydrocyanic acid:

CH 4 + NH 3 + 1.5O 2 → HCN + 3H 2 O

Name history

Ammonia (in European languages ​​its name sounds like "ammoniac") owes its name to the oasis of Ammon in North Africa, located at the crossroads of caravan routes. In hot climates, urea (NH 2) 2 CO contained in animal waste decomposes especially quickly. One of the degradation products is ammonia. According to other sources, ammonia got its name from the ancient Egyptian word amonian. So called people worshiping the god Amon. During their ritual rites, they sniffed ammonia NH 4 Cl, which, when heated, evaporates ammonia.

Liquid ammonia

Liquid ammonia, although to a small extent, dissociates into ions, in which its similarity with water is manifested:

2NH 3 → NH 4 + + NH 2 -

The self-ionization constant of liquid ammonia at −50 °C is approximately 10 −33 (mol/l)².

Liquid ammonia, like water, is a strong ionizing solvent in which a number of active metals dissolve: alkali, alkaline earth, Mg, Al, as well as Eu and Yb. The solubility of alkali metals in liquid NH 3 is several tens of percent. Liquid ammonia NH 3 also dissolves some intermetallic compounds containing alkali metals, such as Na 4 Pb 9 .

Dilute solutions of metals in liquid ammonia are blue, concentrated solutions have a metallic sheen and look like bronze. During the evaporation of ammonia, alkali metals are isolated in pure form, and alkaline earth metals - in the form of complexes with ammonia [E (NH 3) 6] with metallic conductivity. On slight heating, these complexes decompose into metal and NH 3 .

The metal dissolved in NH 3 gradually reacts to form an amide:

2Na + 2NH 3 → 2NaNH 2 + H 2 -

The metal amides resulting from the reaction with ammonia contain the negative ion NH 2 − , which is also formed during the self-ionization of ammonia. Thus, metal amides are analogues of hydroxides. The reaction rate increases when going from Li to Cs. The reaction is greatly accelerated in the presence of even small impurities of H 2 O.

Metal-ammonia solutions have metallic electrical conductivity; in them, metal atoms decay into positive ions and solvated electrons surrounded by NH 3 molecules. Metal-ammonia solutions containing free electrons are the strongest reducing agents.

complex formation

Due to their electron-donating properties, NH 3 molecules can enter complex compounds as a ligand. Thus, the introduction of excess ammonia into solutions of salts of d-metals leads to the formation of their amino complexes:

CuSO 4 + 4NH 3 → SO 4 Ni(NO 3) 2 + 6NH 3 → (NO 3) 2

Complexation is usually accompanied by a change in the color of the solution, so in the first reaction the blue color (CuSO 4) turns into dark blue (color of the complex), and in the second reaction the color changes from green (Ni (NO 3) 2) to blue-violet. The strongest complexes with NH 3 form chromium and cobalt in the +3 oxidation state.

Biological role

Ammonia is the end product of nitrogen metabolism in humans and animals. It is formed during the metabolism of proteins, amino acids and other nitrogenous compounds. It is highly toxic to the body, so most of the ammonia during the ornithine cycle is converted by the liver into a more harmless and less toxic compound - urea (urea). Urea is then excreted by the kidneys, and some of the urea can be converted by the liver or kidneys back into ammonia.

Ammonia can also be used by the liver for the reverse process, the resynthesis of amino acids from ammonia and amino acid keto analogs. This process is called "reductive amination". Thus, aspartic acid is obtained from oxaloacetic acid, glutamic acid is obtained from α-ketoglutaric acid, etc.

Physiological action

According to the physiological effect on the body, it belongs to the group of substances with an asphyxiant and neurotropic effect, which, when inhaled, can cause toxic pulmonary edema and severe damage to the nervous system. Ammonia has both local and resorptive effects.

Ammonia vapor strongly irritates the mucous membranes of the eyes and respiratory organs, as well as the skin. This is what we perceive as a pungent smell. Ammonia vapors cause profuse lacrimation, pain in the eyes, chemical burns of the conjunctiva and cornea, loss of vision, coughing fits, redness and itching of the skin. When liquefied ammonia and its solutions come into contact with the skin, a burning sensation occurs, a chemical burn with blisters and ulcerations is possible. In addition, liquefied ammonia absorbs heat during evaporation, and frostbite of varying degrees occurs when it comes into contact with the skin. The smell of ammonia is felt at a concentration of 37 mg/m³.

The maximum permissible concentration in the air of the working area of ​​the production facility is 20 mg/m³. Therefore, if the smell of ammonia is felt, then it is already dangerous to work without protective equipment. Irritation of the pharynx is manifested when the ammonia content in the air is 280 mg / m³, the eye - 490 mg / m³. When exposed to very high concentrations, ammonia causes skin lesions: 7-14 g/m³ - erythematous, 21 g/m³ or more - bullous dermatitis. Toxic pulmonary edema develops when exposed to ammonia for an hour with a concentration of 1.5 g / m³. Short-term exposure to ammonia at a concentration of 3.5 g/m³ or more quickly leads to the development of general toxic effects. The maximum permissible concentration of ammonia in the atmospheric air of settlements is: average daily 0.04 mg/m³; maximum single dose 0.2 mg/m³.

In the world, the maximum concentration of ammonia in the atmosphere (more than 1 mg / m³) is observed in the Indo-Gangetic Plain, in the Central Valley of the USA and in the South Kazakhstan region.

Application

Ammonia is one of the most important products of the chemical industry, its annual world production reaches 150 million tons. It is mainly used for the production of nitrogen fertilizers (ammonium nitrate and sulfate, urea), explosives and polymers, nitric acid, soda (ammonia method) and other chemical products. Liquid ammonia is used as a solvent.

In refrigeration, it is used as a refrigerant (R717)

In medicine, a 10% solution of ammonia, often called ammonia, is used for fainting (to stimulate breathing), to stimulate vomiting, as well as externally - neuralgia, myositis, insect bites, treatment of the surgeon's hands. If used incorrectly, it can cause burns of the esophagus and stomach (in case of taking an undiluted solution), reflex respiratory arrest (when inhaled in high concentrations).

Apply topically, inhalation and inside. To excite breathing and remove the patient from fainting, carefully bring a small piece of gauze or cotton wool moistened with ammonia to the patient's nose (for 0.5-1 s). Inside (only in breeding) to induce vomiting. With insect bites - in the form of lotions; with neuralgia and myositis - rubbing with ammonia liniment. In surgical practice, they are bred in warm boiled water and wash their hands.

Since it is a weak base, it neutralizes acids when interacting.

The physiological effect of ammonia is due to the pungent smell of ammonia, which irritates specific receptors of the nasal mucosa and excites the respiratory and vasomotor centers of the brain, causing increased breathing and increased blood pressure.

Receipt

The industrial method for producing ammonia is based on the direct interaction of hydrogen and nitrogen:

N 2 (g) + 3H 2 (g) ↔ 2NH 3 (g) + 45.9 kJ

This is the so-called Haber process (German physicist, developed the physico-chemical foundations of the method).

The reaction occurs with the release of heat and a decrease in volume. Therefore, based on the Le Chatelier principle, the reaction should be carried out at the lowest possible temperatures and at high pressures - then the equilibrium will be shifted to the right. However, the reaction rate at low temperatures is negligible, and at high temperatures, the rate of the reverse reaction increases. Carrying out the reaction at very high pressures requires the creation of special equipment that can withstand high pressure, and hence a large investment. In addition, the equilibrium of the reaction, even at 700 °C, is established too slowly for its practical use.

The use of a catalyst (porous iron with impurities of Al 2 O 3 and K 2 O) made it possible to accelerate the achievement of an equilibrium state. Interestingly, in the search for a catalyst for this role, more than 20 thousand different substances were tried.

Taking into account all the above factors, the process of obtaining ammonia is carried out under the following conditions: temperature 500 ° C, pressure 350 atmospheres, catalyst. The yield of ammonia under such conditions is about 30%. Under industrial conditions, the principle of circulation is used - ammonia is removed by cooling, and unreacted nitrogen and hydrogen are returned to the synthesis column. This turns out to be more economical than achieving a higher reaction yield by increasing the pressure.

To obtain ammonia in the laboratory, the action of strong alkalis on ammonium salts is used:

NH 4 Cl + NaOH = NH 3 + NaCl + H 2 O.

Usually obtained in a laboratory way by weak heating of a mixture of ammonium chloride with slaked lime. 2NH 4 Cl + Ca(OH) 2 = CaCl 2 + 2NH 3 + 2H 2 O

To dry ammonia, it is passed through a mixture of lime and caustic soda.

Very dry ammonia can be obtained by dissolving sodium metal in it and subsequently distilling it. This is best done in a system made of metal under vacuum. The system must withstand high pressure (at room temperature, the saturated vapor pressure of ammonia is about 10 atmospheres). In industry, ammonia is dried in absorption columns.

Ammonia in medicine

For insect bites, ammonia is applied externally in the form of lotions. Side effects are possible: with prolonged exposure (inhalation use), ammonia can cause reflex respiratory arrest. Topical application is contraindicated for dermatitis, eczema, other skin diseases, as well as for open traumatic injuries of the skin. With inhalation application - reflex respiratory arrest, with topical application - irritation, dermatitis, eczema at the site of application. Topical application is possible only on intact skin. In case of accidental damage to the mucous membrane of the eye, rinse with water (for 15 minutes every 10 minutes) or a 5% solution of boric acid. Oils and ointments are not used. With the defeat of the nose and pharynx - 0.5% solution of citric acid or natural juices. In case of ingestion, drink water, fruit juice, milk, preferably 0.5% citric acid solution or 1% acetic acid solution until the contents of the stomach are completely neutralized. Interaction with other drugs is unknown. (Instruction for use)

One of the most important chemicals used in various fields of human activity is ammonia. Every year this substance is produced in huge quantities - more than 100 million tons. Just think about this number! The question immediately arises: “Why produce such an amount of ammonia?”. In this article, we will answer this question, as well as find out the reason for the popularity of ammonia.

Properties of ammonia

The physical and chemical properties of ammonia determine its applications in various fields. Ammonia is a colorless gaseous substance with a very pungent and unpleasant odour. The substance is poisonous. With prolonged exposure to the human body, it can cause swelling and damage to various organs.

Ammonia is a weak acid, it interacts with acids, water, and is able to form salts with metals. It is able to enter into various chemical reactions with other chemicals. For example, the reaction of anhydrous ammonia with nitric acid in practice makes it possible to obtain ammonium nitrate, which is used for the production of fertilizers.

Ammonia is a reducing agent. It is capable of reducing various metals from their oxides. The reaction of ammonia with copper oxide makes it possible to obtain nitrogen.

Various uses of ammonia

Despite its toxicity, ammonia is used in a variety of areas. The main part of the produced ammonia is used for the manufacture of various products of the chemical industry. These products include:

Ammonia and ammonium nitrate fertilizers (ammonium and nitrate nitrate, ammonium sulfate, ammonium chloride, etc.). Such fertilizers are suitable for different crops. It is important to know that the application of fertilizers to the soil is normalized due to the fact that the substances contained in them can migrate to ripe vegetables and fruits.

Soda. There is an ammonia method for obtaining soda ash. Ammonia is used to saturate the brine. This method is actively used for the industrial production of soda.

Nitric acid. Synthetic ammonia is used for its production. At the moment, the industrial production of this substance is based on the phenomenon of catalysis of synthetic ammonia.

Explosives. Ammonium nitrate is neutral to mechanical stress, but under certain conditions it is characterized by high explosive properties. That is why it is used to produce such substances. The result is ammonites - ammonia explosives.

Solvent. Ammonia, in a liquid state, can be used as a solvent for various organic and inorganic substances.

Ammonia - refrigeration unit. Ammonia is used in refrigeration as a refrigerant. Ammonia does not cause a greenhouse effect, it is environmentally friendly and cheaper than freons. These factors determine the use of this substance as a refrigerant.

Ammonia. It is used in medicine and in everyday life. This substance perfectly removes stains from clothes of various origins, and also neutralizes acids.

The use of ammonia in medicine

Ammonia is widely used in medicine as a 10% ammonia solution and is called ammonia. When a person faints, ammonia is brought to his senses. It is also used as an emetic. To do this, it is diluted and taken orally in small quantities. Especially popular is this method for alcohol poisoning. Lotions are made from ammonia and insect bites are treated. Surgeons use ammonia diluted in water to treat their hands.

It is important to remember that an overdose of ammonia is very dangerous. Pain in various organs, their swelling and even death are possible. This can be avoided if this substance is used for its intended purpose and with care!

Hydrogen nitride with the formula NH 3 is called ammonia. It is a light (lighter than air) gas with a pungent odour. The structure of the molecule determines the physical and chemical properties of ammonia.

Structure

The ammonia molecule consists of one nitrogen atom and three hydrogen atoms. The bonds between hydrogen and nitrogen atoms are covalent. The ammonia molecule has the shape of a trigonal pyramid.

There are three free electrons in the 2p orbital of nitrogen. Three hydrogen atoms enter into hybridization with them, forming the sp 3 hybridization type.

Rice. 1. The structure of the ammonia molecule.

If one hydrogen atom is replaced by a hydrocarbon radical (C n H m), a new organic substance, an amine, will be obtained. Not only one hydrogen atom can be replaced, but all three. Depending on the number of substituted atoms, there are three types of amines:

• primary(methylamine - CH 3 NH 2);
• secondary(dimethylamine - CH 3 -NH-CH 3);
• tertiary(trimethylamine - CH 3 -N- (CH 3) 2).

C 2 H 4, C 6 H 4, (C 2 H 4) 2 and other substances containing several carbon and hydrogen atoms can join the ammonia molecule.

Rice. 2. Formation of amines.

Ammonia and amines have a free pair of nitrogen electrons, so the properties of the two substances are similar.

Physical

The main physical properties of ammonia:

• colorless gas;
• Strong smell;
• good solubility in water (for one volume of water 700 volumes of ammonia at 20°C, at 0°C - 1200);
• lighter than air.

Ammonia liquefies at -33°C and becomes solid at -78°C. The concentrated solution contains 25% ammonia and has a density of 0.91 g/cm3. Liquid ammonia dissolves inorganic and organic substances, but does not conduct electricity.

In nature, ammonia is released during decay and decomposition of organic substances containing nitrogen (proteins, urea).

Chemical

The degree of oxidation of nitrogen in the composition of ammonia is -3, hydrogen - +1. When ammonia is formed, hydrogen oxidizes nitrogen, taking away three electrons from it. Due to the remaining pair of nitrogen electrons and the easy separation of hydrogen atoms, ammonia is an active compound that reacts with simple and complex substances.

The main chemical properties are described in the table.

Interaction	reaction products	The equation
With oxygen	Burns to form nitrogen or reacts with oxygen in the presence of a catalyst (platinum) to form nitric oxide	4NH 3 + 3O 2 → 2N 2 + 6H 2 O; 4NH 3 + 5O 2 → 4NO + 6H 2 O
With halogens	nitrogen, acid	2NH 3 + 3Br 2 → N 2 + 6HBr
	Ammonium hydroxide or ammonia	NH 3 + H 2 O → NH 4 OH
With acids	ammonium salts	NH 3 + HCl → NH 4 Cl; 2NH 3 + H 2 SO 4 → (NH 4) 2 SO 4
	Replaces the metal, forming a new salt	2NH 3 + CuSO 4 → (NH 4) 2 SO 4 + Cu
With metal oxides	Restores metal, nitrogen is formed	2NH 3 + 3CuO → 3Cu + N 2 + 3H 2 O

Rice. 3. Combustion of ammonia. Evaluation report

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Ammonia is a volatile hydrogen compound (hydrogen nitride) that plays a leading role in modern industry.

Although it was discovered only in the eighteenth century, it has been known to man since time immemorial. An aqueous solution of ammonia is ammonia. This substance is found in the decomposition products of living organisms and urine. Therefore, during the decay of organic matter (the remains of plants, animals), ammonia is released, and this gives rise to a sharp smell of decay (ammonia).

History of ammonia

Ammonia was discovered at the end of the eighteenth century by the British chemist Joseph Priestley, one of the founders of modern chemistry, who also made many important discoveries in other areas of science (physics, biology, optics).

For example, in the lists of his inventions there are: sparkling water, for which he received the medal of the Royal Society of London, and the well-known eraser (before, everyone used bread to erase graphite).

It is undeniable that Joseph Priestley made a huge contribution to chemistry, especially in the field of gases, but he made many of his achievements by accident.

Joseph Priestley obtained ammonia by heating ammonium chloride (ammonia) with calcium hydroxide (slaked lime) and then collecting the evolved gas in a mercury bath.

The mercury bath is a special device designed by Priestley to concentrate gases. At room temperature, mercury is a liquid with a high density, which does not allow it to absorb gases. Their scientist easily isolated from substances by heating over the surface of mercury.

Ammonia equation:

2NH 4 Cl + Ca(OH) 2 = NH 3 + CaCl 2.

After the discovery of ammonia by Joseph Priestley, his study did not stand still.

In 1784, the composition of this substance was established by the chemist Louis Berthollet, who decomposed it into its original elements by means of an electric discharge.

He received the name "ammonia" already in 1787 from the Latin name of ammonia, and the name "ammonia", which we are used to using, was introduced by Yakov Dmitrievich Zakharov in 1801.

But here's what's interesting. A hundred years before Joseph Priestley and his discovery of ammonia, scientist Robert Boyle observed a phenomenon in which a stick pre-soaked in hydrochloric acid began to smoke when it was brought near the gas released during the burning of manure. This is because the acid and ammonia reacted, and its products contained ammonium chloride, the particles of which created the smoke. It turns out that ammonia was detected by experimental methods a long time ago, but its presence in the world was proved much later.

Composition of the molecule

The ammonia molecule (NH 3) has the shape of a tetrahedron with a nitrogen atom at the top. It contains four electron clouds that overlap along the bond line, therefore, the molecule contains only sigma bonds. Compared to hydrogen, nitrogen has a higher electronegativity, so the common electron pairs in the molecule are shifted towards it. And since there are single bonds everywhere in ammonia, the type of hybridization is sp 3, and the angle between the electron clouds is 109 degrees.

How to get

About 100 million tons of ammonia are produced annually in the world, so this process can rightly be considered one of the most important in the world. It is released in liquid form or as a twenty-five percent solution.

There are the following ways to get it:

1. In industry, ammonia is produced through the synthesis of nitrogen and hydrogen, which is accompanied by the release of heat. Moreover, this reaction can take place only at high temperature, pressure and in the presence of a catalyst, which, while accelerating a weak reaction, does not itself enter into it.

Ammonia reaction equation:

N 2 + 3H 2 ⇄ 2NH 3 + Q

2. Ammonia can be obtained during coal coking.

In fact, there is no ammonia in coal, but there are many organic compounds in it, which contain nitrogen and hydrogen. And with strong heating of coal (pyrolysis), these components form ammonia, which comes out as a by-product.

3. In the laboratory, ammonia is produced by heating ammonium chloride and calcium hydroxide:

2NH 4 Cl + Ca(OH) 2 → CaCl 2 + 2NH 3 + 2H 2 O

4. Or by heating ammonium chloride with concentrated alkali:

NH 4 Cl + NaOH = NaCl + NH 3 + H 2 O

Application

Ammonia is an irreplaceable and really necessary substance, without which the world industry would slow down its movement. The scope of its application is wide: it is involved in all human production processes, from factories and laboratories to medicine. Its advantages are that it is environmentally friendly and is a fairly cheap product.

Applications of ammonia:

1. Chemical industry. It is used in the production of fertilizers, polymers, nitric acid, explosives, as a solvent (liquid ammonia).
2. Refrigeration units. Ammonia evaporates with the absorption of a large amount of heat from the environment, as it has certain thermodynamic properties. Refrigeration systems based on its use are more than efficient, which is why it is the main refrigerant in the industry.
3. The medicine. Ammonia or 10% ammonia solution is used when removing from fainting (irritation of the receptors of the nasal mucosa stimulates breathing), treating the surgeon's hands, inciting vomiting, and so on.
4. Textile industry. With its help, synthetic fibers are obtained. Ammonia is also used in cleaning or dyeing various fabrics.

Physical properties

Here are the physical properties of ammonia:

1. Under normal conditions, it is a gas.
2. Colorless.
3. Has a pungent odor.
4. Poisonous and highly toxic.
5. Let's very well dissolve in water (one volume of water on seven hundred volumes of ammonia) and a number of organic substances.
6. The melting point is -80 °C.
7. The boiling point is about -36 °C.
8. It is explosive and flammable.
9. About twice as light as air.
10. It has a molecular crystal lattice, respectively, it is fusible and fragile.
11. The molar mass of ammonia is 17 grams/mol.
12. When heated in an oxygen environment, it decomposes into water and nitrogen.

Chemical properties of ammonia

Ammonia is a strong reducing agent, since the oxidation state of nitrogen in the molecule is minimal. It is also capable of oxidizing properties, which happens much less frequently.

Reactions with ammonia:

• With acids, ammonia forms ammonium salts, which decompose when heated. With hydrochloric acid, ammonia forms ammonium chloride, and with sulfuric acid, ammonium sulfate.

NH 3 + HCL = NH 4 CL

NH 3 + H 2 SO4 \u003d (NH 4) 2 SO 4

• When heated, oxygen forms nitrogen, and with the participation of a catalyst (Pt), nitric oxide is obtained.

4NH 3 + 5O 2 \u003d 4NO + 6H 2 O

4NH 3 + 3O 2 \u003d 2N 2 + 6H 2 O

• An unstable ammonia hydrate is formed with water.

NH 3 + H 2 O \u003d NH 3 × H 2 O

Ammonia is capable of exhibiting alkaline properties, therefore, when interacting with water, it forms a weak base - NH 4 OH. But in fact, such a compound does not exist, so the formula should be written as follows: NH 3 × H 2 O.

with metal oxides.

2NH 3 + 3CuO \u003d 3Cu + N 2 + 3H 2 O

• with halogens.

8NH 3 + 3Cl 2 \u003d N 2 + 6NH 4 Cl

• with metal salts.

3NH 3 + ZN 2 O + AlCl 3 \u003d Al (OH) 3 ↓ + 3NH 4 Cl

Ammonia compounds

There are several types of complex substances formed when interacting with ammonia:

1. Ammonium salts. They are formed as a result of the reactions of ammonia with acids and decompose when heated.
2. Amides. These are salts that are obtained by acting on alkali metals with ammonia.
3. Hydrazine. This is a substance that is obtained as a result of the oxidation of ammonia with sodium hypochlorite in the presence of gelatin.
4. Amines. Ammonia reacts with haloalkanes as an addition reaction, forming salts.
5. Ammonia. Ammonia forms complex salts with silver and copper salts.

Biological role

Ammonia is a substance formed in the organisms of living beings during metabolism, which is a product of nitrogen metabolism in them. In animal physiology, an important role is assigned to it, but it has a high toxicity to organisms and is almost not contained in them in its pure form. Most of it is processed by the liver into a harmless substance - urea, or as it is also called urea.

It also helps to neutralize acids that enter the body with food, maintaining the acid-base balance of the blood.

Ammonia is an important source of nitrogen for plants. They mainly absorb it from the soil, but this is a very laborious and inefficient process. Some plants are able to accumulate nitrogen, which is contained in the atmosphere, with the help of special enzymes - nitrogenases. They then convert the nitrogen into compounds that are useful to them, such as proteins and amino acids.

Aggregate states

Ammonia can be in different states of aggregation:

1. It is present as a colorless gas with an unpleasant pungent odor under normal conditions.
2. Also, it can dissolve very well in water, so it can be stored as an aqueous solution with a certain concentration. It liquefies and becomes a liquid as a result of pressure and strong cooling.
3. Ammonia has a solid state in which it appears as colorless cubic crystals.

Ammonia poisoning

As mentioned above, ammonia is an extremely toxic and poisonous substance. It belongs to the fourth class of danger.

Poisoning with this gas is accompanied by a violation of many body processes:

• First, the nervous system is affected and oxygen uptake by nerve cells is reduced.
• When penetrating into the pharynx, then the trachea and bronchi, ammonia settles on the mucous membranes, dissolves, forming an alkali, which begins to adversely affect the body, causing internal burns, destroying tissues and cells.
• This substance also has a destructive effect on fatty components, which in one form or another are part of all human organs.
• The cardiovascular and endocrine systems fall under the influence, their work is disrupted.

After contact with ammonia, almost the entire human body, its internal tissues and organs suffer, and the life process worsens.

Most often, cases of poisoning with this gas occur in chemical industries as a result of its leakage, but they can also be poisoned at home, for example, if the container containing ammonia is not tightly closed and its vapors accumulate in the room.

Poisoning can occur even when, in a fainting state, a swab dipped in ammonia is brought to the nose of a person. If the victim is allowed to smell it for more than five seconds, then the risk of intoxication is high, so ammonia should always be handled with extreme caution.

Symptoms of poisoning

The following are some of the signs of ammonia poisoning:

1. Severe cough, difficulty breathing.
2. Burning in the eyes, tearing, pain reaction to bright light.
3. Burning in the mouth and nasopharynx.
4. Dizziness, headache.
5. Abdominal pain, vomiting.
6. Decreased hearing threshold.
7. With more serious poisoning, possible: loss of consciousness, convulsions, respiratory arrest, acute heart failure. The combination of violations can lead the victim into a coma.

Prevention in case of poisoning

First aid in this case consists of a few simple steps. First, you need to take the victim to fresh air, rinse his face and eyes with running water. Even those who were not very good in chemistry know from school: alkali is neutralized by acid, so the mouth and nose must be rinsed with water with the addition of lemon juice or vinegar.

If the poisoned person has lost consciousness, you should lay him on his side in case of vomiting, and if the pulse and breathing stop, do a heart massage and artificial respiration.

Consequences of poisoning

After ammonia intoxication, a person can expect very serious irreversible consequences. First of all, the central nervous system suffers, which entails a number of complications:

• The brain ceases to fully fulfill its functions and begins to malfunction, because of this, intelligence decreases, mental illness, amnesia, and nervous tics appear.
• The sensitivity of some parts of the body decreases.
• The work of the vestibular apparatus is disrupted. Because of this, a person feels constant dizziness.
• The organs of hearing begin to lose their working capacity, which leads to deafness.
• With the defeat of the eye covers, vision and its sharpness decrease, in the worst case, the victim will experience blindness.
• The onset of death. It depends on how high the concentration of gas in the air was and how much ammonia vapor entered the body.

To know and follow the prescribed safety measures means to protect yourself from the risk of a threat to your own life or the worst fate - disability, hearing or vision loss.

In everyday life, ammonia is often used, but they call it both ammonia and ammonia, remaining in full confidence that this is the same thing.

In fact, these are different substances that differ from each other in their origin, state of aggregation and chemical formulas. These three different substances are related only by a sharp ammonia smell.

The smell is the same, but the substances are different

In order to once and for all be convinced that ammonia and ammonia are one and the same, it is enough to turn to the history of their origin and look at their chemical formulas.

Ammonia is hydrogen nitride, a gas with a molar mass of 17 g/mol, the chemical formula is NH3.

Ammonia or ammonia is a liquid with the chemical formula NH4OH.

Ammonia is a salt with the chemical formula - NH4Cl.

Origin of ammonia

The history of the discovery of natural gas ammonia has two legends. According to the first legend, near the temple of the Egyptian god Amon, where religious rites were performed, people sniffed a pair of camel excrement, from which they fell into a trance. These pairs were named "ammonia".

According to the second legend, in northern Africa, in the area of ​​​​the oasis of Ammon, there was a crossroads of caravan routes. A huge number of animals passed there, the road was littered with their feces and plentifully watered with urine, which evaporated and released a gas that was called "ammonia".

As for the scientific discovery of a gas with the name "ammonia", it dates back to 1785. The chemical formula of the gas, NH3, was determined by the French scientist C. L. Berthollet and named it "ammonia".

But back in 1774, the English scientist D. Priestley received an identical gas, which he gave the name "alkaline air", but he could not deduce the chemical composition.

Ammonia (ammonia in Latin) is a colorless gas with a specific smell, lighter than air, chemically active, liquefies at a temperature of -33 C; dissolves well in water, has an alkaline reaction; interacts with hydrochloric acid and forms an ammonium salt: NH3 + HCl = NH4Cl, which decomposes when heated: NH4Cl = NH3 + HCl.

Ammonia is obtained in two ways - industrial and laboratory. In the laboratory method, ammonia is obtained by heating alkalis and ammonium salts:

• NH4Cl + KOH = NH3 + KCl + H2O;
• NH4 + + OH - = NH 3 + H2O.

In industrial conditions, ammonia is first produced in gaseous form, and then it is liquefied and brought to a 25% aqueous solution, which is called ammonia water.

The synthesis of ammonia is a very important chemical production, since ammonia is a fundamental element for many other chemical technologies and industries. Thus, ammonia is used in industrial refrigeration as a refrigerant; is a bleach in the processing and dyeing of fabrics; indispensable in the production of nitric acid, nitrogen fertilizers, ammonium salts, synthetic fibers - nylon and capron.

The industrial method for the synthesis of ammonia was invented in 1909 by the German chemist Fritz Haber. In 1918, for his discovery in chemistry, he received the Nobel Prize. The first ammonia plant was launched in 1913 in Germany, and in 1928 ammonia production was already established in Russia.

Origin of ammonia

Ammonia (Hammoniaci P. Sal) is a salt, the chemical formula is NH4Cl (ammonium chloride).

Ammonium chloride is of volcanic origin; found in hot springs, groundwater evaporation, in deposits of guano and native sulfur; Formed by burning coal seams or debris accumulations. It has the appearance of sagging, earthy deposits, crusts or massive skeletal crystalline accumulations, clusters and dendrites.

Pure ammonia is colorless or white, with a glassy sheen. Depending on the impurities present in it, the color can be all shades of yellow, brown, gray, different shades of red, brown.

When heated, ammonia is released from ammonia, it dissolves well in water. The solution tastes burning caustic - salty, the smell is sharp ammonia.

Ammonium chloride has been known to people since very ancient times and was used in ritual ceremonies, in the production and dyeing of fabrics, as well as by alchemists for soldering metals and melting gold.

In the Middle Ages, they learned how to get artificial ammonia from the horns and hooves of cattle, which was called the "spirit of a deer horn."

Origin of ammonia

Liquor ammonia caustici is its Latin name.

This is a 10% ammonia water solution with the chemical formula NH4OH; colorless transparent homogeneous mixture that can evaporate; with a specific smell of ammonia, which persists when frozen.

The mention of its use by Eastern alchemists dates back to the 8th century, and by European alchemists to the 13th century. Their records of the recipes they used have survived to this day.

Nowadays, they receive in an industrial and simple household way:

• in an industrial way, the synthesis is carried out from the gaseous state of hydrogen, nitrogen and air using certain catalysts, and then a water-alcohol solution is obtained, which has a sharp ammonia smell;
• a simple household method is based on diluting 25% ammonia water to a 10% solution.

Areas of use

The scope of ammonia and ammonia alcohol is wide, it is used in almost all spheres of human activity, from technological processes to medicine and domestic needs.

Application of ammonia

Ammonia is widely used as a refrigerant in various household and industrial equipment.

It is one of the most important products used in the chemical industry . In particular, it is used in the production of:

• ammonia;
• additives in building materials for use in frosty conditions;
• polymers, soda and nitric acid;
• fertilizers;
• explosives.

Use of ammonia alcohol

Ammonia alcohol is used in medicine and in everyday life.

Application in medicine is indicated in the following cases:

Use in everyday life consists in degreasing and cleaning various household utensils.

Alcohol solution at the rate of 2 tsp. for 2 cups of water and 1 tbsp. l. any dishwashing detergent can perfectly clean silverware, silver and gold jewelry (you cannot clean products with pearls with ammonia, it will become gray and cloudy). To do this, place silverware or jewelry in the solution, hold for 1 to 2 hours, then rinse in water and wipe dry.

It is good at removing blood, urine and sweat stains from wool, silk and lycra. A 50% solution is used as a stain remover. In concentrated form, it can remove pencil marks on clothes.

From carpets, upholstery and car covers, the heel can be removed with a solution of 1 tbsp. l. pure ammonia and 2 liters of hot water. To do this, clean the pollution and allow to dry. If necessary, you can re-clean.

Window glass, mirrors and faience can also be cleaned with a solution of 1 tbsp. l. pure ammonia and 3 tbsp. water. The surface will be clean and shiny.

Ammonia water 1 tbsp. l. in a mixture with 4 liters of water, stone deposits in the bath and washbasin can be cleaned. To do this, clean them with a solution, and then rinse with hot water.

Alcohol can be used in horticulture to control onion flies and aphids, and as a fertilizer for garden and indoor plants in acidic soil conditions.

Impact on a person

When using ammonia and ammonia, remember that that these are highly toxic substances and when using them, the dosage should be strictly observed and adhere to the terms of use.

If you intend to use ammonia, you must purchase it exclusively in pharmacies and carefully read the attached rules for using “Ammonia solution. Instructions for use".

Exceeding dosages can cause poisoning and serious health problems, as well as chemical burns. The rooms where it is used must be well ventilated.

In addition to toxicity, ammonia vapors are explosive. This happens when they are mixed with air in a certain proportion, so when working, special safety rules must be observed when working with explosives.

The first symptoms of poisoning may be:

• the appearance of red spots on the face and body;
• rapid breathing;
• general excitement.

Further signs of the development of poisoning are:

• the appearance of acute pain behind the sternum;
• convulsions;
• swelling of the larynx;
• spasm of the vocal cords;
• muscle weakness;
• circulatory disorders;
• semi-conscious state, up to loss of consciousness.

When ingesting ammonia water in excess doses, you may experience:

• diarrhea with false painful urges; burns of the esophagus, stomach and initial sections of the intestine;
• cough, lacrimation, salivation and sneezing;
• respiratory arrest of a reflex nature;
• vomiting with the smell of ammonia;
• taking ammonia alcohol in an amount of 10 to 15 grams. threatened with death.

If a person has an individual intolerance to the smell of ammonia, then even a slight ingestion of it through the respiratory tract or inside can immediately lead to the most adverse consequences.

If a person has a violation of the skin on the body in the form of weeping ulcers, eczema or dermatitis, then the use of lotions can lead to an even more extensive allergic reaction and burns of the skin.

First aid for poisoning

In cases of the first signs of poisoning with these substances, it is urgent to start providing first aid to the victim.

First aid measures include:

In case of more severe forms of poisoning, it is urgent to call an ambulance.

Ammonia alcohol is mandatory in first aid kits in first aid kits and should be at hand at the right time.

How much can it cost in pharmacies? The answer is very inexpensive. Get it, use it, but be extremely careful.

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