Use of nitric acid. Nitric acid and nitrates. Use in agriculture
: monohydrate (HNO 3 ·H 2 O) and trihydrate (HNO 3 ·3H 2 O).
Physical and physico-chemical properties
Phase diagram of an aqueous solution of nitric acid.
Nitrogen in nitric acid is tetravalent, oxidation state +5. Nitric acid is a colorless liquid that fumes in air, melting point −41.59 °C, boiling point +82.6 °C with partial decomposition. The solubility of nitric acid in water is not limited. Aqueous solutions of HNO 3 with a mass fraction of 0.95-0.98 are called “fuming nitric acid”, with a mass fraction of 0.6-0.7 - concentrated nitric acid. Forms an azeotropic mixture with water (mass fraction 68.4%, d 20 = 1.41 g/cm, T bp = 120.7 °C)
When crystallized from aqueous solutions, nitric acid forms crystalline hydrates:
- monohydrate HNO 3 H 2 O, T pl = −37.62 °C
- trihydrate HNO 3 3H 2 O, T pl = −18.47 °C
Solid nitric acid forms two crystalline modifications:
- monoclinic, space group P 2 1/a, a= 1.623 nm, b= 0.857 nm, c= 0.631, β = 90°, Z = 16;
The monohydrate forms crystals of the orthorhombic system, space group P na2, a= 0.631 nm, b= 0.869 nm, c= 0.544, Z = 4;
The density of aqueous solutions of nitric acid as a function of its concentration is described by the equation
where d is the density in g/cm³, c is the mass fraction of acid. This formula poorly describes the behavior of density at concentrations greater than 97%.
Chemical properties
Highly concentrated HNO 3 is usually brown in color due to the decomposition process that occurs in the light:
When heated, nitric acid decomposes according to the same reaction. Nitric acid can be distilled (without decomposition) only under reduced pressure (the indicated boiling point at atmospheric pressure is found by extrapolation).
c) displaces weak acids from their salts:
When boiling or exposed to light, nitric acid partially decomposes:
Nitric acid at any concentration exhibits the properties of an oxidizing acid, with nitrogen being reduced to an oxidation state from +4 to −3. The depth of reduction depends primarily on the nature of the reducing agent and the concentration of nitric acid. As an oxidizing acid, HNO 3 interacts:
Nitrates
Nitric acid is a strong acid. Its salts - nitrates - are obtained by the action of HNO 3 on metals, oxides, hydroxides or carbonates. All nitrates are highly soluble in water. Nitrate ion does not hydrolyze in water.
Salts of nitric acid decompose irreversibly when heated, and the composition of the decomposition products is determined by the cation:
a) nitrates of metals located in the voltage series to the left of magnesium:
b) nitrates of metals located in the voltage range between magnesium and copper:
c) nitrates of metals located in the voltage series to the right:
Nitrates in aqueous solutions exhibit practically no oxidizing properties, but at high temperatures in the solid state they are strong oxidizing agents, for example, when fusing solids:
Historical information
The method of obtaining dilute nitric acid by dry distillation of saltpeter with alum and copper sulfate was apparently first described in the treatises of Jabir (Geber in Latinized translations) in the 8th century. This method, with various modifications, the most significant of which was the replacement of copper sulfate with iron sulfate, was used in European and Arab alchemy until the 17th century.
In the 17th century, Glauber proposed a method for producing volatile acids by reacting their salts with concentrated sulfuric acid, including nitric acid from potassium nitrate, which made it possible to introduce concentrated nitric acid into chemical practice and study its properties. Method
Chemical properties of nitric acid
Nitric acid is characterized by properties: common with other acids and specific:
CHEMICAL PROPERTIES COMMON WITH OTHER ACIDS
1. Very strong acid. Indicators in its solution change color to red.
Dissociates almost completely in aqueous solution:
HNO 3 → H + + NO 3 -
Changes in indicator colors in acids2. Reacts with basic oxides
K 2 O + 2HNO 3 → 2KNO 3 + H 2 O
K 2 O + 2H + + 2NO 3 - → 2K + + 2NO 3 - + H 2 O
K 2 O + 2 H + → 2 K + + H 2 O
3. Reacts with bases
HNO 3 + NaOH → NaNO 3 + H 2 O
H + + NO 3 - + Na + + OH - → Na + + NO 3 - + H 2 O
H + + OH - → H 2 O
4. Reacts with salts, displaces weak acids from their salts
2HNO 3 + Na 2 CO 3 → 2NaNO 3 + H 2 O + CO 2
2H + + 2NO 3 - + 2Na + + C O 3 2- → 2Na + + 2NO 3 - + H 2 O + CO 2
2 H + + C O 3 2- → H 2 O + CO 2
SPECIFIC PROPERTIES OF NITRIC ACID
Nitric acid is a strong oxidizing agent
N +5 → N +4 → N +2 → N +1 → N o → N -3
N +5 + 8 e - → N -3 oxidizing agent, reduced.
1. Decomposes when exposed to light and heat
4HNO 3 t˚C → 2H 2 O + 4NO 2 + O 2
Brown gas is formed
2. Colors proteins orange-yellow. (in case of contact with the skin of the hands - "xanthoprotein reaction")
3. Reacts with metals.
Depending on the acid concentration and the position of the metal in N. Beketov’s electrochemical voltage series, different nitrogen-containing products can be formed.
Hydrogen is never released when interacting with metals
HNO 3 + Me= salt +H 2 O+ X
|
Alkaline and alkaline earth |
ASSIGNMENT TASKS No. 1. Carry out the transformations according to the scheme, name the substances, for UHR with * make an OM balance, and for** analyze RIO: NH 4 Cl**→ NH 3 * → N 2 → NO → NO 2 → HNO 3 → NO 2 No. 2. Carry out transformations according to the diagram (look carefully where the arrows are directed): Ammonium salt ←Ammonia ←Lithium nitride ←Nitrogen → Nitric oxide ( II )←Nitric acid For ORR, compile an e-balance; for RIO, complete ionic equations. No. 3. Write the reaction equations for the interaction of nitric acid with the following substances in molecular and ionic form: No. 4. Write down the equations, draw up an electronic balance, indicate the processes of oxidation and reduction, oxidizing agent and reducing agent: No. 5. Follow the link, study the information on the page and watch the video, click “watch experience”.
This is interesting: |
Introduction
You are interested in floriculture and came to the store to buy fertilizer for your flowers. While reviewing the various names and compositions, you noticed a bottle labeled “Nitrogen Fertilizer.” We read its composition: “Phosphorus, calcium, this and that... Nitric acid? What kind of animal is this?!” Usually one gets acquainted with nitric acid in such an environment. And many will then want to know more about it. Today I will try to satisfy your curiosity.
Definition
Nitric acid (formula HNO 3) is a strong monobasic acid. In an unoxidized state, it looks like in photo 1. Under normal conditions, it is a liquid, but it can be converted into a solid state of aggregation. And in it it resembles crystals having a monoclinic or rhombic lattice.
Chemical properties of nitric acid
It has the ability to mix well with water, where almost complete dissociation of this acid into ions occurs. Concentrated nitric acid is brown in color (photo). It is provided by the decomposition into nitrogen dioxide, water and oxygen, which occurs due to sunlight that falls on it. If you heat it up, the same decomposition will occur. All metals react with it, with the exception of tantalum, gold and platinoids (ruthenium, rhodium, palladium, iridium, osmium and platinum). However, its combination with hydrochloric acid can even dissolve some of them (this is the so-called “regia vodka”). Nitric acid, having any concentration, can act as an oxidizing agent. Many organic substances can spontaneously ignite when interacting with it. And some metals in this acid will be passivated. When exposed to them (as well as when reacting with oxides, carbonates and hydroxides), nitric acid forms its salts, called nitrates. The latter dissolve well in water. But nitrate ions are not hydrolyzed in it. If you heat the salts of this acid, their irreversible decomposition will occur.
Receipt
To produce nitric acid, synthetic ammonia is oxidized using platinum-rhodium catalysts to produce a mixture of nitrous gases, which are subsequently absorbed by water. It is also formed when potassium nitrate and iron sulfate are mixed and heated.
Application
Nitric acid is used to produce mineral fertilizers, explosives and some toxic substances. It is used to etch printing forms (etching boards, magnesium clichés, etc.), and also to acidify tinting solutions for photographs. Nitric acid is used to produce dyes and medicines, and it is also used to determine the presence of gold in gold alloys.
Physiological effects
Considering the degree of influence of nitric acid on the body, it is classified as hazard class 3 (moderately dangerous). Inhalation of its vapors leads to irritation of the respiratory tract. When nitric acid comes into contact with the skin, it leaves many long-healing ulcers. The areas of the skin where it gets in become a characteristic yellow color (photo). Scientifically speaking, a xanthoprotein reaction occurs. Nitrogen dioxide, which is produced when nitric acid is heated or decomposed in light, is very toxic and can cause pulmonary edema.
Conclusion
Nitric acid is beneficial to humans in both diluted and pure states. But most often it is found in substances, many of which are probably familiar to you (for example, nitroglycerin).
A monobasic strong acid, which is a colorless liquid under standard conditions, which turns yellow during storage, can be in a solid state, characterized by two crystalline modifications (monoclinic or rhombic lattice), at temperatures below minus 41.6 °C. This substance with the chemical formula - HNO3 - is called nitric acid. It has a molar mass of 63.0 g/mol, and its density corresponds to 1.51 g/cm³.
Nitric acid- corrosive, toxic substance and strong oxidizing agent. Since the Middle Ages, the name “strong water” (Aqua fortis) has been known. Alchemists who discovered the acid in the 13th century gave it this name, convinced of its extraordinary properties (it corroded all metals except gold), which were a million times greater than the strength of acetic acid, which in those days was considered the most active. But three centuries later it was found that even gold can be corroded by a mixture of acids such as nitric and hydrochloric in a volume ratio of 1:3, which for this reason was called “aqua regia.” The appearance of a yellow tint during storage is explained by the accumulation of nitrogen oxides in it. On sale, acid is often found with a concentration of 68%, and when the content of the main substance is more than 89%, it is called “fuming”.
Application of nitric acid
Nitric acid is widely used in industry to produce drugs, dyes, explosives, nitrogen fertilizers and nitric acid salts. In addition, it is used to dissolve metals (eg copper, lead, silver) that do not react with other acids. In jewelry it is used to determine gold in an alloy (this is the main method).
In organic synthesis, a mixture of concentrated nitric acid and sulfuric acid - a “nitrating mixture” - is widely used.
In metallurgy, nitric acid is used to dissolve and pickle metals, as well as to separate gold and silver. Nitric acid is also used in the chemical industry, in the production of explosives, and in the production of intermediates for the production of synthetic dyes and other chemicals.
Technical nitric acid is used in nickel plating, galvanizing and chrome plating of parts, as well as in the printing industry. Nitric acid is widely used in the dairy and electrical industries.
Preparation of nitric acid
Modern industrial methods for producing nitric acid are based on the catalytic oxidation of ammonia with atmospheric oxygen. When describing the properties of ammonia, it was indicated that it burns in oxygen, and the reaction products are water and free nitrogen. But in the presence of catalysts, the oxidation of ammonia with oxygen can proceed differently.
If a mixture of ammonia and air is passed over a catalyst, then at 750 °C and a certain composition of the mixture, almost complete conversion occurs. The resulting NO easily transforms into NO2, which, with water in the presence of atmospheric oxygen, produces nitric acid.
Platinum-based alloys are used as catalysts for the oxidation of ammonia. The nitric acid obtained by the oxidation of ammonia has a concentration not exceeding 60%. If necessary, it is concentrated. The industry produces diluted nitric acid with a concentration of 55, 47 and 45%, and concentrated nitric acid - 98 and 97.
Nitric acid- HNO3, oxygen-containing monobasic strong acid. Solid nitric acid forms two crystal modifications with monoclinic and orthorhombic lattices. Nitric acid mixes with water in any ratio. In aqueous solutions, it almost completely dissociates into ions. Forms an azeotropic mixture with water with a concentration of 68.4% and boiling point 120 °C at 1 atm. Two solid hydrates are known: monohydrate (HNO3 H2O) and trihydrate (HNO3 3H2O).
Highly concentrated HNO3 is usually brown in color due to the decomposition process that occurs in the light:
HNO3 ---> 4NO2 + O2 + 2H2O
When heated, nitric acid decomposes according to the same reaction. Nitric acid can be distilled (without decomposition) only under reduced pressure.
Nitric acid is strong oxidizing agent , concentrated nitric acid oxidizes sulfur to sulfuric acid, and phosphorus to phosphoric acid; some organic compounds (for example, amines and hydrazine, turpentine) spontaneously ignite upon contact with concentrated nitric acid.
The oxidation degree of nitrogen in nitric acid is 4-5. Acting as an oxidizing agent, HNO can be reduced to various products:
Which of these substances is formed, i.e., how deeply nitric acid is reduced in a given case, depends on the nature of the reducing agent and on the reaction conditions, primarily on the concentration of the acid. The higher the concentration of HNO, the less deeply it is reduced. When reacting with concentrated acid, it is most often released.
When reacting with dilute nitric acid with low-active metals, for example, with copper, NO is released. In the case of more active metals - iron, zinc - is formed.
Highly dilute nitric acid reacts with active metals-zinc, magnesium, aluminum - with the formation of ammonium ion, which gives ammonium nitrate with acid. Usually several products are formed simultaneously.
Gold, some platinum group metals and tantalum are inert to nitric acid over the entire concentration range, other metals react with it, the course of the reaction being determined by its concentration. Thus, concentrated nitric acid reacts with copper to form nitrogen dioxide, and dilute nitric acid (II):
Cu + 4HNO3----> Cu(NO3)2 + NO2 + 2H2O
3Cu + 8 HNO3 ----> 3Cu(NO3)2 + 2NO + 4H2O
Most metal c react with nitric acid to release nitrogen oxides in various oxidation states or mixtures thereof; dilute nitric acid, when reacting with active metals, can react to release hydrogen and reduce the nitrate ion to ammonia.
Some metals (iron, chromium, aluminum), which react with dilute nitric acid, are passivated by concentrated nitric acid and are resistant to its effects.
A mixture of nitric and sulfuric acids is called “melange”. Nitric acid is widely used to produce nitro compounds.
A mixture of three volumes of hydrochloric acid and one volume of nitric acid is called “aqua regia.” Aqua regia dissolves most metals, including gold. Its strong oxidizing abilities are due to the resulting atomic chlorine and nitrosyl chloride:
3HCl + HNO3 ----> NOCl + 2 =2H2O
Sulfuric acid– heavy oily liquid that has no color. Miscible with water in any ratio.
Concentrated sulfuric acidactively absorbs water from the air and removes it from other substances. When organic substances get into concentrated sulfuric acid, they become charred, for example, paper:
(C6H10O5)n + H2SO4 => H2SO4 + 5nH2O + 6C
When concentrated sulfuric acid reacts with sugar, a porous carbon mass is formed, similar to a black hardened sponge:
C12H22O11 + H2SO4 => C + H2O + CO2 + Q
Chemical properties of dilute and concentrated sulfuric acid are different.
Dilute solutions sulfuric acid react with metals , located in the electrochemical voltage series to the left of hydrogen, with the formation of sulfates and the release of hydrogen.
Concentrated solutions sulfuric acid exhibits strong oxidizing properties due to the presence in its molecules of a sulfur atom in the highest oxidation state (+6), therefore concentrated sulfuric acid is a strong oxidizing agent. This is how some nonmetals oxidize:
S + 2H2SO4 => 3SO2 + 2H2O
C + 2H2SO4 => CO2 + 2SO2 + 2H2O
P4 + 8H2SO4 => 4H3PO4 + 7SO2 + S + 2H2O
H2S + H2SO4 => S + SO2 + 2H2O
She interacts with metals , located in the electrochemical voltage series of metals to the right of hydrogen (copper, silver, mercury), with the formation of sulfates, water and sulfur reduction products. Concentrated solutions sulfuric acid don't react with gold and platinum due to their low activity.
a) low-active metals reduce sulfuric acid to sulfur dioxide SO2:
Cu + 2H2SO4 => CuSO4 + SO2 + 2H2O
2Ag + 2H2SO4 => Ag2SO4 + SO2 + 2H2O
b) with metals of intermediate activity, reactions are possible with the release of any of the three products of the reduction of sulfuric acid:
Zn + 2H2SO4 => ZnSO4 + SO2 + 2H2O
3Zn + 4H2SO4 => 3ZnSO4 + S + 4H2O
4Zn + 5H2SO4 => 4ZnSO4 + H2S + 2H2O
c) sulfur or hydrogen sulfide can be released with active metals:
8K + 5H2SO4 => 4K2SO4 + H2S + 4H2O
6Na + 4H2SO4 => 3Na2SO4 + S + 4H2O
d) concentrated sulfuric acid does not interact with aluminum, iron, chromium, cobalt, nickel in the cold (that is, without heating) - passivation of these metals occurs. Therefore, sulfuric acid can be transported in iron containers. However, when heated, both iron and aluminum can interact with it:
2Fe + 6H2SO4 => Fe2(SO4)3 + 3SO2 + 6H2O
2Al + 6H2SO4 => Al2(SO4)3 + 3SO2 + 6H2O
THAT. the depth of sulfur reduction depends on the reducing properties of metals. Active metals (sodium, potassium, lithium) reduce sulfuric acid to hydrogen sulfide, metals located in the voltage range from aluminum to iron - to free sulfur, and metals with less activity - to sulfur dioxide.
Obtaining acids.
1. Oxygen-free acids are obtained by synthesizing hydrogen compounds of non-metals from simple substances and then dissolving the resulting products in water
Non-metal + H 2 = Hydrogen bond of non-metal
H2 + Cl2 = 2HCl
2. Oxoacids are obtained by reacting acid oxides with water.
Acidic oxide + H 2 O = Oxoacid
SO 3 + H 2 O = H 2 SO 4
3. Most acids can be obtained by reacting salts with acids.
Salt + Acid = Salt + Acid
2NaCl + H 2 SO 4 = 2HCl + Na 2 SO 4
Bases are complex substances whose molecules consist of a metal atom and one or more hydroxide groups.
Bases are electrolytes that dissociate to form metal element cations and hydroxide anions.
For example:
KON = K +1 + OH -1
6.Classification of grounds:
1.By the number of hydroxyl groups in the molecule:
a) · Monoacid, the molecules of which contain one hydroxide group.
b) · Diacids, the molecules of which contain two hydroxide groups.
c) · Triacids, the molecules of which contain three hydroxide groups.
2. According to solubility in water: Soluble and Insoluble.
7.Physical properties of bases:
All inorganic bases are solids (except ammonium hydroxide). The bases have different colors: potassium hydroxide is white, copper hydroxide is blue, iron hydroxide is red-brown.
Soluble grounds form solutions that feel soapy to the touch, which is how these substances got their name alkali.
Alkalis form only 10 elements of D.I. Mendeleev’s periodic system of chemical elements: 6 alkali metals - lithium, sodium, potassium, rubidium, cesium, francium and 4 alkaline earth metals - calcium, strontium, barium, radium.
8. Chemical properties of bases:
1. Aqueous solutions of alkalis change the color of indicators. phenolphthalein - crimson, methyl orange - yellow. This is ensured by the free presence of hydroxo groups in the solution. That is why poorly soluble bases do not give such a reaction.
2. Interact :
a) with acids: Base + Acid = Salt + H 2 O
KOH + HCl = KCl + H2O
b) with acid oxides: Alkali + Acid oxide = Salt + H 2 O
Ca(OH) 2 + CO 2 = CaCO 3 + H 2 O
c) with solutions: Lye solution + Salt solution = New base + New salt
2NaOH + CuSO 4 = Cu(OH) 2 + Na 2 SO 4
d) with amphoteric metals: Zn + 2NaOH = Na 2 ZnO 2 + H 2
Amphoteric hydroxides:
a) React with acids to form salt and water:
Copper(II) hydroxide + 2HBr = CuBr2 + water.
b). React with alkalis: result - salt and water (condition: fusion):
Zn(OH)2 + 2CsOH = salt + 2H2O.
V). React with strong hydroxides: the result is salts if the reaction occurs in an aqueous solution: Cr(OH)3 + 3RbOH = Rb3
When heated, bases that are insoluble in water decompose into the basic oxide and water:
Insoluble Base = Basic Oxide + H2O
Cu(OH) 2 = CuO + H 2 O
Salts – these are products of incomplete replacement of hydrogen atoms in acid molecules with metal atoms or these are products of replacement of hydroxide groups in base molecules with acidic residues .
Salts- these are electrolytes that dissociate to form cations of the metal element and anions of the acid residue.
For example:
K 2 CO 3 = 2K +1 + CO 3 2-
Classification:
Normal salts. These are the products of complete replacement of hydrogen atoms in an acid molecule with non-metal atoms, or the products of complete replacement of hydroxide groups in a base molecule with acidic residues.
Acid salts. These are products of incomplete replacement of hydrogen atoms in the molecules of polybasic acids with metal atoms.
Basic salts. These are products of incomplete replacement of hydroxide groups in molecules of polyacid bases with acidic residues.
Types of salts:
Double salts- they contain two different cations; they are obtained by crystallization from a mixed solution of salts with different cations, but the same anions.
Mixed salts- they contain two different anions.
Hydrate salts(crystalline hydrates) - they contain molecules of water of crystallization.
Complex salts- they contain a complex cation or a complex anion.
A special group consists of salts of organic acids, the properties of which differ significantly from the properties of mineral salts. Some of them can be classified as a special class of organic salts, so-called ionic liquids or otherwise “liquid salts,” organic salts with a melting point below 100 °C.
Physical properties:
Most salts are white solids. Some salts are colored. For example, potassium orange dichromate, green nickel sulfate.
According to solubility in water salts are divided into soluble in water, slightly soluble in water and insoluble.
Chemical properties:
Soluble salts in aqueous solutions dissociate into ions:
1. Medium salts dissociate into metal cations and anions of acid residues:
Acid salts dissociate into metal cations and complex anions:
KHSO 3 = K + HSO 3
· Basic metals dissociate into complex cations and anions of acidic residues:
AlOH(CH 3 COO) 2 = AlOH + 2CH 3 COO
2. Salts interact with metals to form a new salt and a new metal: Me(1) + Salt(1) = Me(2) + Salt(2)
CuSO 4 + Fe = FeSO 4 + Cu
3. Solutions interact with alkalis Salt solution + alkali solution = New salt + New base:
FeCl 3 + 3KOH = Fe(OH) 3 + 3KCl
4. Salts interact with acids Salt + Acid = Salt + Acid:
BaCl 2 + H 2 SO 4 = BaSO 4 + 2HCl
5. Salts can interact with each other Salt(1) + Salt(2) = Salt(3) + Salt(4):
AgNO 3 + KCl = AgCl + KNO 3
6. Basic salts interact with acids Basic salt + Acid = Medium salt + H 2 O:
CuOHCl + HCl = CuCl 2 + H 2 O
7. Acid salts interact with alkalis Acid salt + Alkali = Medium salt + H 2 O:
NaHSO 3 + NaOH = Na 2 SO 3 + H 2 O
8. Many salts decompose when heated: MgCO 3 = MgO + CO 2
Representatives of salts and their meaning:
Salts are widely used both in production and in everyday life:
Salts of hydrochloric acid. The most commonly used chlorides are sodium chloride and potassium chloride.
Sodium chloride (table salt) is isolated from lake and sea water, and is also mined in salt mines. Table salt is used for food. In industry, sodium chloride serves as a raw material for the production of chlorine, sodium hydroxide and soda.
Potassium chloride is used in agriculture as potassium fertilizer.
Salts of sulfuric acid. In construction and medicine, semi-aqueous gypsum, obtained by firing rock (calcium sulfate dihydrate), is widely used. When mixed with water, it quickly hardens to form calcium sulfate dihydrate, that is, gypsum.
Sodium sulfate decahydrate is used as a raw material for the production of soda.
Salts of nitric acid. Nitrates are mostly used as fertilizers in agriculture. The most important of them are sodium nitrate, potassium nitrate, calcium nitrate and ammonium nitrate. Usually these salts are called nitrate.
Of the orthophosphates, the most important is calcium orthophosphate. This salt serves as the main component of minerals - phosphorites and apatites. Phosphorites and apatites are used as raw materials in the production of phosphate fertilizers, such as superphosphate and precipitate.
Salts of carbonic acid. Calcium carbonate is used as a raw material to produce lime.
Sodium carbonate (soda) is used in glass production and in soap making.
- Calcium carbonate is also found in nature in the form of limestone, chalk and marble.
The material world in which we live and of which we are a tiny part is one and at the same time infinitely diverse. The unity and diversity of the chemical substances of this world is most clearly manifested in the genetic connection of substances, which is reflected in the so-called genetic series.
Genetic call the connection between substances of different classes based on their mutual transformations.
If the basis of the genetic series in inorganic chemistry is made up of substances formed by one chemical element, then the basis of the genetic series in organic chemistry (chemistry of carbon compounds) is made up of substances with the same number of carbon atoms in the molecule.
Knowledge control:
1. Define salts, bases, acids, their characteristics, main characteristic reactions.
2.Why are acids and bases combined into the group hydroxides? What do they have in common and how are they different? Why does alkali need to be added to a solution of aluminum salt, and not vice versa?
3. Assignment: Give examples of reaction equations illustrating these general properties of insoluble bases.
4. Task: Determine the oxidation state of atoms of metallic elements in the given formulas. What pattern can be observed between their oxidation states in the oxide and the base?
HOMEWORK:
Work through: L2.pp.162-172, retelling of lecture notes No. 5.
Write down the equations of possible reactions according to the diagrams, indicate the types of reactions: a) HCl + CaO ... ;
b) HCl + Al(OH) 3 ...;
c) Mg + HCl ... ;
d) Hg + HCl ... .
Divide substances into classes of compounds. Formulas of substances: H 2 SO 4, NaOH, CuCl 2, Na 2 SO 4, CaO, SO 3, H 3 PO 4, Fe(OH) 3, AgNO 3, Mg(OH) 2, HCl, ZnO, CO 2, Cu 2 O, NO 2
Lecture No. 6.
Topic: Metals. Position of metal elements in the periodic table. Finding metals in nature. Metals. Interaction of metals with non-metals (chlorine, sulfur and oxygen).
Equipment: periodic table of chemical elements, collection of metals, activity series of metals.
Topic study plan
(list of questions required to study):
1. The position of elements - metals in the periodic table, the structure of their atoms.
2. Metals as simple substances. Metal bond, metal crystal lattices.
3. General physical properties of metals.
4. The prevalence of metal elements and their compounds in nature.
5. Chemical properties of metal elements.
6. The concept of corrosion.
Loading...