Summary of a chemistry lesson in the 9th grade on the topic "Oxygen compounds of nitrogen" according to the educational and methodological complex of O.S. Gabrielyan. The work aims to consider the oxidative-connective properties of nitrogen ions using the example of oxygen compounds. The abstract contains educational, developmental, educational and health-preserving tasks.
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Oxygen compounds of nitrogen.
Nitrogen oxides. Nitrogen forms six oxygen compounds. oxidation states + 1 N 2 O + 2 NO + 3 N 2 O 3 + 4 NO 2, N 2 O 4 + 5 N 2 O 5
Preparation: NH 4 NO = N 2 O +2H 2 O Chemical properties: 1. decomposition when heating 2 N 2 +1 O = 2 N 2 0 + O 2 2. with hydrogen N 2 +1 O + H 2 = N 2 0 + H 2 O non-salt-forming +1 N 2 O nitric oxide (I), nitrous oxide or “laughing gas”, has a stimulating effect on the human nervous system and is used in medicine as an anesthetic. Physical properties: gas, colorless and odorless. Exhibits oxidizing properties and easily decomposes.
NO +2 Preparation: 1. In nature: N 2 + O 2 = 2NO 2. In industry: 4 NH 3 + 5O 2 = 4NO +6H 2 O Chemical properties: 1. easily oxidized: 2 N +2 O + O 2 = 2N +4 O 2 2. oxidizing agent: 2 N +2 O + 2SO 2 = 2SO 3 +N 2 0 non-salt-forming colorless gas, thermally stable, poorly soluble in water, reacts almost instantly with oxygen (at room temperature).
N 2 O 3 +3 Chemical properties: NO 2 + NO N 2 O 3 Preparation: ALL properties of acid oxides. acid oxide is a dark blue liquid, thermally unstable, boiling point = 3.5 0C, i.e. it exists in a liquid state only when cooled, under normal conditions it turns into a gaseous state. When interacting with water, nitrous acid is formed.
NO 2 + 4 Preparation: 1. 2 NO + O 2 = 2NO 2 2. Cu + 4HNO 3(k) = Cu(NO 3) 2 + 2NO 2 + 2H 2 O Chemical properties: 1. with water 2 NO 2 + H 2 O = HNO 3 + HNO 2 2. with alkalis 2NO 2 + 2NaOH = NaNO 3 + NaNO 2 + H 2 O 3. dimerization 2NO 2 N 2 O 4 toxic nitric oxide (IV) or nitrogen dioxide, brown gas, good soluble in water, completely reacts with it. Is a strong oxidizing agent.
N 2 O 5 + 5 Preparation: 1. 2NO 2 + O 3 = N 2 O 5 + O 2 2. 2HNO 3 + P 2 O 5 = 2HPO 3 + N 2 O 5 Chemical properties: 1. easily decomposes 2N 2 O 5 = 4NO 2 + O 2 2. strong oxidizing agent, acidic oxide, nitric oxide (V), nitric anhydride, white solid (melting point = 41 0 C). It exhibits acidic properties and is a very strong oxidizing agent.
HNO 3 Composition. Structure. Properties. H O N O O - - degree of oxidation of nitrogen nitrogen valence +5 IV chemical bond covalent polar Nitric acid is a colorless hygroscopic liquid, with a pungent odor, “smoke” in air, unlimitedly soluble in water. Melting point −41.59 °C, boiling point +82.6 °C with partial decomposition. When stored in light, it decomposes into nitric oxide (IV), oxygen and water, acquiring a yellowish color: 4HNO 3 = 4NO 2 + O 2 + 2H 2 O Nitric acid is poisonous.
Nitric acid (HNO 3) Classification according to: presence of oxygen: basicity: solubility in water: volatility: degree of electrolytic dissociation: oxygen-containing monobasic soluble volatile strong
Production of nitric acid in industry NH 3 NO NO 2 HNO 3 4NH 3 + 5O 2 = 4NO + 6H 2 O 2NO+O 2 = 2NO 2 4 NO 2 + 2 H 2 O + O 2 = 4 HNO 3 Contact oxidation of ammonia to oxide nitrogen (II): 2. Oxidation of nitric oxide (II) to nitric oxide (IV): 3. Adsorption (absorption) of nitric oxide (IV) by water in excess of oxygen
In the laboratory, nitric acid is prepared by reacting concentrated sulfuric acid with nitrates under low heat. NaNO 3 + H 2 SO 4 = NaHSO 4 + HNO 3
Chemical properties of nitric acid Nitric acid exhibits all the typical properties of acids. 1 . Properties of HNO 3 as an electrolyte: 1 3 2 3 2) with basic and amphoteric oxides 3) with bases 1) Dissociation: HNO 3 = H + + NO 3 – 2HNO 3 + CuO = Cu(NO 3) 2 + H 2 O 6HNO 3 + Al 2 O 3 = 2Al(NO 3) 3 + 3H 2 O HNO 3 + NaOH = NaNO 3 + H 2 O 2HNO 3 + Zn(OH) 2 = Zn(NO 3) 2 + 2H 2 O 4) s salts 2HNO 3 + Na 2 SiO 3 = H 2 SiO 3 ↓ + 2NaNO 3
2. Oxidizing properties: features of interaction with metals: (nitric acid never releases hydrogen!) Me + HNO 3 = Me(NO 3) 2 + H 2 ￪ Metal Concentrated (> 60%) Dilute (5-60%) Very diluted (
With metals in the voltage series to the left of hydrogen: With metals in the voltage series to the right of hydrogen: Concentrated HNO 3 Dilute HNO 3 Chemical properties of nitric acid
2. Oxidizing properties 2) Features of interaction with non-metals (S, P, C): 3) Interacts with organic substances (turpentine flares up): Chemical properties of nitric acid 3P + 5HNO 3 + H 2 O = 3H 3 PO 4 + 5NO C + 4HNO 3 = CO 2 + H 2 O + 4NO 2 5 HNO 3 + 3 P + 2 H 2 O → 3 H 3 PO 4 + 5 NO
Application of nitric acid 1 5 4 6 2 3 Production of nitrogen and complex fertilizers. Production of explosives Production of dyes Production of drugs Production of films, nitro-varnishes, nitro-enamels Production of artificial fibers 7 As a component of a nitrating mixture, for trawling metals in metallurgy
Nitrates are salts of nitric acid, obtained by the action of acid on metals, their oxides and hydroxides. Nitrate is a salt of nitric acid and alkali metals. NaNO 3 – sodium nitrate KNO 3 – potassium nitrate NH 4 NO 3 – ammonium nitrate Ca (NO 3) 2 – calcium nitrate Properties: ALL are soluble in water.
When heated, nitrates decompose the more completely the more to the right the metal forming the salt is in the electrochemical voltage series. Li K Ba Ca Na Mg Al Mn Zn Cr Fe Co Sn Pb Cu Ag Hg Au nitrite + O 2 metal oxide + NO 2 + O 2 Me + NO 2 + O 2 2NaNO 3 = 2NaNO 2 + O 2 2Pb(NO 3) 2 = 2PbO + 4NO 2 + O 2 2AgNO 3 = 2Ag + 2NO 2 + O 2
Nitrate is used as fertilizer. KNO 3 is used to prepare black powder.
Homework: § 26, ex. 2.4 p. 121.
Sections: Chemistry
The use of electronic publications in the educational process greatly facilitates the conduct of a lesson, allows the use of an individual, differentiated approach when providing feedback between a student and a teacher, and provides significant assistance to the teacher in preparing for a lesson.
If in computer science lessons the computer acts as the goal of the educational process, then in other lessons, in particular in chemistry lessons, the computer is a means of achieving educational goals.
The traditional tool of the teacher and student in the lesson: blackboard, chalk, pen, notebook, today the tools appear in a new version, for example, as an electronic SMART board.
Interactive lessons allow you to increase the intensity of the lesson:
- reduce the time that a teacher spends on writing on the board during a regular lesson,
- allows you to return to the previous slide if the child missed some point in the lesson;
- increase the child’s interest in presenting the material, as it involves all the child’s senses in the lesson,
- make lesson material available to those children who missed the lesson for some reason.
Lesson objectives:
Educational: consolidate students' knowledge about nitrogen oxides, repeat the classification and basic properties of oxides, repeat the basic properties of nitric acid and consolidate the specifics of its interaction with metals, familiarize them with the use of nitric acid.
Developmental: development of skills to independently systematize and analyze theoretical and experimental information, highlight the main thing in the process of demonstrating experiments, be able to independently draw conclusions, learn to use analogies.
Educational: the formation of a scientific worldview, the development of communication skills in the course of group, pair and collective work, the conviction of the need to use new information technologies to involve chemistry in understanding and describing the processes occurring in the environment, cultivating a conscious attitude towards one’s health and the “health” of the environment .
Lesson form– seminar
Methods used in the lesson – verbal (conversation, story), visual (presentation), practical (virtual chemical laboratory), novelty (use of an interactive whiteboard), control (oral questioning, writing equations of chemical reactions).
Equipment and materials:
- computer
- electronic SMART board.
- presentation “Oxygen compounds of nitrogen”
Disc “Virtual Chemical Laboratory”, 9th grade
1. Organizational stage. Teacher's opening speech: Greeting, checking readiness for the lesson.
2. Motivational stage
The topic of the lesson is a logical continuation of the study of nitrogen compounds.
- Strengthen your knowledge of nitrogen oxides
- Nitric oxide (IV) is one of the causes of acid rain
- Review of the general properties of nitric acid
- Visiting a virtual chemical laboratory and performing chemical reactions demonstrating the peculiarities of the interaction of nitric acid with non-metals and metals
- Learn about the uses of nitric acid
The stage of expansion, generalization, consolidation of students’ theoretical and practical knowledge on the topic of the lesson
What nitrogen oxides do you know? Name each oxide
Indicate the valence and oxidation state of nitrogen in each oxide
What type of oxide does each compound belong to?
Students take turns going to the board and writing on the electronic SMART board the chemical formulas of nitrogen oxides, indicating the valence and oxidation state of nitrogen in each compound, giving the name of the oxides, and indicating the type of each compound.
What are the physical and chemical properties of nitric oxide (I)? (Slide 5)
What are the physical and chemical properties of nitric oxide (II)? (Slide 6)
Complete the equations of chemical reactions characteristic of this oxide
What are the physical and chemical properties of nitric oxide (III)? (Slide 7)
Complete the equations of chemical reactions characteristic of this oxide
N 2 O 3 + H 2 O =
What are the physical and chemical properties of nitric oxide (IV)? (Slide 8)
Complete the equations of chemical reactions characteristic of this oxide
The appearance of an ever-increasing amount of nitrogen oxide (IV), which is part of the exhaust gases of cars and gas emissions from industrial enterprises, is the cause of acid rain.
What are the physical and chemical properties of nitric oxide (V)? (Slide 9)
Complete the equations of chemical reactions characteristic of this oxide
N 2 O 5 + H 2 O =
In what ways can all nitrogen oxides be obtained? Write equations for chemical reactions. Students go to the interactive whiteboard and write reaction equations. (Slide 10)
What nitrogen acids do you know? Compare these acids.
| Comparison options | Nitrous acid | Nitric acid |
| Chemical formula | HNO2 | HNO3 |
| Nitrogen oxidation degree | + 3 | +5 |
| Nitrogen valence | 3 | 4 |
| Boiling temperature | - | 82.6 0 С |
| Sustainability | Exists only at low temperatures and in dilute solutions; when the temperature rises, it easily decomposes: 3 HNO 2 = HNO 3 + 2NO + H 2 O |
Decomposes in light 4HNO 3 =4 NO 2 + O2+2H2O |
| Chemical properties | Shows oxidizing and reducing properties | Shows only oxidizing properties |
In the eyes of ancient researchers, nitric acid is a liquid that has great power in human hands. (Slide 12)
Complete the equations of chemical reactions: (Slide 13)
HNO3 + Mg(OH)2 =
HNO 3 + Na 2 CO 3 =
HNO 3 + K 2 SiO 3 =
Check the equations of chemical reactions: (Slide 14)
2HNO 3 + Mg(OH) 2 -> Mg(NO 3) 2 +2H 2 O
2HNO 3 + MgO -> Mg(NO 3) 2 +2H 2 O
2HNO 3 + Na 2 CO 3 -> 2NaNO 3 +CO 2 +H 2 O
2HNO 3 + K 2 SiO 3 -> 2KNO 3 + H 2 SiO 3?
Features of the interaction of nitric acid with metals. (Slide 15)
Students answer the question:
When nitric acid interacts with metals, the following is formed: salt (Me nitrate) + H 2 O + A, where “A” is the reduction product of N +5: NO 2, N 2 O 3, NO, N 2 O, N 2, NH 3 (NH 4 NO 3);
Metals that come before and after hydrogen in the activity series interact with nitric acid; the more active the metal and the dilute the acid, the deeper the reduction of the nitrogen atom in nitric acid.
Nitric acid (concentrated) does not interact (passivates): Al, Fe, Cr, Ni, Pb, etc.
The interaction of nitric acid with metals and non-metals is confirmed by demonstration experiments that students perform using a virtual chemical laboratory disk. Reaction equations for the interaction of nitric acid with metals and non-metals are written by students on an electronic SMART board. (Slides 16,17)
Nitric acid has a wide range of uses. The use of nitric acid has two faces: creative and destructive. Nitric acid is used to produce nitrogen fertilizers, explosives, dyes, plastics, artificial fibers, etc. (Slides 18-21)
After the seminar, you can conduct a ten-minute test, the questions of which are in the presentation.
4. Summing up. Reflection.
We have worked effectively with you. Do you think we have achieved our goals? What was difficult for you? What was the easiest for you?
Write equations for the chemical reactions of producing nitric acid from atmospheric nitrogen.
Nitric oxide (I) N 2 O N 2 O – nitric oxide (I), nitrous oxide or “laughing gas”, has a stimulating effect on the human nervous system and is used in medicine as an anesthetic. Physical properties: gas, colorless and odorless. Exhibits oxidizing properties and easily decomposes. Non-salt-forming oxide. 2N 2 O= N 2 O + Cu=
Nitrogen oxide (III) N 2 O 3 – nitrogen oxide (III) is a dark blue liquid, thermally unstable, boiling point = 3.5 0C, i.e. it exists in a liquid state only when cooled, under normal conditions it turns into gaseous state. An acidic oxide that reacts with water to form nitrous acid. N 2 O 3 = N 2 O 3 + H 2 O =
Nitric acid. HNO 3 Nitric acid is a colorless hygroscopic liquid, has a pungent odor, “smoke” in air, is indefinitely soluble in water, boiling point = C. Solutions of nitric acid are stored in a dark glass jar, i.e. it decomposes in light: 4HNO 3 = 4NO 2 +2H 2 O+O 2
"Carbon Monoxide IV" - Soon the water will become cloudy. Physical properties of CO2. Dry ice, unlike water ice, is dense. Non-toxic, does not conduct electrical current. Application of carbon monoxide (IV). Dry ice is also CO2. A gas needed by plants for photosynthesis. In nature. The carbon dioxide content in the atmosphere is relatively low, 0.04 - 0.03.
“Nitrogen oxide” - 2. The cylinder with nitrogen (II) oxide was closed with a plate. Oxidizing agent: 2NO + 2SO2 = 2SO3 + N2 Nitrous method for producing sulfuric acid. 1. There are three closed cylinders: with nitrogen oxide (IV), with nitrogen, with ammonia. No-nitric oxide (II). It dissolves well in water. N2O5. All nitrogen oxides, except N2O, are toxic substances.
“Decomposition of oxides” - Classification of oxides. Basic oxides. Oxides. Amphoteric oxides. Acidic oxides. Glossary. Indifferent oxides (non-salt-forming). Classification Table of contents. Tasks. A manual for students.
"Oxides" - In nature. Metal ores. CHROME OXIDE cr2o3. The carbon dioxide content in the atmosphere is relatively low, only 0.04-0.03%. Whitewashed. For example: red, magnetic and brown iron ores, bauxite (aluminum oxide), Gas needed by plants for photosynthesis. Carbon monoxide (II) CO. Titanium (IV) oxide – TiO2 – has the same valuable properties.
“Carbon monoxide” - Carbon monoxide (II) is characterized by reducing properties. or carbon dioxide is a colorless and odorless gas. So. Carbon monoxide (II). Carbon monoxide (IV). Obtaining carbon monoxide (IV). Used COR: Demonstration lesson planning. Carbon oxides.
“Chemical oxides” - Substances that contain oxygen. Quartz sand. H2O. Carbon monoxide (IV). Oxides are complex substances. Bauxite. Olive green paint pigment. Quicklime. Metal oxides. Oxides. Carbon monoxide (II).
There are a total of 14 presentations in the topic
