Alkali metals group 1 presentation. Presentation on the topic: Alkali metals. in free form
Galtseva O.N. Chemistry teacher MBOU "Anninskaya Secondary School with UIOP"
Lesson topic: MetalsIA-groups of the Periodic Table and the simple substances they form
The purpose of the lesson: To develop the cognitive interest of students and intensify their cognitive activity when studying elementsIA-groups, their physical and chemical properties.
Planned learning outcomes .
Subject.Knowledge of the features of the electronic structure of alkali metal atoms, their physical and chemical properties; the ability to express knowledge of chemical properties through the preparation of appropriate equations of chemical reactions; ability to observe and describe chemical experiments.
Metasubject.The ability to define concepts, generalize, establish analogies, classify, independently select grounds and criteria for classification, establish cause-and-effect relationships, build logical reasoning, and draw conclusions.
Personal.Formation of a holistic worldview corresponding to the modern level of development of science.
Basic Concepts: alkali metals, atomic structure, type of crystal lattice, oxides, peroxides.
Demonstrations: Periodic table of chemical elements D.I. Mendeleev, metals lithium and sodium, experiment on the interaction of lithium and sodium with water.
| Lesson steps | Teacher activities | Student activity |
| Updating knowledge | Slide number 2. Repetition of the general characteristics of metals on the questions “Remove the excess” | They comment on the slide and “remove unnecessary things” that are not related to metals. Repeat the general characteristics of metals |
| Learning new material | Slide number 3. Compilation of comparative characteristics of alkali metals, changes in the properties of metals in a group depending on the structure of atoms | Fill out the table yourself. Using the completed table, a comparative description of alkali metals is given. |
| Slide 4. Metals in nature. Questions: What groups are metals divided into according to their occurrence in nature? What group do alkali metals belong to? How can I get them? Teacher explanation about the electrolysis process using slide animation. | From the previous lesson they give information in what form metals are found in nature. They answer the question about what form alkali metals occur in nature and how they can be obtained. |
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| Slide 5. Physical properties of alkali metals. Questions: What is the crystal lattice of metals? What properties of metals depend on this type of crystal lattice? What properties of alkali metals can you assume? Demonstration of lithium and sodium. | Answer the teacher's questions based on information received about the general characteristics of metals. It is assumed what physical properties alkali metals have. |
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| Slide 6. Chemical properties of alkali metals. Demonstration of the chemical reaction of lithium and sodium with water. Questions: How to explain the phenomena occurring in a demonstration experiment? Why did sodium react faster than lithium? What other chemical properties do alkali metals have? | They assume what properties alkali metals may have based on the general properties of metals. Observe a demonstration chemical experiment of the interaction of lithium and sodium with water. They explain the chemical phenomenon taking place, answer questions posed by the teacher and complete the tasks described on the slide. Write down information about chemical properties in a notebook. |
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| Slide 7. Use of sodium and potassium compounds. The slide is interactive. Work is carried out selectively, in accordance with the remaining time. Working with trivial names of substances. | The picture determines in which area a particular connection is used. By clicking on the picture, a task appears that is completed together, one student at the board. Working with trivial names of substances. |
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| Consolidation | Slide 8. Test work. When completing this task, you must select the correct answer and left-click on it.. | Perform an interactive test. Discussion of test results. |
| Homework |
Sources of information used
Akhmetov M.A., Gara N.N. Chemistry: 9th grade teaching aid, M. Ventana-Graf, 2014
Kuznetsova N.E., Titova I.M., Gara N.N. Chemistry: 9th grade: textbook for students of general education institutions. - 5th ed., revised. - M. Ventana-Graf, 2013
Kuznetsova N.E., Gara N.N. Chemistry: programs: grades 8-11 - 2nd ed., revised. - M. Ventana-Graf, 2012
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Municipal budgetary educational institution "Boarding School No. 1 of secondary (complete) general education" of the urban district of the city of Sterlitamak of the Republic of Bashkortostan Completed by a chemistry teacher of the first qualification category Safikanov Akhat Faizrakhmanovich Safikanov A.F.
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Periodic table of chemical elements by D.I. Mendeleev Groups of elements I III II VIII IV V VI VII II I III VII VI V IV 2 1 3 4 5 6 7 10 F fluorine 9 18.9984 Br Bromine 35 79.904 I Iodine 53 126.904 Cl Chlorine 17 35.453 At Astat 85 210 9 8 Alkali metals Safikanov A.F.
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Groups of elements I III II VIII IV V VI VII II I III VII VI V IV 2 1 3 4 5 6 7 10 9 8 Alkali metals Periodic table of chemical elements by D.I. Mendeleev In the main subgroup: The number of electrons on the outer layer does not change Radius atom increases Electronegativity decreases Reductive properties increase Metallic properties increase Safikanov A.F.
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Periodic table of chemical elements by D.I. Mendeleev Groups of elements I III II VIII IV V VI VII II I III VII VI V IV 2 1 3 4 5 6 7 9 8 10 Lithium / Lithium (Li) Appearance of a simple substance Soft metal silvery - white color. Electronic cofiguration 2s1 EO (according to Pauling) 0.98 Oxidation state 1 Density 0.534 g/cm³ Melting point 453.69 K Boiling point 1613 K Safikanov A.F.
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Periodic table of chemical elements by D.I. Mendeleev Groups of elements I III II VIII IV V VI VII II I III VII VI V IV 2 1 3 4 5 6 7 9 8 10 Sodium/Natrium (Na) Appearance of the simple substance silvery-white soft metal Electronic cofiguration 3s1 EO (according to Pauling) 0.93 Oxidation state 1 Density 0.971 g/cm³ Melting point 370.96 K Boiling point 1156.1 K Safikanov A.F.
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Periodic table of chemical elements by D.I. Mendeleev Groups of elements I III II VIII IV V VI VII II I III VII VI V IV 2 1 3 4 5 6 7 9 8 10 Potassium / Kalium (K) Appearance of the simple substance Silvery-white soft metal Electronic configuration 3d10 4s1 EO (according to Pauling) 0.82 Oxidation state 1 Density 0.856 g/cm³ Melting point 336.8 K Boiling point 1047 K Safikanov A.F.
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Periodic table of chemical elements by D.I. Mendeleev Groups of elements I III II VIII IV V VI VII II I III VII VI V IV 2 1 3 4 5 6 7 9 8 10 Rubidium / Rubidium (Rb) Appearance of the simple substance Silver-white soft metal Electronic configuration 5s1 EO (according to Pauling) 0.82 Oxidation state 1 Density 1.532 g/cm³ Melting point 312.2 K Boiling point 961 K Safikanov A.F.
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Periodic table of chemical elements by D.I. Mendeleev Groups of elements I III II VIII IV V VI VII II I III VII VI V IV 2 1 3 4 5 6 7 9 8 10 Cesium / Caesium (Cs) Appearance of the simple substance very soft viscous silvery -yellow metal similar to gold Electronic configuration 6s1 EO (according to Pauling) 0.79 Oxidation state 1 Density 1.873 g/cm Melting point 301.6 K Boiling point 951.6 K Safikanov A.F.
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Periodic table of chemical elements by D.I. Mendeleev Groups of elements I III II VIII IV V VI VII II I III VII VI V IV 2 1 3 4 5 6 7 9 8 10 Francium (Fr) Appearance of a simple substance radioactive alkali metal Electronic configuration 7s1 EO (according to Pauling) 2.2 Oxidation state 1 Density 1.87 g/cm Melting point 300 K Boiling point 950 K Safikanov A.F.
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Alkali metals Lithium Sodium Potassium Rubidium Cesium Fraicium History of discovery Safikanov A.F.
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Lithium was discovered in 1817 by A. Arfvedson in the mineral petalite. Berzelius proposed to call it lithion, since this alkali was first found in the “kingdom of minerals” (stones); This name is derived from the Greek - stone. Lithium metal was first obtained in 1818 by G. Davy by electrolysis of alkali. In 1855, Bunsen and Matthessen developed an industrial method for producing lithium metal by electrolysis of lithium chloride. Arfvedson Yuhan August (01/12/1792 – 10/28/1841) History of the discovery of lithium Safikanov A.F.
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Sodium (Natrium, from the English and French. Sodium, German Natrium from the Hebrew neter - a seething substance. In 1807, G. Davy, by electrolysis of slightly moistened solid alkalis, obtained the free metal - sodium, calling it sodium (Sodium). In the next year, Gilbert proposed to call the new metal sodium (Natronium); Berzelius shortened the latter name to “sodium” (Humphry Davy (12/17/1778 - 05/29/1829) History of the discovery of sodium A.F. Safikanov).
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Potassium (English Potassium, French Potassium, German Kalium) was discovered in 1807 by G. Davy, who performed the electrolysis of solid, slightly moistened caustic potassium. Davy called the new metal Potassium, but this name did not stick. The godfather of metal turned out to be Gilbert, the famous publisher of the magazine "Annalen de Physik", who proposed the name "potassium"; it was adopted in Germany and Russia. The history of the discovery of potassium by Humphry Davy (12/17/1778 – 05/29/1829) Safikanov A.F.
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A spectroscopic analysis of the mineral lepidolite (lithium aluminum fluorosilicate) revealed two new red lines in the red part of the spectrum. These lines were correctly attributed by R. Bunsen and G. Kirchhoff to a new metal, which was called rubidium (Latin rubidus - red) because of the color of its spectral lines. Bunsen succeeded in obtaining rubidium in metal form in 1863. History of the discovery of rubidium Robert Wilhelm Bunsen (31.03.1811 - 16.08.1899) Gustav Robert Kirchhoff (12.03.1824 - 17.10.1887) Safikanov A.F.
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Cesium (English Cesium, French Cesium, German Caesium) is the first element discovered using spectral analysis. R. Bunsen and G. Kirchhoff discovered spectral lines of the new element: one weak blue and the other bright blue in the violet part of the spectrum. R. Bunsen named the newly discovered metal cesium (Casium) from lat. caesius -- blue, light gray; in ancient times this word denoted the blueness of a clear sky. Pure metallic cesium was obtained electrolytically in 1882. History of the discovery of cesium Robert Wilhelm Bunsen (31.03.1811 - 16.08.1899) Gustav Robert Kirchhoff (12.03.1824 - 17.10.1887) Safikanov A.F.
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This element was predicted by D.I. Mendeleev (as Eka-cesium), and was discovered (by its radioactivity) in 1939 by Marguerite Pere, an employee of the Radium Institute in Paris with serial number Z = 87 and half-life 21 minutes. She gave it the name in 1964 in honor of her homeland - France. . Microscopic amounts of francium-223 and francium-224 can be chemically isolated from uranium and thorium minerals. Other isotopes of francium are produced artificially using nuclear reactions. PEREY (Perey) Margarita (10/19/1909 - 05/13/1975) History of the discovery France Safikanov A.F.
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Spodumenny Photograph Description of the mineral Chemical composition LiAl Color Colorless, red, yellow, green Density 3.1-3.2 g/cm3 Hardness 6.5 Safikanov A.F.
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Halite Photo Description of the mineral Chemical composition NaСl Color Colorless, red, yellow, blue Density 2.2-2.3 g/cm3 Hardness 2.5 Taste Salty Safikanov A.F.
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Silvin Photo Description of the mineral Chemical composition KCl Color Colorless, milky white, dark red, pink Density 1.97-1.99 g/cm3 Hardness 1.5 Taste Acrid Safikanov A.F.
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Carnalite Photo Description of the mineral Chemical composition MgCl2·KCl·6H2O Color Red, yellow, white, colorless Density 1.6 g/cm3 Hardness 1.5 Taste Burning salty Safikanov A.F.
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Chemical properties 2Na + Cl2 = 2NaCl (in an atmosphere of F2 and Cl2 alkaline Me ignite spontaneously) 4Li + O2 = 2Li2O 2Na + O2 = Na2O2 2K + 2O2 = K2O4 Li oxide Na peroxide K 3) 2Na + H2 = 2NaH (when heated to 200- 400oC) 4) 6Li + N2 = 2Li3N (Li - at room T, the rest are alkaline Me - when heated) 5) 2Na + 2H2O = 2NaOH + H2 (Li - calm, Na - energetic, the rest - with an explosion - the released H2 Rb ignites and Cs react not only with liquid H2O, but also with ice. 6) 2Na+ H2SO4 = Na2SO4 + H2 (proceed very violently) 7) 2C2H5OH + 2Na = 2C2H5ONa + H2 Alkali metals with water Safikanov A.F.
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Qualitative determination of alkali metals Li+ Na+ K+ To recognize alkali metal compounds by the color of the flame, the substance under study is introduced into the burner flame at the tip of an iron wire. Li+ - carmine red K+ - violet Cs+ - violet-blue Na+ - yellow Rb + - red Safikanov A.F.
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1) Electrolysis of melts of alkali metal compounds: 2MeCl = 2Me + Cl2 4MeOH = 4Me + 2H2O + O2 2) Reduction of oxides and hydroxides of alkali metals: 2Li2O + Si = 4Li + SiO2 KOH + Na = NaOH + K Preparation of alkali metals The bath consists of steel a casing with fireclay lining, a graphite anode A and an annular iron cathode K, between which a mesh diaphragm is located. The electrolyte is a more fusible mixture of it with 25% NaF and 12% KCl (which allows the process to be carried out at 610–650°C). Metallic sodium is collected in the upper part of the annular cathode space, from where it passes into the collector. As electrolysis progresses, NaCl is added to the bath. Diagram of an electrolyzer for the production of sodium Safikanov A.F.
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Application of alkali metals Lithium For the production of tritium Production of alloys for bearings Reductant in organic synthesis Chemical current sources Pyrotechnics Safikanov A.F.
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Slide captions:
Center for Distance Education of Disabled Children at OSAOU "Belgorod Engineering Youth Boarding School" ALKALI METALS Completed by: Bykova O.S., chemistry teacher
Goal: to repeat the properties of metals, to systematize and deepen knowledge about alkali metals based on their comparative characteristics. To form a concept about the physical and chemical properties of alkali metals.
Structure and properties of atoms
Alkali metals are elements of the main subgroup of group I: lithium Li, sodium Na, potassium K, rubidium Rb, cesium Cs, francium Fr.
At the outer energy level, the atoms of these elements contain one electron each, located at a relatively large distance from the nucleus. They easily give up this electron, so they are very strong reducing agents. In all their compounds, alkali metals exhibit an oxidation state of +1. Their reducing properties increase during the transition from Li to Cs, which is associated with an increase in the radii of their atoms. These are the most typical representatives of metals: their metallic properties are especially pronounced.
Alkali metals - simple substances
Silvery-white soft substances (cut with a knife), with a characteristic shine on the freshly cut surface. All of them are light and fusible, and, as a rule, their density increases from Li to Cs, and the melting point, on the contrary, decreases.
Chemical properties
All alkali metals are extremely active, exhibit reducing properties in all chemical reactions, and give up their only valence electron, turning into a positively charged cation. Simple substances - non-metals, oxides, acids, salts, organic substances - can act as oxidizing agents.
Interaction with non-metals
Alkali metals easily react with oxygen, but each metal shows its own individuality: the oxide forms only lithium: 4Li + O2 = 2Li2O, sodium forms peroxide: 2Na + O2 = Na2O2, potassium, rubidium and cesium form superoxide: K + O2 = KO2.
Interaction with hydrogen, sulfur, phosphorus, carbon, silicon occurs when heated: with hydrogen hydrides are formed: 2Na + H2 = 2NaH, with sulfur - sulfides: 2K + S = K2S, with phosphorus - phosphides: 3K + P = K3P, with silicon – silicides: 4Cs + Si = Cs4Si, with carbon carbides form lithium and sodium: 2Li + 2C = Li2C2
Only lithium reacts easily with nitrogen; the reaction occurs at room temperature with the formation of lithium nitride: 6Li + N2 = 2Li3N. With halogens, all alkali metals form halides: 2Na + Cl2 = 2NaCl.
Interaction with water
All alkali metals react with water, lithium reacts quietly, floating on the surface of water, sodium often ignites, and potassium, rubidium and cesium react explosively:
Alkali metals are capable of reacting with dilute acids to release hydrogen, but the reaction will be ambiguous, since the metal will also react with water, and then the resulting alkali will be neutralized by the acid. When interacting with oxidizing acids, for example, nitric acid, an acid reduction product is formed, although the course of the reaction is also ambiguous. The interaction of alkali metals with acids is almost always accompanied by an explosion, and such reactions are not carried out in practice. Interaction with acids
Alkali metal compounds Alkali metals are not found in free form in nature due to their exceptionally high chemical activity. Some of their natural compounds, in particular sodium and potassium salts, are quite widespread; they are found in many minerals, plants, and natural waters.
Sodium hydroxide NaOH is known in technology under the names caustic soda, caustic soda, caustic soda. The technical name for potassium hydroxide KOH is caustic potash. Both hydroxides, NaOH and KOH, corrode fabrics and paper, which is why they are also called caustic alkalis. Caustic soda is used in large quantities for the purification of petroleum products, in the paper and textile industries, and for the production of soap and fibers. Caustic potassium is more expensive and is used less frequently. Its main area of application is the production of liquid soap.
Alkali metal salts are solid crystalline substances of ionic structure. . Na2СO3 - sodium carbonate, forms crystalline hydrate Na2СO3* 10Н2O, known as crystalline soda, which is used in the production of glass, paper, and soap. You are more familiar with the acid salt in everyday life - sodium bicarbonate NaHCO3, it is used in the food industry (baking soda) and in medicine (baking soda). K2C03 - potassium carbonate, technical name - potash, used in the production of liquid soap. Na2SO4 10H2O - crystalline hydrate of sodium sulfate, technical name - Glauber's salt, used for the production of soda and glass and as a laxative.
NaCl - sodium chloride, or table salt, this salt is well known to you from last year's course. Sodium chloride is the most important raw material in the chemical industry and is widely used in everyday life.
Thank you for your attention!
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Topic: Compounds of alkali metals Test on the topic: Alkali metals. Answers: 1- d 2 - c 3 - b 4 - c 5 - a 6 - d 7 - b 8 - a 9 - b 10 - c. Grading scale: no errors – “5”, 1.2 errors – “4”, 3.4 errors – “3”, more – “2” D/z § 11, ex. 1 (b) p.48. Alkali metals do not include: a) rubidium; c) potassium; b) cesium; d) copper. The electronic formula 1s2 2s2 2p6 3s2 3p6 4s1 corresponds to the element: a) lithium; c) potassium; b) sodium; d) copper. The atomic radius of elements of group I of the main subgroup with increasing nuclear charge: a) changes periodically; c) does not change; b) increases; d) decreases. Alkali metals exhibit very strong: a) oxidizing properties; c) restorative properties; b) amphoteric properties; d) neutral properties. In all their compounds, alkali metals exhibit an oxidation state: a) +1; c) +2; b) +3; d) +4. 6. The physical properties of alkali metals do not include: a) silvery-white; c) good electrical conductors; b) soft and light; d) refractory. 7. When elements of group I of the main subgroup interact with water, the following is formed: a) acid; c) oxide and hydrogen is released; b) alkali and hydrogen is released; d) salt. 8. When oxygen interacts with alkali metals, an oxide is formed only with: a) lithium; c) potassium; b) sodium; d) rubidium. 9. Alkali metals do not interact with: a) non-metals; c) water; b) acid solutions; d) concentrated acids. 10. Sodium and potassium are stored in kerosene or mineral oil because they: a) have a pungent odor; c) are easily oxidized in air; b) very light; d) strong oxidizing agents.
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2. Alkali metal hydroxides a) physical properties: b) chemical properties: Instructions Pour sodium hydroxide into a clean test tube, add a few drops of phenolphthalein. What are you observing? Add hydrochloric acid solution to the same test tube. What are you observing? Write down the reaction equation. Pour sodium hydroxide into a clean test tube and add copper sulfate solution. What are you observing? Write down the reaction equation. Carefully add sodium hydroxide to the test tube containing zinc hydroxide. What are you observing? Write down the reaction equation. Draw a conclusion about the chemical properties of alkali metal hydroxides.
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2. Alkali metal hydroxides c) application: Sodium hydroxide – NaOH – caustic soda, caustic soda, caustic. Potassium hydroxide - KOH - caustic potash. NaOH and KOH are caustic alkalis that corrode fabrics and paper
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3. Alkali metal salts baking soda potash table salt Glauber's salt crystalline soda Salt formula name application
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4. The importance of alkali metal compounds in the life of organisms Sodium and potassium ions play an important biological role: Na+ is the main extracellular ion, found in the blood and lymph, and K+ is the main intracellular ion. The ratio of the concentration of these ions regulates blood pressure in a living organism and ensures the movement of salt solutions from the roots to the leaves of plants. Potassium ions - support the functioning of the heart muscle, help with rheumatism, and improve intestinal function. Potassium compounds – eliminate swelling.
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An adult should consume 3.5 g of potassium ions per day with food. Task. 100g of dried apricots contains 2.034g of potassium. How many grams of dried apricots should you eat to get your daily requirement of potassium? Lesson summary: What physical and chemical properties are characteristic of oxides and hydroxides of alkali metals. Where are alkali metal hydroxides and salts used? Thank you for your work.
"Iron metal" - Fe. Chemical properties. Iron. Iron or sulfur pyrite (pyrite) FeS2. Physical properties. Chemical properties of iron. Pyrite. Chalcopyrite with quartz inclusions Primorsky Krai. Red iron ore hematite Fe2O3. Fe0 - 2e = Fe+2 Cl02+2e=2Cl-1. Iron is a relatively soft, malleable, silver-gray metal.
“Lesson Silicon” - Which chemical element is the most important in living and non-living nature? The substance is gray. The structure is tetrahedral. Old manuscript. The substance is soft. Team evaluation, everyone gets points. Work in pairs, mutual checking - no errors (5), two errors (4), etc. Which chamomile petals can be friends? Silicon oxide is an acidic oxide.
“Nitrogen oxide” - Nitric oxide (V). +3 +5 2NO2 + H2O = HNO2 + HNO3. Several nitrogen oxides are known. +1 +2 +3 +4 +5. N2O. The oxidation state does not always coincide with the valence. Against all the rules. Like nitrogen(III) oxide, it has no practical significance. Nitrogen oxides. Non-salt-forming: N2O NO. 2NO2 === N2O4. NO. Nitrogen is capable of exhibiting several oxidation states from -3 to +5.
“Obtaining radioactive isotopes” - Industry. Radioactive isotopes in medicine. Elements that do not exist in nature. Radioactive isotopes in industry. Iodine is intensively deposited in the thyroid gland, especially in Graves' disease. A method for monitoring piston ring wear in internal combustion engines. Radioactive isotopes are widely used in science, medicine and technology.
“Oxygen compounds” - Hydrogen compounds N. N – 1772, English. Likewise for Li2NH (imide), Li3N (nitride). Acid-base properties in water. 9. Group V of the periodic table. 13. 4. Receipt. 12. 8. 3. Properties. Opening elements. 14.11.
“Lesson on Phosphorus Compounds” - Educational program of Cyril and Methodius (section Non-metals. Reagents - red phosphorus. Interactive board. Stage 2. Operational execution. Oxygen compounds of phosphorus. 1. Students’ work with the educational programs Cyril and Methodius and Open Chemistry (2.6). Formation of skills in working with educational computer programs.
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