React with an ammonia solution of silver oxide 1. Silver mirror reaction: dissolve silver oxide in ammonia water

My light, mirror, tell me and tell me the whole truth... how did ammonia solution give you the remarkable ability to reflect light and show the face looking at you? In fact, there is no secret. known since the end of the 19th century thanks to the work of German chemists.

- the metal is quite durable, does not rust and does not dissolve in water. You can silver water, but no one will say that it is a silver solution. Water will remain water, even if it is treated and disinfected. They learned to purify water this way in ancient times and still use this method in filters.

But silver salts and oxides readily enter into chemical reactions and dissolve in liquids, resulting in the formation of new substances that are in demand both in technology and in everyday life.

The formula is simple - Ag 2 O. Two silver atoms and an oxygen atom form silver oxide, which is sensitive to light. However, other compounds have found greater use in photography, but the oxide has shown affinity for ammonia reagents. In particular, ammonia, which our grandmothers used to clean products when they darkened.

Ammonia is a compound of nitrogen and hydrogen (NH 3). Nitrogen makes up 78% of the earth's atmosphere. It is everywhere, as one of the most abundant elements on Earth. The ammonia-water solution is so widely used that it has received several names: ammonia water, ammonium hydroxide, ammonium hydroxide, ammonia hydroxide. It's easy to get confused in such a series of synonyms. If you dilute ammonia water to a weak 10% solution, you get ammonia.

When chemists dissolved the oxide in ammonia water, a new substance appeared to the world - a complex compound of silver diamine hydroxide with very attractive properties.

The process is described by the chemical formula: Ag 2 O + 4NH 4 OH = 2OH + 3H2O.

Process and formula of the chemical reaction of ammonia water and silver oxide

In chemistry, this substance is also known as Tollens' reagent and is named after the German chemist Bernhard Tollens, who described the reaction in 1881.

If only the laboratory didn't explode

It quickly became clear that the ammonia solution of silver oxide, although not stable, is capable of forming explosive compounds during storage, so it is recommended to destroy the residues at the end of the experiments. But there is also a positive side: in addition to metal, the composition contains nitrogen and oxygen, which, during decomposition, makes it possible to release silver nitrate, familiar to us as medical lapis. It’s not so popular now, but it was once used to cauterize and disinfect wounds. Where there is a danger of explosion, there are means of treatment.

And yet, the ammonia solution of silver oxide gained fame thanks to other, no less important phenomena: from explosives and silvering of mirrors to extensive research in anatomy and organic chemistry.

When acetylene is passed through an ammonia solution of silver oxide, the output is very dangerous silver acetylide. It is capable of exploding when heated and mechanically, even from a smoldering splinter. When conducting experiments, care should be taken to isolate acetylenide in small quantities. How to clean laboratory glassware is described in detail in the safety instructions.
If you pour silver nitrate into a round-bottomed flask, add ammonia solution and glucose and heat it in a water bath, the metal part will settle on the walls and bottom, creating a reflection effect. The process was called the “silver mirror reaction.” Used in industry for the production of Christmas tree balls, thermoses and mirrors. Sweet glucose helps bring the product to a mirror shine. But fructose does not have this property, although it is sweeter.
Tollens' reagent is used in pathological anatomy. There is a special technique (Fontana-Masson method) for staining tissues, with which, upon autopsy, melanin, argentaffin cells and lipofuscin (an aging pigment involved in intercellular metabolism) are determined in tissues.
Used in organic chemistry for the analysis and detection of aldehydes, reducing sugars, hydroxycarboxylic acids, polyhydroxyphenols, primary ketoalcohols, aminophenols, α-diketones, alkyl- and arylhydroxylamines, alkyl- and arylhydrazines. This is an important and necessary reagent. He contributed a lot to organic research.

As you can see, silver is not only jewelry, coins and photo reagents. Solutions of its oxides and salts are in demand in a variety of areas of human activity.

The name “silver” comes from the Assyrian “sartsu” (white metal). The word "argentum" is probably related to the Greek "argos" - "white, shiny".

Being in nature. Silver is much less common in nature than copper. In the lithosphere, silver accounts for only 10 -5% (by mass).

Native silver is very rare; most silver is obtained from its compounds. The most important silver ore is silver luster, or argentite Ag 2 S. Silver is present as an impurity in almost all copper and lead ores.

Receipt. Almost 80% of silver is obtained as a by-product with other metals during the processing of their ores. Silver is separated from impurities by electrolysis.

Properties. Pure silver is a very soft, white, malleable metal characterized by exceptionally high electrical and thermal conductivity.

Silver is a low-active metal, which is classified as a so-called noble metal. In air it does not oxidize either at room temperature or when heated. The observed blackening of silver items is the result of the formation of black silver sulfide Ag 2 S on the surface under the influence of hydrogen sulfide in the air:

Blackening of silver also occurs when objects made from it come into contact with food products containing sulfur compounds.

Silver is resistant to dilute sulfuric and hydrochloric acids, but is soluble in nitric and concentrated sulfuric acids:

Application. Silver is used as a component of alloys for jewelry, coins, medals, solders, tableware and laboratory utensils, for silvering parts of apparatus in the food industry and mirrors, as well as for the manufacture of parts for electric vacuum devices, electrical contacts, electrodes, for water treatment and as a catalyst in organic synthesis.

Let us recall that silver ions, even in negligible concentrations, are characterized by a strongly pronounced bactericidal effect. In addition to water treatment, this is used in medicine: colloidal silver solutions (protargol, collargol, etc.) are used to disinfect mucous membranes.

Silver compounds. Silver oxide (I) Ag 2 O is a dark brown powder, exhibits basic properties, is poorly soluble in water, but gives the solution a slightly alkaline reaction.

This oxide is obtained by carrying out a reaction whose equation is

The silver (I) hydroxide formed in the reaction, a strong but unstable base, decomposes into oxide and water. Silver(I) oxide can be produced by treating silver with ozone.

You know an ammonia solution of silver (I) oxide as a reagent: 1) for aldehydes - as a result of the reaction, a “silver mirror” is formed; 2) to alkynes with a triple bond at the first carbon atom - as a result of the reaction, insoluble compounds are formed.

An ammonia solution of silver (I) oxide is a complex compound of diammine silver (I) hydroxide OH.

Silver nitrate AgNO 3, also called lapis, is used as an astringent bactericidal agent in the production of photographic materials and in electroplating.

Silver fluoride AgF is a yellow powder, the only halide of this metal that is soluble in water. Obtained by the action of hydrofluoric acid on silver (I) oxide. It is used as a component of phosphors and a fluorinating agent in the synthesis of fluorocarbons.

Silver chloride AgCl is a white solid that forms as a white cheesy precipitate when chloride ions are detected that react with silver ions. When exposed to light, it decomposes into silver and chlorine. Used as a photographic material, but significantly less than silver bromide.

Silver bromide AgBr is a light yellow crystalline substance, formed by the reaction between silver nitrate and potassium bromide. Previously, it was widely used in the manufacture of photographic paper, film and photographic film.

Silver chromate Ag 2 CrO 4 and silver dichromate Ag 2 Cr 2 O 7 are dark red crystalline substances that are used as dyes in the manufacture of ceramics.

Silver acetate CH 3 COOAg is used in electroplating for silvering metals.

1. Pentin-1 reacts with an ammonia solution of silver oxide (a precipitate forms):

HCºС-CH 2 -CH 2 -CH 3 + OH → AgСºС-CH 2 -CH 2 -CH 3 + 2NH 3 +H 2 O

2. Cyclopentene decolorizes bromine water:

3. Cyclopentane does not react with either bromine water or an ammonia solution of silver oxide.

Example 3. Five numbered test tubes contain hexene, formic acid methyl ester, ethanol, acetic acid, and an aqueous solution of phenol.

It has been established that when metallic sodium acts on substances, gas is released from test tubes 2, 4, 5. Substances from test tubes 3, 5 react with bromine water; with an ammonia solution of silver oxide - substances from test tubes 1 and 4. Substances from test tubes 1, 4, 5 react with an aqueous solution of sodium hydroxide.

Determine the contents of the numbered tubes.

Solution. For recognition, let’s draw up Table 2 and immediately make a reservation that the conditions of this problem do not take into account the possibility of a number of interactions, for example, methyl formate with bromine water, phenol with a solution of diammine silver hydroxide. The - sign denotes the absence of interaction, and the + sign denotes the ongoing chemical reaction.

Table 2

Interactions of analytes with proposed reagents

Example 4. Six numbered test tubes contain solutions: isopropyl alcohol, sodium bicarbonate, acetic acid, aniline hydrochloride, glycerin, protein. How to determine which test tube contains each substance?

Solution. .

When bromine water is added to solutions in numbered test tubes, a precipitate is formed in the test tube with aniline hydrochloride as a result of its interaction with bromine water. The identified solution of aniline hydrochloride is applied to the remaining five solutions. In a test tube with a solution of sodium bicarbonate, carbon dioxide is released. The established solution of sodium bicarbonate acts on the other four solutions. Carbon dioxide is released in a test tube containing acetic acid. The remaining three solutions are treated with a solution of copper (II) sulfate, which causes the appearance of a precipitate as a result of protein denaturation. To identify glycerol, copper (II) hydroxide is prepared from solutions of copper (II) sulfate and sodium hydroxide. Copper(II) hydroxide is added to one of the remaining two solutions. When copper(II) hydroxide dissolves to form a clear, bright blue solution of copper glycerate, glycerol is identified. The remaining solution is an isopropyl alcohol solution.

Example 5. Seven numbered test tubes contain solutions of the following organic compounds: aminoacetic acid, phenol, isopropyl alcohol, glycerin, trichloroacetic acid, aniline hydrochloride, glucose. Using only solutions of the following inorganic substances as reagents: 2% copper (II) sulfate solution, 5% iron (III) chloride solution, 10% sodium hydroxide solution and 5% sodium carbonate solution, determine the organic substances contained in each test tube.

Solution. We immediately warn you that here we offer a verbal explanation of the identification of substances .

When iron(III) chloride solution is added to solutions taken from the numbered test tubes, a red color is formed with aminoacetic acid and a violet color with phenol. When adding a solution of sodium carbonate to samples of solutions taken from the remaining five test tubes, carbon dioxide is released in the case of trichloroacetic acid and aniline hydrochloride; there is no reaction with other substances. Aniline hydrochloride can be distinguished from trichloroacetic acid by adding sodium hydroxide to them. In this case, an emulsion of aniline in water is formed in a test tube with aniline hydrochloride; no visible changes are observed in a test tube with trichloroacetic acid. The determination of isopropyl alcohol, glycerol and glucose is carried out as follows. In a separate test tube, by mixing 4 drops of a 2% solution of copper (II) sulfate and 3 ml of a 10% solution of sodium hydroxide, a blue precipitate of copper (II) hydroxide is obtained, which is divided into three parts.

A few drops of isopropyl alcohol, glycerin and glucose are added separately to each part. In a test tube with the addition of isopropyl alcohol, no changes are observed; in test tubes with the addition of glycerin and glucose, the precipitate dissolves with the formation of complex compounds of intense blue color. The resulting complex compounds can be distinguished by heating the upper part of the solutions in test tubes on a burner or alcohol lamp until they begin to boil. In this case, no color change will be observed in the test tube with glycerol, and in the upper part of the glucose solution a yellow precipitate of copper (I) hydroxide appears, turning into a red precipitate of copper (I) oxide; the lower part of the liquid, which was not heated, remains blue.

Example 6. Six test tubes contain aqueous solutions of glycerin, glucose, formalin, phenol, acetic and formic acid. Using the reagents and equipment on the table, identify the substances in the test tubes. Describe the process of determination. Write the reaction equations on the basis of which the substances are determined.

Reagents: CuSO 4 5%, NaOH 5%, NaHCO 3 10%, bromine water.

Equipment: rack with test tubes, pipettes, water bath or hotplate.

Solution

1. Determination of acids.

When carboxylic acids interact with a solution of sodium bicarbonate, carbon dioxide is released:

HCOOH + NaHCO 3 → HCOONa + CO 2 + H 2 O;

CH 3 COOH + NaHCO 3 → CH 3 COONa + CO 2 + H 2 O.

Acids can be distinguished by reaction with bromine water. Formic acid discolors bromine water

HCOOH + Br 2 = 2HBr + CO 2.

Bromine does not react with acetic acid in an aqueous solution.

2. Determination of phenol.

When glycerin, glucose, formalin and phenol interact with bromine water, only in one case is the solution clouded and a white precipitate of 2,4,6-tribromophenol forms.

Glycerin, glucose and formalin are oxidized by bromine water, and discoloration of the solution is observed. Glycerol under these conditions can be oxidized to glyceraldehyde or 1,2-dihydroxyacetone

Further oxidation of glyceraldehyde leads to glyceric acid.

HCHO + 2Br 2 + H 2 O → CO 2 + 4HBr.

Reaction with freshly prepared copper(II) hydroxide precipitate allows one to distinguish between glycerol, glucose and formaldehyde.

When glycerin is added to copper(II) hydroxide, the blue cheesy precipitate dissolves and a bright blue solution of complex copper glycerate is formed. When heated, the color of the solution does not change.

Adding glucose to copper(II) hydroxide also produces a bright blue solution of the complex

However, when heated, the complex is destroyed and the aldehyde group is oxidized, resulting in a red precipitate of copper (I) oxide.

Formalin reacts with copper(II) hydroxide only when heated to form an orange precipitate of copper(I) oxide.

HCHO + 4Cu(OH) 2 → 2Cu 2 O↓ + CO 2 + 5H 2 O.

All described interactions can be presented in Table 3 for ease of determination.

Table 3

Determination results

Literature

1. Traven V. F. Organic chemistry: Textbook for universities: In 2 volumes / V. F. Traven. – M.: ICC “Akademkniga”, 2006.

2. Smolina T. A. et al. Practical work in organic chemistry: Small workshop. Textbook for universities. / T. A. Smolina, N. V. Vasilyeva, N. B. Kupletskaya. – M.: Education, 1986.

3. Kucherenko N. E. et al. Biochemistry: Workshop /N. E. Kucherenko, Yu. D. Babenyuk, A. N. Vasiliev and others - K.: High School, Kyiv Publishing House. Univ., 1988.

4. Shapiro D.K. Workshop on biological chemistry. – Mn: Higher School, 1976.

5. V. K. Nikolaenko. Solving problems of increased complexity in general and inorganic chemistry: A manual for teachers, Ed. G.V. Lisichkina - K.: Rad.shk., 1990.

6. S. S. Churanov. Chemistry Olympiads at school: A manual for teachers. – M.: Education, 1962.

7. Moscow city chemical Olympiads: Methodological recommendations. Compiled by V.V. Sorokin, R.P. Surovtseva - M,: 1988

8. Modern chemistry in the problems of international olympiads. V. V. Sorokin, I. V. Svitanko, Yu. N. Sychev, S. S. Churanov - M.: Chemistry, 1993

9. E. A. Shishkin. Teaching students to solve quality problems in chemistry. – Kirov, 1990.

10. Chemistry Olympiads in problems and solutions. Parts 1 and 2. Compiled by Kebets A.P., Sviridov A.V., Galafeev V.A., Kebets P.A. - Kostroma: KGSHA Publishing House, 2000.

11. S. N. Perchatkin, A. A. Zaitsev, M. V. Dorofeev. Chemical Olympiads in Moscow. – M.: MIKPRO Publishing House, 2001.

12. Chemistry 10-11: Collection of problems with solutions and answers / V.V. Sorokin, I.V. Svitanko, Yu.N. Sychev, S.S. Churanov. – M.: AST Publishing House: Publishing House LLC ASTREL", 2001.

This problem was proposed to 11th grade students at the practical round of the III (regional) stage of the All-Russian Olympiad for Schoolchildren in Chemistry in the 2009-2010 academic year.

Interaction with an ammonia solution of silver (I) oxide – “silver mirror reaction”.

Silver (I) oxide is formed by the reaction of silver (I) nitrate with NH 4 OH.

Metallic silver is deposited on the walls of the test tube in the form of a thin layer, forming a mirror surface.

Interaction with copper(II) hydroxide.

For the reaction, freshly prepared Cu(OH) 2 with alkali is used - the appearance of a brick-red precipitate indicates the reduction of divalent copper to monovalent copper due to the oxidation of the aldehyde group.

Polymerization reactions (characteristic of lower aldehydes).

Linear polymerization.

When a formaldehyde solution evaporates or stands for a long time, a polymer is formed - paraformaldehyde: n(H 2 C=O) + nH 2 O → n (paraformaldehyde, paraform)

Polymerization of anhydrous formaldehyde in the presence of a catalyst – iron pentacarbonyl Fe(CO) 5 – leads to the formation of a high molecular weight compound with n=1000 – polyformaldehyde.

Cyclic polymerization (trimerization, tetrametrization).

Cyclic polymer

Polycondensation reactions.

Polycondensation reactions are processes of the formation of high molecular weight substances, during which the combination of the original monomers of molecules is accompanied by the release of low molecular weight products such as H2O, HCl, NH3, etc.

In an acidic or alkaline environment, when heated, formaldehyde forms high molecular weight products with phenol - phenol-formaldehyde resins of various structures. First, in the presence of a catalyst, interaction occurs between a formaldehyde molecule and a phenol molecule to form phenol alcohol. When heated, phenol alcohols condense to form phenol-formaldehyde polymers.

Phenol-formaldehyde resins are used to produce plastics.

Methods of obtaining:

1. oxidation of primary alcohols:

a) catalytic (cat. Cu, t);

b) under the influence of oxidizing agents (K 2 Cr 2 O 7, KMnO 4 in an acidic environment).

2. catalytic dehydrogenation of primary alcohols (cat. Cu, 300 o C);

3. hydrolysis of dihaloalkanes containing 2 halogen atoms at the first carbon atom;

4. Formaldehyde can be obtained from the catalytic oxidation of methane:

CH 4 + O 2 → H 2 C=O + H 2 O (cat. Mn 2+ or Cu 2+, 500 o C)

5. Acetaldehyde is obtained by Kucherov’s reaction from acetylene and water in the presence of mercury (II) salts.

Practical lesson No. 5.

Topic: “Carboxylic acids.”

Type of lesson: combined (learning new material, repeating and systematizing what has been learned).

Type of lesson: practical lesson.

Time: 270 minutes.

Venue: classroom for practical work in chemistry (No. 222).

Lesson objectives:

Educational:

1. seek an understanding of the mutual relationship between the structure of substances and their chemical properties;

2. consolidate knowledge about the chemical properties of carboxylic acids;

3. learn to compose reaction equations characterizing the chemical properties of these homologous series;

4. consolidate knowledge about qualitative reactions to functional groups of organic substances and the ability to confirm these properties by recording reaction equations.

Educational– to develop in students the ability to think logically, to see cause-and-effect relationships, and the qualities necessary in the work of a pharmacist.

After the lesson, the student should know:

1. classification, isomerism, nomenclature of carboxylic acids;

2. basic chemical properties and methods for producing carboxylic acids;

3. qualitative reactions to carboxylic acids.

After the lesson, the student should be able to:

1. write equations of chemical reactions characterizing the properties of carboxylic acids.

Lesson plan and structure

carbon dioxide

1. aldehyde

Ammonia solution of silver oxide

Oxidative

2. restorative

3. amphoteric

4. acidic

Lipoic acid

2.hydroxylipoic acid

3. nitrolipoic acid

4. aminolipoic acid

A-2-hydroxybutanedioic acid, B-2-oxobutanedioic acid

2. A-2-oxobutanedioic acid, B-2-hydroxybutanedioic acid

3. A – dihydroxybutanedioic acid, B – 2-oxobutanedioic acid

4. A - 2-hydroxybutanedioic acid, B - butanedioic acid

21. The final product of the reduction of 5-nitrofurfural is..

1. 5-hydroxyfurfural

Aminofurfural

3. 5-methoxyfurfural

4. 5-methylaminofurfural

22. Malic acid is oxidized with the participation of NAD + in

Oxaloacetic acid

2. acetic acid

3. succinic acid

4. oxalic acid

23. A substance with the composition C 4 H 8 O, when interacting with a freshly prepared solution of Cu(OH) 2, produces isobutyric acid, is called...

Methylpropanal

2) Butanone

3) 2-methylpropanol-1

Butanal

24. Oxidative NAD + -dependent deamination of amino acids proceeds through the stage of formation...

5.hydroxy acids

Imino acids

7. unsaturated acids

8. polyhydric acids

25. The formation of cystine from cysteine refers to...

1. addition reactions

2. substitution reactions

3. oxidation reactions

Nucleophilic addition reactions

26. During oxidative NAD + dependent deamination of 2-aminopropanoic acid

is formed...

1. 2 – hydroxypropanoic acid

2. 2 – oxopropanoic acid

3. 2 – methylpropanoic acid

4. 2 - methoxypropanoic acid

27. Aldehydes are reduced to...

1. carboxylic acids

Primary alcohols

3. secondary alcohols

4. epoxides

28. When ketones are reduced,…

1. primary alcohols

2. polyhydric alcohols

Secondary alcohols

4. carboxylic acids

29.Epoxides are formed by the oxidation of bonds with oxygen:

4. C = C

30. A qualitative reaction to unsaturated hydrocarbons is their oxidation with potassium permanganate. This creates:

1. carboxylic acids

2. aldehydes

Diols

4. aromatic compounds

31. Oxidation of ethyl alcohol in the body occurs with the participation of a coenzyme:

1. OVER +

3.hydroquinone

4. cyanocobalamin

31. When ethyl alcohol oxidizes in the body, the following is formed:

1. hemoglobin

Acetaldehyde

3. amino acids

4. carbohydrates

32. NAD + and NADH contain the nucleic base____:

Adenine

4. cytosine

33. The structure of riboflavin includes a heterocycle ______...

1.porphyrin

3. quinoline

Isoalloxazine

34. The oxidation of 4-methylpyridine produces...

Nicotinic acid

2. isonicotinic acid

3. stearic acid

4. butyric acid

35. Imino acid is an intermediate product in....

1. during the oxidation of aromatic compounds with oxygen

During oxidative deamination of amino acids

3. during the reduction of disulfides

4. during the oxidation of thioalcohols

36. Lactose belongs to the reducing bioses and is oxidized to...

1. Lactonic acid

Lactona

3. lactobionic acid

4. lactide

37. When nitrofurfural is reduced,… is formed.

1. furatsilin

2. furallidone

Aminofurfural

4. amidopyrine

38. During oxidative deamination of α-alanine,...

Pyruvic acid

2. oxalic acid

3. Lactic acid

4. oxaloacetic acid

39. When glucose is reduced,...

Sorbitol

2. glucuronic acid

4. gluconic acids

40. Tyrosine is formed during the hydroxylation reaction...

Phenylalanine amino acids

2. Amino acid tryptophan

3. heterocyclic pyridine compound

4. adrenaline hormone

41. Nitro compounds are transformed in the body by reduction to

1. nitrites

Aminov

3. hydroxylamines

4. oximes

42. Amines can be prepared by the reaction...

1.oxidation of nitro compounds

Reduction of nitro compounds

3. polymerization of nitro compounds

4. dehydration of nitro compounds

43. Disulfides are obtained as a result of the oxidation reaction...

Sulfonic acids

2. thioalcohols

3. amino alcohols

4. sulfates

44. In the body, lactic acid under the influence of NAD + ……. to pyruvic acid:

Oxidizes

2. restored

4.hydrolyses

45. In the body, pyruvic acid under the influence of NADH……. to lactic acid:

1. oxidizes

Recovering

4.hydrolyses

46. Isoallaxosin in the composition of riboflavin is restored in the body to:

1. dihydroxyisoallaxosine

Dihydroisoallaxosine

3. allaxosin

4. dihydroxyallaxosine

47. Coenzyme NAD + is...

Oxidized form

2. restored form

3. tautameric form

4. mesomeric form

48. NADH is the _________ form of coenzyme

1. oxidized

Restored

3. tautameric

4. mesomeric

49. The coenzyme NAD + contains carbohydrate….

1. fructofuranose

2. glucofuranose

3.glucopyranose

Ribofuranose

50. How many phosphoric acid residues are included in the coenzyme nicotinamide adenine dinucleotide.

51. Nicotinamide, which is part of NAD +, NADH, NADP +, NADPH, is called a vitamin:

52. In vivo, 2-oxoglutaric acid is reduced to glutamic acid with the participation of the coenzyme ...

NADH

53. In the body, ethyl alcohol is oxidized to acetaldehyde with the participation of a coenzyme...

1. OVER +

54. Calcium gluconate used in medicine is a salt of D - gluconic acid. D – gluconic acid is formed by the oxidation of glucose with bromine water. Which characteristic group is oxidized by bromine to form this acid?

1. alcohol

Aldehydic

3. hydroxyl

4. sulfhydryl

55. Glucose oxidation reactions are used to detect it in biological fluids (urine, blood). It is most easily oxidized in the glucose molecule...

1. alcohol groups

Hydrocarbon skeleton

3. carbonyl group

4. hydrogen atoms

54. Nitroso compounds are an intermediate product…..

1. reduction of amines

2. oxidation of amines

Nicotine

2. paraffin

3. mothballs

4. guanine

56. Which fragment of the coenzyme NAD + and NADH does the “+” sign refer to?

1. phosphoric acid residues

1. nicotinamide

Ribose

4. adenine

57. Hydroquinones contain...

1. two aldehyde groups

2. two carboxyl groups

Two hydroxyl groups

4. two amino groups

58. FAD is the active form…..

1. Coenzyme Q

2. vitamin K 2

3. vitamin B 2

4. adrenaline

59. FAD in the process of oxidation in the body….

1. accepts two protons and two electrons (+ 2H +, +2e)

2. donates two protons and two electrons (-2H +, - 2e)

3.either gives or receives depending on the substrate

4. does not give or receive protons

60. Select the aromatic heterocyclic system that is part of the coenzyme FADN 2.

Isoallaxosin

2. nicotinamide

3. dihydroisoallaxosine

4. dihydroquinone

61. Select the nucleic base that is part of FAD.

Adenine

4. cytosine

62. Select the product that is formed during the oxidation of succinate (a salt of succinic acid) with the participation of NAD +.

1. malate (malic acid salt)

2. pyruvate (salt of pyruvic acid)

Oxoacids

4. carboxylic acids

68. Select the product that is formed during the oxidative deamination of glutamic acid.

1. 2-oxoglutaric acid

Oxoglutaric acid

3. citric acid

4. malic acid

69. Flavin adenine dinucleotide (FAD +) exhibits... in redox reactions...

1. restorative properties

2. amphoteric properties

Oxidative properties.

4. acid properties

70. Coenzyme Q is a derivative of….

1. naphthoquinone

Benzoquinone

3. quinoline

4. mothballs

71. Menaquinone (vitamin K 2) is a derivative of….

Naphthoquinone

2. benzoquinone

3. quinoline

4. mothballs

72. What is the name of the intermediate product of the oxidation of double bonds:

1. hydroxide

Epoxide

73. Choose the correct name for the final product of the following transformation:

1. hydroxylamine

Amine

3. nitrosyl

4. nitrosamine

74. Choose the correct name of the final reaction product:

Lipoic acid

2. dehydrolipoic acid

3. citric acid

4. fatty acid

75. Choose the correct name for the proposed connection:

1. flavin adenine dinucleotide

2. isoallaxosin

Riboflavin

4. flavin adenine mononucleotide

76. Choose the correct continuation of the definition: an oxidizing agent in organic chemistry is a compound that...

3. gives away only electrons

Only accepts electrons

77. Choose the correct continuation of the definition: a reducing agent in organic chemistry is a compound that...

1. donates two protons and two electrons

2. accepts two protons and two electrons

Gives away only electrons

4. accepts only electrons

78. What type of reaction can be attributed to the transformation of ethyl alcohol into acetaldehyde with the participation of NAD +.

1. neutralization

2. dehydration

Oxidation

4. additions - detachments

79. What acid is formed during the oxidation of ethylbenzene:

1. toluidine

2. benzoin + formic

3. salicylic

4. benzoin + vinegar

80. To what products are ubiquinones reduced in the body? Choose the correct answer.

Hydroquinones

2.menoquinones

3. phylloquinones

4. naphthoquinones

81. Indicate the reaction by which the most active hydroxyl radical is formed in the body

1. H 2 O 2 + Fe 2+

2. O 2 . +O 2 . + 4 N +

82. Which radical is called a superoxide anion radical?

2. O 2 .

83. Indicate the reaction by which superoxide anion radical is formed in the body

1. O 2 + e

84. Indicate the reaction by which dismutation is carried out

superoxide anion radicals

3. O 2 . + O 2 . + 4 N +

4.RO 2. +RO 2.

85. Indicate the reaction by which hydrogen peroxide is destroyed in the body without the formation of free radicals

1. H 2 O 2 → 2 OH.

3. O 2 . + O 2 . + 4 N +

4.RO 2. +RO 2.

carbon dioxide

17. The oxidizing agent in the reaction of a silver mirror is _____...

1. aldehyde

2. ammonia solution of silver nitrate

ammonia solution of silver oxide

4. ammonia solution of silver chloride

18. In the silver mirror reaction, aldehydes exhibit _________ properties.

Oxidative

2. restorative

3. amphoteric

4. acidic

19. Dihydrolipoic acid is oxidized to ____….

Lipoic acid

2.hydroxylipoic acid

3. nitrolipoic acid

4. aminolipoic acid

20. Select reaction products A and B from the given answers