“Use of fats” - Perfumery. Animal food. Fats. Why sweet is better than fatty? Soap. How much and what kind of fats does a person need? Chocolate. Use of fats. Candles. Glycerol. Propolis. Dye.
“Properties and uses of fats” - Margarine. 600 allocated various types fat Practical application in life. A mixture of esters. Charles Wurtz. Determination of fat unsaturation. Fat synthesis. Fats. Discoloration of bromine water. Alkalis. Cocoa beans. Mixture. Preparation of oil paints. Fat hydrolysis reaction equation. Inedible fat.
"Essential oils" - Phenols. Greek warriors treated wounds with ointments made from myrrh. Pinen. Ethers. Oxygen is the main element of essential oil. Stress Bath. Ketones relieve congestion and accelerate mucus circulation. The aroma is cold, fresh, bitter. What is aromatherapy? The healing properties of mint were used 3000 years ago in Ancient Egypt.
"Edible fats" - Edible fats. Characterize one sample of vegetable oil. Orientation. Questions prepared in advance. Solve the crossword puzzle. Mustard oil. Transfer greatest number names of edible fats. About the rules for purchasing and storing oils. Authenticity of the goods. The content of the work. Chess. Stages of the commodity all-around competition.
“Chemistry Fats grade 10” - Fats. Conclusion: Strong acids displace weak acids from salt solutions. Sodium stearate. Properties of carb. to-t, similar to mineral ones, using acetic acid as an example. Esters. Laboratory experiment No. 1 “The effect of strong acids on soap” L. Alkaline hydrolysis of fats. Laboratory experiment No. 2 “The effect of soap in hard water.”
"Esters and fats" - Acetic acid. To shift the equilibrium to the right, it is necessary to remove water or ether. Fats are widely distributed in nature and, based on their origin, are divided into animal and vegetable. Esters are very common in nature. Esters with a pleasant odor are used in perfumery and the food industry.
There are a total of 13 presentations in the topic
Answer from Elena Kazakova[guru]
They are hydrophobic.
Hydrophobic molecules surrounded by water tend to move closer together because the structure of water, stabilized by hydrogen bonds, is least disrupted. In this case, the total surface area wetted by water is the smallest.
Answer from Yustas[guru]
Because fats are mostly hydrophobic. Because hydrophobes have small parts of molecules that interact with water, then accordingly they partially dissolve, but not completely, and the poor interaction is due to the small angle of interaction between water and fat molecules)
Answer from Aka Diesel[guru]
Because it doesn't matter!
Answer from Krosh[newbie]
Fats are lighter than water!!!
Answer from Serserkov[guru]
Water is a polar solvent; it dissolves substances with a polar molecular structure. Fats are non-polar. hence their hydrophobicity. In fact, they dissolve, but very poorly.
Answer from Elena Yashina[active]
The water of man, the fat of God. “Give this to God” (Pentateuch of Moses, Leviticus, it seems). Water is a symbol of repentance, John the Baptist, the best of men. Oil, oil is a symbol of God. The interaction of God and man, Under the influence of the sun, fire (the Word of God is fire), water disintegrates, rises to heaven, turns into clouds, again into water and falls to the ground either in the form of fertile rain, watering the dry earth, or irrigating the fertile earth again and again , or in the form of more formidable precipitation, punishing the wicked when necessary. Water above, in the sky, and water below on earth, in the earth. Just the other day I had an arrangement in my mind: according to the Old Testament, when God’s people walked together according to the action of God through Moses, the water parted, and the sea, and already before entering the promised land there was a river. We walked on dry ground. According to the New Testament in John the Baptist, through repentance before God we promise God a good conscience before God in every person. That is, the water remains around me, then the Lord suddenly comes (Malachi 3.1), and then I in Jesus (God in me, I and God are one) already walk on the water: that is, those who do not think like God already According to me, the pagans (goyim, peoples not of God), who do not have the righteousness of God, means the power of God. And in Christ Jesus the people of God are truly united into one Body of the Lord, as someone before me answered, the oil is united into one. A wrong mind can no longer prevent me from doing what is right. That is, “the law did not bring anything to perfection, but the best hope is introduced.” The water cycle in nature prolongs life on earth, giving it new colors of the rainbow. After all, with a rainbow, God confirmed his promise that there would be no more worldwide flood (Genesis chapter 9). Even in the Old Testament, the coming of Jesus was promised. And now we live new life. “Behold, I am making all things new,” “If anyone is in Christ, he is a new creature (creation).”
Place 1-2 drops of vegetable oil (or other fat) into four test tubes. Pour 1 ml of ethyl ether into the first test tube, 1 ml of ethyl alcohol into the second, 1 ml of gasoline into the third, and 1 ml of water into the fourth. Shake the contents of the test tubes and let stand. Did the fat dissolve in each test tube? Which substances are good fat solvents and which are bad? Why? What conclusion can be drawn about the solubility of fats based on the experiment?
Conclusion:
Experiment No. 6 Addition of bromine to oleic acid
Add 3-4 drops of bromine water and 1 drop of oleic acid to the test tube and shake vigorously. Bromine water becomes discolored.
(CH 3)-(CH 2) 7 -CH=CH-(CH 2) 7 – COOH + Br 2 → (CH 3)-(CH 2) 7 -CHBr -CHBr -(CH 2) 7 – COOH
(dibromostearic acid)
Experiment No. 7 Oxidation of oleic acid with potassium permanganate
Place 2 drops of oleic acid, sodium carbonate solution and potassium permanganate solution into a test tube. When the mixture is shaken, the pink color disappears. What does the discoloration of bromine water and potassium permanganate solution indicate?
conclusion:
(CH 3)-(CH 2) 7 -CH=CH-(CH 2) 7 –COOH +[O]+HON→(CH 3)-(CH 2) 7 -CH – CH -(CH 2) 7 – UNS
dihydroxystearic acid
Experiment No. 8 Dissolving soap in water.
Place a piece of soap (approximately 10 mg) into a test tube, add 5 drops of water and thoroughly shake the contents of the test tube for 1-2 minutes. After this, the contents of the test tube are heated in a burner flame. Sodium and other alkaline soaps (potassium, ammonium) dissolve well in water.
Test questions on the topic “Carboxylic acids”:
1Carry out the following transformations: C 2 H 6 → C 2 H 5 Cl → C 2 H 5 OH → CH 3 COH → CH 3 COOH
2.How many grams of magnesium and acetic acid required to produce 6 liters of hydrogen.
3. Write the reaction equations for the production of succinic acid from monochloroacetic acid?
4.Write the reaction equations and name the compounds formed:
a) lactic acid + ethyl alcohol
b) lactic acid + sodium hydroxide
c) lactic acid + acetic acid
5. Write the structural formula of palmitodistearin
Laboratory work No. 9 Amino acids. Squirrels.
Proteins contain carbon, hydrogen, oxygen, nitrogen, sulfur, phosphorus and other elements. The molecular weight of a protein can reach hundreds of thousands of carbon units. Proteins are unstable compounds; they are easily hydrolyzed under the influence of acids, alkalis or enzymes. The end products of protein breakdown are amino acids of various compositions.
Amino acids can be considered as derivatives of carboxylic acids in which the hydrogen atom in the radical is replaced by an amino group:
Amino acids simultaneously have two types of functional groups: a carboxyl group, which carries acidic properties, and an amino group, which carries basic properties. Amino acids exhibit amphoteric properties, i.e., the properties of both acids and bases, therefore proteins also exhibit amphoteric properties, since they are built from amino acid residues.
Proteins dissolve in various solvents. Many proteins dissolve in water, some in solutions of neutral salts, alkalis or acids.
Under certain conditions, proteins can precipitate, and the precipitation can be reversible or irreversible. The ability of proteins to precipitate under various conditions is used to detect and separate them. Color reactions to proteins are also used to detect proteins. These include xanthoprotein, biuret and other reactions.
Reagents. Protein solution; aminoacetic acid solution; sulfuric acid (conc.); nitric acid (conc.); hydrochloric acid (conc.); sodium hydroxide, 20% solution; lead acetate, 10 and 20% solutions; copper sulfate (saturated and 1% solutions) CuSO 4 ; ammonia (conc.) NH 3; sodium chloride NaCl, 10% solution; ammonium sulfate, saturated solution (NH 4) 2 SO 4; phenolphthalein; litmus paper, methyl orange; litmus red. aminoacetic acid, 0.2N. solution; copper (II) oxide CuO, powder; caustic soda, 2 N. NaOH solution.
Equipment. Dry test tube; glass rod, test tube with gas outlet tube.
Experience No. 1.Formation of copper aminoacetic salt acids
Reagents and materials:
A little copper oxide CuO powder and 4 drops of aminoacetic acid solution are placed in a test tube and heated in a burner flame, shaking the contents of the test tube. The test tube is placed on a stand for some time to allow excess black copper oxide powder to settle. Add 1 drop of sodium hydroxide solution to the settled blue solution. The solution remains clear.
Amino acids are characterized by the formation of copper salts, colored blue.
α-Amino acids give colored internal complex salts with copper, which are very stable:
ExperienceNo. 2. Effect of amino acids on indicators
Pour 0.5 ml of aminoacetic acid solution into three test tubes and add phenolphthalein to the first, methyl orange to the second, and litmus to the third. The color of indicators does not change. Why are aqueous solutions of monoamino acids neutral with respect to indicators?
Conclusion:
ExperienceNo. 3. Protein coagulation when heated
A small amount of protein solution is placed in a test tube and heated to a boil in a burner flame. Observe protein precipitation in the form of flakes or cloudiness. What explains this? Dilute the solution with water. Does the precipitate dissolve? if not, why not? Cool the protein solution slightly for use in the next experiment.
Conclusion:
Experience No.4. Salting out proteins with sulfateammonium
Pour 1-1.5 ml of protein and ammonium sulfate solution into a test tube and shake the mixture and heat to a boil in the burner flame. The liquid becomes cloudy, and the amount of coagulated protein increases sharply. the addition of neutral salts facilitates and accelerates the coagulation of proteins when heated. Protein coagulation is a process of irreversible precipitation, since protein molecules change their structure.
ExperienceNo. 5. Precipitation of proteins with heavy saltsmetals
Pour 1-2 ml of protein solution into two test tubes and slowly, drop by drop, while shaking, pour a saturated solution of copper sulfate into one of them, and a 20% solution of lead acetate into the other. A flocculent sediment or turbidity forms. Salts of heavy metals precipitate proteins from solutions, forming salt-forming compounds insoluble in water; with copper salts - a blue precipitate; with lead salts - a white precipitate.
ExperienceNo. 6. Precipitation of proteins by mineralsacids
Pour 1 ml of protein solution into three test tubes. Carefully add concentrated nitric acid to the test tube containing the protein solution so that the acid does not mix with the protein. A ring of white flaky sediment forms where the two liquids come into contact. Repeat this experiment with concentrated sulfuric and hydrochloric acids. Proteins form salt-like compounds with concentrated acids and at the same time cause protein coagulation. in most cases, the precipitate that forms is soluble in an excess of concentrated acids (except nitric acid).
ExperienceNo. 7. Color reactions to proteins
1 Xanthoprotein reaction. The xanthoprotein reaction indicates the presence of amino acids containing benzene nuclei, such as tyrosine, in the protein. When such amino acids interact with nitric acid yellow-colored nitro compounds are formed
Add 5-6 drops of concentrated nitric acid to 1 ml of protein solution until a white precipitate or cloudiness from the coagulated protein appears. Heat the reaction mixture until the precipitate turns yellow. During the hydrolysis process, the precipitate dissolves. Cool the mixture and carefully add to it, drop by drop, excess concentrated sodium hydroxide solution NaOH. The color turns orange, which indicates the formation of more intensely colored anions.
2 Biuret reaction. Using the biuret reaction, the presence of peptide groups (-CO-NH-) in protein molecules is detected. Proteins with copper salts give a red-violet color due to the formation of complex compounds.
Pour 1-2 ml of protein solution, 20% sodium hydroxide into a test tube. Then add 3-4 drops of a diluted, almost colorless solution of copper sulfate (CuSO*5H 2 O) and mix the contents thoroughly. The liquid turns purple.
Test questions on the topic “Amino acids”
1. Briefly describe each structure of a protein molecule.
2..Make a diagram reflecting the transformation of food proteins in the human body.
3. Briefly describe the uses of proteins.
4.What determines the specific biological activity of a protein molecule? In what cases can it be lost?
5.What types of protein hydrolysis do you know?
LABORATORY WORK No. 10.PROPERTIESMONOSACHARIDES
With respect to hydrolysis, carbohydrates are divided into two main classes: simple carbohydrates, or monosaccharides (glucose, fructose, galactose), and complex sugars, or polysaccharides. Complex carbohydrates, in turn, are divided into two main groups: sugar-like carbohydrates (sucrose, lactose, maltose) and non-sugar-like carbohydrates (starch, fiber). Of the monosaccharides, the most important are glucose and fructose, the chemical properties of which are determined by the peculiarities of their structure. Sugar-like complex carbohydrates have a sweet taste, dissolve in water, and break down into monosaccharides during hydrolysis. Non-sugar-like complex carbohydrates do not have a sweet taste; upon hydrolysis they also break down into monosaccharides.
Reagents. Glucose, 20% and 2% solutions; Selivanov's reagent; crystalline sucrose and 10% freshly prepared solution; lactose, 10% solution; Fehling's liquid (I); sulfuric acid, 10% solution; ammonia solution, 2.5% NH 3 *H 2 O; sodium hydroxide NaOH, 1% solution; silver nitrate, 1% AgNO3 solution;
Equipment. Glass with a capacity of 100 ml; water bath; funnel; filter paper; .
Experience No. 1. Oxidation glucose with ammonia solution silver oxide (silver mirror reaction)
Pour 1-2 ml of ammonia solution into a test tube and add 1 ml of silver nitrate AgNO 3; First, a brown precipitate of silver oxide precipitates, which then dissolves in an excess of ammonia solution ([Ag(NH 3) 2 ]OH). Add 2 ml of a 20% glucose solution and a few drops of 2% sodium hydroxide to the prepared ammonia solution of silver oxide and carefully heat the resulting mixture until the solution begins to turn black. Further, the reaction proceeds without heating and metallic silver is released on the walls of the test tube in the form of a mirror coating.
glucose gluconic acid
Experience No. 2. Oxidation of glucose with Fehling's reagent
3 drops of glucose solution and a drop of Fehling's reagent are introduced into the test tube. Holding the test tube at an angle, carefully heat the top of the solution. in this case, the heated part of the solution turns orange-yellow due to the formation of copper (I) hydroxide, which subsequently turns into a red precipitate of copper (I) oxide Cu 2 O.
oxidation with Fehling's reagent serves as a qualitative reaction to glucose.
Exercise: write the equation for this reaction and draw a conclusion
Experiment No. 3 Resinization of glucose with alkali
Place 4 drops of glucose solution in a test tube and add 2 drops of sodium hydroxide solution. heat the mixture to a boil and boil gently for 2-3 minutes. The solution turns yellow and then turns dark brown. When heated with alkalis, monosaccharides become resinous and turn brown. The resinization process leads to the formation of a complex mixture of substances.
Experiment No. 4 Selivanov’s reaction to ketosis
A crystal of resorcinol, 2 drops of hydrochloric acid and 2 drops of fructose solution are placed in a test tube. The contents of the test tube are heated until boiling. the liquid gradually turns red.
When heated with concentrated mineral acids, hexose molecules gradually break down, forming a mixture of various products (hydroxymethylfurfural is also one of the products), which forms a colored compound with resorcinol. This reaction allows one to quickly detect the presence of ketohexoses in a mixture of sugars.
Test questions on the topic “Properties of monosaccharides and disaccharides”
What compounds are called monosaccharides?
Based on what experiments can we draw a conclusion about the structure of glucose?
During alcoholic fermentation of glucose, 112 liters of CO 2 were released. How much ethyl alcohol did you get and how much glucose did it take?
4.Using the text of the textbook paragraph, prepare written answers to the following questions: a) What are physical properties glucose? b) Where does glucose occur in nature? c) What is the molecular formula of glucose
5. Which monosaccharides are called pentoses and which hexoses?
6. Which forms of sugars are called furanose and which are pyranose
7. What signs are the basis for determining the right and left isomers of sugars by their chemical string?
LABORATORY WORK No. 11 PROPERTIESPOLYSACCHARIDES
Reagents. Starch, powder and solution; sucrose solution; potato; Rye bread; potato; iodine solution; sulfuric acid, 20% solution of H 2 SO 4 I (conc.); sodium carbonate Na 2 CO 3; calcium carbonate CaCO 3 ;; ammonia, 1% solution NH 3 * H 2 O; Fehling's liquid (I);
Equipment. Glass with a capacity of 100 ml; funnel; water bath; porcelain cups - 2 PC.; mortar and pestle; glass rod, filter paper; cotton wool
Experiment No. 1. Interaction of starch with iodine. Qualitative reaction to starch.
Place 2 drops of starch paste and 1 drop of iodine solution into a test tube. The contents of the test tube turn blue. The resulting dark blue liquid is heated to a boil. The color disappears, but appears again upon cooling.
Starch is a mixture of two polysaccharides - amylose (20%) and amylopectin (80%). Amylose is soluble in warm water and gives a blue color with iodine. Both amylose and amylopectin are composed of glucose units linked by α-glycosidic bonds, but they differ in the shape of the molecules. Amylose is a linear polysaccharide made up of several
Amylopectin is insoluble in warm water and swells in it, forming a starch paste. Amylopectin, unlike amylose, contains branched chains of glucose residues. Amylopectin with iodine gives a reddish-violet color.
Obtaining starch paste.
We dilute 12 g of starch in 40 ml of cold water to obtain starch milk. Bring 160 ml of water to a boil, pouring starch milk into it while stirring. bring the resulting starch paste to a boil and cool to room temperature
Experiment No. 2. Updateaddition of starch in bread and potatoes.
Place one drop of iodine on a piece of white bread and on a cut of raw potato. How will the color change? Draw a conclusion.
Experience№3. Evidence for the presence of hydroxyl groups in sucrose
Place 1 drop of sucrose solution, 5 drops of alkali solution and 4-5 drops of water into a test tube. Add a drop of copper(II) sulfate solution. The mixture acquires a faint bluish color due to the formation of copper saccharate.
The solution is saved for the next experiment.
Experiment No. 4 Lack of reducing ability in sucrose
The copper saccharate solution is carefully heated to a boil over a burner flame, holding the test tube so that only the upper part of the solution is heated. Sucrose does not oxidize under these conditions, which indicates the absence of a free aldehyde group in its molecule
Experience No. 5Acid hydrolysis of sucrose
Place 1 drop of sucrose solution in a test tube, 1 drop of 2 N. hydrochloric acid, 3 drops of water and carefully heat over the burner flame for 20-30 minutes. Half of the solution is poured into another test tube and 4-5 drops of an alkali solution are added to it (until the alkaline reaction to litmus) and 3-4 drops of water. Then add 1 drop of copper sulfate solution and heat the top of the blue solution to a boil. An orange-yellow color appears, indicating the formation of glucose. To the remainder of the hydrolyzed sucrose solution (first test tube), add a crystal of resorcinol, 2 drops of concentrated hydrochloric acid and heat to a boil. a reddish color appears, indicating the formation of fructose. The sucrose molecule is easily split during hydrolysis into a glucose molecule and a fructose molecule. Both monosaccharides are present in sucrose in cyclic forms. Both glycosidic hydroxyls are involved in creating a bond between them.
In sucrose, the fructose residue is in the form of a fragile five-membered ring - furanose; such complex sugars are very easily hydrolyzed.
Conclusion:
Experience No. 6. Acid hydrolysis of starch
IN 7 3 drops of very diluted, almost colorless iodine water are placed in each test tube. 10 ml of starch paste is poured into a porcelain cup, 5 ml of sulfuric acid solution is added and the contents are mixed with a glass rod. Place the cup with the solution on an asbestos mesh and heat it over a small flame. Every 30 s, take 1 drop of solution with a pipette with a capillary hole and transfer it to another test tube with iodine water. Successive samples show a gradual change in color upon reaction with iodine. Sample Color
First. . Blue
Second. Blue-violet
Third Red-violet
Fourth...... Reddish-orange
Fifth........Orange
Sixth Orange-yellow
Seventh Light yellow (color of iodine water)
The solution is cooled, neutralized with an alkali solution using red litmus paper to a strongly alkaline reaction, a drop of Fehling's reagent is added and heated. The appearance of an orange color proves that the end product of hydrolysis is glucose.
(WITH 6 N 10 ABOUT 5 ) X + xH 2 0 = xС 6 N 12 0 6
starch glucose
When heated with dilute mineral acids, as well as under the influence of enzymes, starch undergoes hydrolysis. Hydrolysis of starch occurs stepwise with the formation of increasingly simple carbohydrates.
The scheme for the gradual hydrolysis of starch is as follows:
(WITH 6 N 10 ABOUT 5 ) X → (C 6 N 10 ABOUT 5 )у →(WITH 6 N 10 ABOUT 5 ) z → WITH 12 N 22 0 11 → WITH 6 N 12 ABOUT b
soluble starch dextrins maltose glucose
The first product of hydrolysis - soluble starch - does not form a paste; with iodine it gives a blue color. Upon further hydrolysis, they form dextrins- simpler polysaccharides, which with iodine give a color from blue-violet to orange. Maltose and then glucose do not change the normal color of iodine.
Experience No. 7. Fiber or cellulose
Fiber is the basis of individual organs of all plants, their skeleton. It is built in the same way as starch - from a large amount of glucose residues. Individual glucose units are linked to each other in cellulose through beta-glucosidic hydroxyls.
The difference in the mutual adhesion of glucose molecules in starch and fiber leads to sharp differences in some of their properties. Fiber is dissolved in an ammonia solution of copper oxide hydrate (Schweitzer's reagent). At the same time, its molecules are partially split into smaller fragments. If such a solution is neutralized with acid, the fiber will again appear in the form of a flocculent mass, but with a slightly changed length and structure of the molecules.
After a short treatment with strong sulfuric acid, the fiber dissolves, forming a sticky mass - amyloid. Amyloid is stained blue with iodine. After treatment with sulfuric acid, filter paper becomes stronger and translucent. This is explained by the fact that amyloid glues individual cellulose fibers (plant parchment) together.
B. Preparation of vegetable parchment a. Immerse half a strip of filter paper in a cup with 80% sulfuric acid for 30-40 seconds. Then immerse the paper in a vessel with water and finally rinse it in an ammonia solution. Compare the untreated and acid-treated parts of the paper strip (transparency, strength). Be careful when performing this experiment; Do not splash sulfuric acid when transferring the paper into water!
Record the results of the experiment.
Test questions on the topic “Properties of polysaccharides”
1.What compounds are called polysaccharides
2.What compounds are called disaccharides?
3..Using the text of the textbook paragraph, prepare written answers to the following questions:
a) What are the physical properties of cellulose?
b) Where does cellulose occur in nature? c) What is the formula of the elementary unit of the cellulose macromolecule?
d) what is the main difference between starch, glycogen and fiber?
4. Make a diagram showing the use of starch.
5.List the chemical properties of cellulose.
6. What is called invert sugar?
Laboratory work No. 12Heterocyclic compounds
Reagents and materials: freshly prepared furfural; silver nitrate, 0.2 N. solution; ammonia, 2 N. solution; fuchsinous acid; aniline; phloroglucinol; hydrochloric acid (^=1.19 g/cm3); Glacial acetic acid. mucus acid; ammonia, concentrated solution; glycerol; hydrochloric acid (ρ=1.19 g/cm3). indigo (finely ground powder); sulfuric acid (ρ=1.84 g/cm 3); tin(II) chloride, 1 N. solution in hydrochloric acid medium; caustic soda, 1 N. solution.
Equipment: pine splinter, glass rod. white fabric; filter paper; water bath; mortar and pestle.
ExperienceNo. 1. Furfural reactions
Equipment: watch glass; glass rod; filter paper.
Place 2 drops of furfural and 8 drops of water into a test tube and shake until furfural is completely dissolved.
Reaction with fuchsinous acid. Place 4 drops of fuchsinous acid and a drop of furfural solution on a watch glass and mix with a glass rod. After some time, a slightly noticeable pink color appears.
Reaction with silver ammonia. A drop of silver nitrate and a drop of ammonia solution are placed on a watch glass. A precipitate of silver hydroxide precipitates. Add another drop of ammonia and obtain a clear solution of complex silver salt [Ag(]NНз) 2 ]ОН.
A drop of furfural solution is added to the silver ammonia solution. Free silver appears on the glass in the form of a black spot or silvery coating.
3. Reaction with aniline. Mix a drop of aniline with a drop of acetic acid on a watch glass. A strip of filter paper is moistened with the resulting solution and a drop of furfural is applied to it. A pink-red spot appears.
4. Reaction with phloroglucinol. 3 drops of furfural solution, 1 drop of hydrochloric acid and 2 phloroglucinol crystals are placed in a test tube. When heated, the mixture turns dark green. Furfural has the properties of aromatic aldehydes. It easily gives the “silver mirror” reaction, colors fuchsinous acid, and forms phenylhydrazone.
The color reactions of furfural with aniline and phloroglucinol are based on a condensation reaction. Furfural in the presence of hydrochloric or acetic acid gives colored condensation products with aniline, benzidine, resorcinol, xylidine.
ExperienceNo. 2. Preparation of pyrrole.Qualitative reaction to pyrrole
(Experiencecarry outVexhaustcloset!)
Place several crystals of mucus acid and 2 drops of ammonia solution into a test tube and thoroughly mix the contents of the test tube with a glass rod. Add 2 drops of glycerin and mix the mixture again. The test tube is carefully heated in a burner flame. A pine splinter is moistened with 1 drop of hydrochloric acid and added to the upper part of the test tube, continuing to heat it. Pyrrole vapor turns pine splinters red.
When ammonia is added, the ammonium salt of mucus acid is obtained, which then decomposes. The decomposition products include pyrrole. Glycerin affects the course of the reaction, making it more uniform. Pyrrole is easily tarred by acids, turning red.
ExperienceNo. 3. Properties of indigo
1. Solubility of indigo in water. Place indigo powder on the tip of a microspatula into a test tube and add 5-6 drops of water. The contents of the test tube are carefully
shake at room temperature and then heat in a burner flame. One drop of the resulting mixture is applied to a strip of filter paper - a colorless spot is formed, in the center of which blue indigo powder settles. Indigo does not dissolve in water, as in most common solvents.
2 “Vubic” dyeing. Place 5 drops of a solution of tin(II) chloride into a test tube and add a solution of sodium hydroxide drop by drop until the precipitate formed is dissolved. In a small mortar, carefully grind several indigo crystals with 5-6 drops of water. Using a pipette, transfer 2 drops of the resulting suspension into a test tube with sodium stannite solution and heat the test tube in a boiling water bath until the reaction mixture becomes clear.
In received alkaline solution white indigo, place a small strip of white cloth, previously washed and wrung out. The fabric is thoroughly soaked in a solution of reduced indigo, then wrung out and left in the air. The fabric first takes on a green color and then blue.
Blue indigo is a “vat” dye; in an alkaline environment, blue indigo is reduced to white indigo, which has a phenolic character and is soluble in alkalis. An alkaline solution of white indigo is called a "cube". The fabric is dipped into such a solution, soaked in the solution and then left in the air to “ripen.” On fabric fibers, white indigo is oxidized by air oxygen into insoluble blue indigo.
blue indigo white indigo
Experience No. 4. Oxidation of indigo with a strong oxidizing agent
When indigo is oxidized with a strong oxidizing agent, isatin is obtained, which has a yellow color in solutions (solid isatin is red):
Pour about 1 ml of indigo carmine solution and 5-10 drops of concentrated nitric acid into a test tube. What is observed? How did the color of the solution change?
Write down the result of the experiment
indigo Isatin
Test questions on the topic “Heterocyclic compounds”
1.What compounds are called heterocyclic
2. write the formulas and names of the most important five-membered heterocycles
2. write the formulas and names of the most important six-membered heterocycles
Our body has learned to store all the main components of nutrition in reserve.- yes, just in case. It stores sugar in the liver, proteins in the stomach, but the place chosen for fats is under the skin. Do you want to lose weight? We'll have to go to war on our own body! To win, you must fight skillfully. This article will teach you a lot!
Fats... What is it? Where do they come from? Why are they deposited under the skin? And in general, why are they needed? Or maybe they shouldn't be eaten? It sounds reasonable, because fat causes us so many problems with our figure!
The first stage of fat conversion: eatingThis is all clear: we sat down at the table and loaded ourselves with food. So, the “processing” of fats by the body begins in your mouth, when the salivary glands secrete saliva saturated with special digestive enzymes. Next, it would seem, the stomach should join in this work. Oddly enough, fats are not his profile. So he simply passes them through himself and sends them further into the intestines. And here the fats will be digested and absorbed into the blood. By the way, why do we need these same fats? And isn't it better not to eat them at all?
Let's give the floor to science- Fats are the body's energy fuel
- Fats are vital as a building component of skin, hair, nails...
- Fats are the “raw materials” for the production of hormones.
Fats are unlike carbohydrates and proteins in that they do not dissolve in water. It turns out that the water needs to be replaced with something, right? Our body secretes bile specifically for the sake of fats. Complete dissolution of fats is too tough for her. But she knows how to “split” fats into microscopic drops - triglycerides. And the intestines can cope with them.
Word to scienceA triglyceride is three fatty acid molecules “glued” to a glycerol molecule. In the intestines, some of the triglycerides combine with proteins and, together with them, begin their journey through the body.
The third stage of fat conversion: the journey
Yes, triglycerides cannot travel on their own. They definitely need a vehicle called “lipoprotein”. Lipoproteins are different, and each has its own task.
- Chylomicrons are formed in the intestines from fats and carrier proteins. Their task is to transfer fat obtained from food from the intestines into tissues and cells.
- Lipoproteins with very high density– also transport fat to various tissues and cells, but take it exclusively in the liver.
- Low-density lipoproteins also deliver fats from the liver to the body tissues. What's the difference? And the fact is that, along the way, these lipoproteins “grab” cholesterol from the intestines and distribute it throughout the body. So if cholesterol blood clots have formed somewhere in your vessels, threatening cardiovascular disease, then the culprit is low-density lipoproteins.
- High-density lipoproteins have one function - exactly the opposite. These lipoproteins, on the contrary, collect cholesterol throughout the body and take it to the liver for destruction. Very useful connections.
These details help to understand that consuming fatty foods does not automatically increase cholesterol levels in the body. A risky situation occurs when the body has too many low-density lipoproteins (the ones that help store cholesterol) and not enough high-density lipoproteins (the ones that help remove cholesterol). And this is a purely genetic factor. There is also an arithmetic factor. This is when you eat so much of this very cholesterol that no lipoproteins are enough to remove it. Here's another scientific discovery. It has been established that cholesterol is especially high in animal fats. But vegetable fats are much healthier in this sense. It would seem that we need to eat less animal fats and more vegetable fats. No matter how it is! The beneficial effect of vegetable fats will only be felt in one case: if you completely replace animals with them.
If the body receives more than it needs, then an enzyme called lipase comes into play. Its task is to hide everything unnecessary inside fat cells.
Word to scienceLipase is a kind of key that opens the doors of fat cells towards fats. Fat cells can take in a lot of fat and swell like a balloon. This is precisely the answer that you are getting fat. If one fat cell or even a hundred increases, no one will notice it. However, if you eat too much fat, the myriad of fat cells lying under the skin will swell at once. And you can’t hide this from view. Moreover, lipase can give the command to multiply fat cells. And he will also fill them to capacity with fat. The worst part is that fat cells cannot be destroyed. When you start to lose weight, lipase “opens” the fat cells and releases the fat out, and then it “burns out” during exercise. You look in the mirror: not a drop of fat! Meanwhile, all the fat cells are there, but they just look like punctured balloons. As soon as you give up sports, lipase begins to fill them with fats again.
Why is there so much fat?The body stores not only fats, but also carbohydrates in reserve. Let's say you ate 100 calories worth of carbohydrates. So, the body must spend approximately 23 calories to save the remaining 77 calories. But to save 100 extra “fat” calories, you only need 3 calories. The remaining 97 calories are all yours! So it turns out that fat reserves are always the largest.
Factors contributing to the deposition of fat in the body:
- Age (the older you are, the more readily fat is deposited)
- Gender (women accumulate fat faster)
- Overeating (you eat too much)
- Sedentary lifestyle (you don't need fat energy)
- Excess lipase (heredity factor)
- Nervous stress(contrary to popular opinion, stress makes you fat)
- The habit of eating fatty foods (we are talking about the peculiarities of national cuisine)
- Genetic factors (weight is inherited).
How does exercise help you get rid of extra pounds? And like this. First, the body reacts to physical exercise by consuming glycogen, a pre-stored sugar. And only then, when he spends his “sugar” reserves, does fat deposits come into play. This happens approximately half an hour after the start of aerobic training, i.e. exactly when many people usually fold it.
Changing the figure
There is so much talk about genetics! Like, if your mom was fat, then you cannot escape the same fate. In fact, everything is not so scary. Genes determine 25% of your body composition. Only a quarter! This concerns the number of fat cells and where they accumulate (at the waist or on the hips and buttocks). So, if you really are like Mommy, it’s most likely because you share the same eating habits with her: you overeat just like her. If you start exercising and go on a diet, you will look completely different. By the way, there is no need to shy away from strength exercises. Muscles are a state within a state. Just like the brain, they are awake even when you sleep and expend energy. The more muscle you have, the higher your daily calorie expenditure. Are you afraid of turning into a masculine bodybuilder? A muscle gain of 12-25 kg is visually noticeable. However, bodybuilders have been doing this for decades. May God grant you to gain at least 5-8 kg!
Women who are “apples” have an easier time losing excess fat than women who are “pears.” Fat around the waist is 5 times more malleable than fat around the hips and buttocks. But women with a “pear” figure also have their own methods. First, you need to understand that “burning” fat is part of your overall metabolism. It doesn’t happen that the metabolism is sluggish and the fat is “burned” quickly. So here's your first trick. Eat often - every 2-2.5 hours, but in small portions. This technique really “spins up” the metabolic rate, and therefore “fat burning.” Second. More aerobics! All these 40-45 minute aerobic activities are not for you. At least 4-5 days a week, do aerobics for one and a half to two hours! And further. Fat “burns” oxygen. You need outdoor aerobics. Only in the fresh air! Third. Don’t even try to go on a “strict” diet of less than 1200 calories! It has been proven that such diets, on the contrary, slow down the rate of metabolism, which automatically reduces the rate of “fat burning”!
Where does the body get energy from?The energy you need to lift a barbell or run a cross-country course can come from two sources. These are glycogen (carbohydrates) and fat. So how can you force yourself to lose more fat? Here are the reasons that influence the “choice” of the organism:
- The food you ate before training (if you eat something high in carbohydrates, such as a vegetable salad, porridge, fruit or chocolate, then the body will choose not fat as the main source of energy, but pre-stored sugar - glycogen.)
- Duration of training (the longer you train, the more fat will be burned)
- Intensity of exercise (the higher the load, the more glycogen is consumed)
- Type of exercise (aerobics burns more fat, and exercise equipment burns more glycogen)
- Fitness level (the more athletic experience you have, the more fat you burn)
- Carbohydrates taken during training (if you decide to drink or eat something sweet, you will spend more glycogen).
 02.02.2020 21:05:00 |
