Chemical elements of the card. Instructional cards for practical work in chemistry
Option number 1
1. What do the formulas mean: 2Na; P4; 3Cl2; Mn 2 O 3 ; 2 CuS ; Al (OH) 3 .
Option number 2
1. What do the formulas mean: 5Ca; 2 F 2 ; S8; Fe 2 O 3 ; 3CS2; Mg (OH) 2.
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Option number 3
What do the formulas mean: 2Zn; P4; 3O2; Fe 2 O 3 ; 2CH4; 3HNO 3 3 .
Write the formula of a substance if its molecule consists of:
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Option number 4
What do the formulas mean: 2K; 3S 8; Cl2; Al 2 O 3 ; 2 CuS ; H2CO3.
Write the formula of a substance if its molecule consists of:
a) one calcium atom and two bromine atoms;
b) two boron atoms and three oxygen atoms.
_________________________________________________________________
Option No.5
What do the formulas mean: 2Mg; P4; 3N2; Mn 2 O 7 ; 2SiO 2 ;2HClO 4 .
Write the formula of a substance if its molecule consists of:
b) two potassium atoms and one sulfur atom.
Option No.6
What do the formulas mean: 2Mn; S8; 2NH3; Na2O; 3MgCl 2 ;H 2 SO 4 .
Write the formula of a substance if its molecule consists of:
a) from one atom of copper and two atoms of chlorine;
b) two potassium atoms and one oxygen atom.
_________________________________________________________________
Option No.7
What do the formulas mean: 2Fe; N 2 ; 2P4; Ag2O; 2KOH ;H 3 PO 4 .
Write the formula of a substance if its molecule consists of:
a) one calcium atom and two chlorine atoms;
b) two nitrogen atoms and five oxygen atoms.
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Option No.8
What do the formulas mean: 3Mg; F2; 3O2; Cu2O; 5FeS; K OH.
Write the formula of a substance if its molecule consists of:
a) one iron atom and two chlorine atoms;
b) two sodium atoms and one sulfur atom.
_________________________________________________________________
Option No.9
What do the formulas mean: 2Cu; PH 3 ; 3S2; 2Al2O3; 2 CuS ; 2HNO 3 .
Write the formula of a substance if its molecule consists of:
a) from one atom of mercury and two atoms of chlorine;
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Option number 10
What do the formulas mean: 2Si; 3N2; 3Cl2O; Mn 2 O 3 ; CuSO3; Fe (OH) 3 .
Write the formula of a substance if its molecule consists of:
b) two potassium atoms and one oxygen atom.
Option number 11
What do the formulas mean: 2Na; 2P4; 3Cl2; P 2 O 3 ; 2 CuS ; Al (OH) 3 .
Write the formula of a substance if its molecule consists of:
a) from one nitrogen atom and three hydrogen atoms;
b) from one atom of gold and two atoms of bromine.
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Option number 12
What do the formulas mean: 2Ba; PH 3 ; 3Cl2; Al 2 O 3 ; 2CuCl2; Au (OH) 3 .
Write the formula of a substance if its molecule consists of:
a) one calcium atom and two bromine atoms;
b) two hydrogen atoms and one oxygen atom.
_________________________________________________________________
Option number 13
What do the formulas mean: 2Ca; P4; 3Cl2; Au 2 O 3 ; 2MgS; Al (OH) 3 .
Write the formula of a substance if its molecule consists of:
a) from one atom of barium and two atoms of chlorine;
b) two sodium atoms and one oxygen atom.
_________________________________________________________________
Option number 14
What do the formulas mean: 2K ; P4; 3Cl2; Fe 2 O 3 ; 2CuF ; Ag OH.
Write the formula of a substance if its molecule consists of:
b) two silver atoms and one oxygen atom.
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Option number 15
What do the formulas mean: 2Ba; O 3 ; 3S2; Mn 2 O 3 ; 2CuPO 3 ;HClO 2 .
Write the formula of a substance if its molecule consists of:
a) one magnesium atom and two chlorine atoms;
Option number 16
What do the formulas mean: Ca; P4; 3Cl2; MgCO 3 ; 2 Cu 2 S ; HPO 3 .
Write the formula of a substance if its molecule consists of:
b) two potassium atoms and one oxygen atom.
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Option number 17
What do the formulas mean: 2Na; P4; 3Cl2; MnSO 3 ; 2CuOH; AlPO 4 .
Write the formula of a substance if its molecule consists of:
a) one calcium atom and two fluorine atoms;
b) two phosphorus atoms and five oxygen atoms.
_________________________________________________________________
Option number 18
What do the formulas mean: Ba ; F2; 3NaCl; Mn 2 O 3 ; 2CuCO3; Al (OH) 3 .
Write the formula of a substance if its molecule consists of:
a) from one atom of barium and two atoms of chlorine;
b) two potassium atoms, one carbon atom and three oxygen atoms.
_________________________________________________________________
Option number 19
What do the formulas mean: 2Na; P4; 3CO2; Mn 2 O 3 ; 2CaS; Cu (OH) 2 .
Write the formula of a substance if its molecule consists of:
a) one calcium atom and two iodine atoms;
b) two potassium atoms and one oxygen atom.
_________________________________________________________________
Option No.20
What do the formulas mean: 2Fe; P4; 3O2; Cu2O; 2K 2 S ; Fe (OH) 3 .
Write the formula of a substance if its molecule consists of:
a) one nitrogen atom and three chlorine atoms;
b) two silver atoms and one oxygen atom.
Option No.2 1
What do the formulas mean: 2Na; S8; 3Cl2; Fe 2 O 3 ; 2CS2; Al (OH) 3 .
Write the formula of a substance if its molecule consists of:
a) one magnesium atom and two chlorine atoms;
b) two iron atoms and three oxygen atoms.
_________________________________________________________________
Option number 22
What do the formulas mean: 2Ag; P4; 3Cl2; Mn 2 O 3 ; 2 CuS ; H3BO3.
Write the formula of a substance if its molecule consists of:
a) from one atom of copper and two atoms of bromine;
b) two potassium atoms and one oxygen atom.
_________________________________________________________________
Option No.23
What do the formulas mean: 2Zn; P4; 3Br2; Mn 2 O 3 ; 2 CuS ; Hg (OH) 2 .
Write the formula of a substance if its molecule consists of:
a) one calcium atom and two chlorine atoms;
b) two aluminum atoms and three oxygen atoms.
_________________________________________________________________
Option No.24
What do the formulas mean: 2Ag; 2P4; Cl2; Au 2 O 3 ; 2 CuS ; Fe (OH) 3 .
Write the formula of a substance if its molecule consists of:
a) one carbon atom and two oxygen atoms;
b) two copper atoms and one sulfur atom.
_________________________________________________________________
Option No.25
What do the formulas mean: 2K ; H2; 3Cl2; Fe 2 O 3 ; 2SiO2; Mg (OH) 2.
Write the formula of a substance if its molecule consists of:
a) from one phosphorus atom and three hydrogen atoms;
b) two sodium atoms and one oxygen atom.
Option number 26
What do the formulas mean: 2Zn; P4; 3S2; Al 2 O 3 ; 2CuC; Al (OH) 3 .
Write the formula of a substance if its molecule consists of:
a) one iron atom and three chlorine atoms;
b) from one atom of potassium, one atom of oxygen, one atom of oxygen.
_________________________________________________________________
Option number 27
What do the formulas mean: 2Mn; P2; 3Br2; Fe 2 O 3 ; 2K 2 S ; H2SO4.
Write the formula of a substance if its molecule consists of:
a) one calcium atom and two fluorine atoms;
b) two gold atoms and three oxygen atoms.
___________________________________________________________________
Option No.28
What do the formulas mean: 2B ; P4; 3Cl2; Mn 2 O 3 ; 2 CuS ; Al (OH) 3 .
Write the formula of a substance if its molecule consists of:
a) two iron atoms and three sulfur atoms;
b) two potassium atoms and one oxygen atom.
Instructional cards for practical work in chemistry
Teaching the basics of chemistry at school cannot be improved without the appropriate organization of a school chemical experiment.
A chemical experiment is a source of knowledge about a substance and a chemical reaction - an important condition for activation cognitive activity students, cultivating a sustainable interest in the subject, as well as ideas about the practical application of chemical knowledge.
The implementation of the experimental part of the program requires the teacher to have a high level of comprehensive professional training, a deep understanding of the role of a chemical experiment in the educational process, and creative activity in applying effective methods learning.
Of course, to conduct an experiment at a high scientific, theoretical and methodological level, a variety of equipment is needed, including the latest technical means, but not every school has such equipment in a chemistry room, therefore, for the convenience of teachers and students, these instructional cards are offered for conducting practical works in 8,9,10,11 classes.
Instructional cards are compiled in accordance with the educational line of O. S. Gabrielyan. Many practical works have been compiled taking into account the replacement of chemical equipment and reagents with simpler and more accessible ones for every teacher.
The presented instruction cards contain a brief description of the experiments to be performed, illustrations showing how the device should be assembled for the experiment, which allows students to clearly see the purpose of the work, not be distracted by reading experiments that will not be performed in this work, and also gives an idea of what entries need to be made in a notebook for compiling a report on the work.
In the course of practical work, instructional cards should be on the tables of students and contribute to a clear and well-coordinated work during the experiments.
The proposed practical work makes it possible to expand the use of the experiment in various conditions, to study the features of chemical processes, and to present them in a variety of ways. This approach will allow teachers to use the chemistry experiment more effectively, taking into account the specific conditions of each school.
Practical work
Qualitative determination of carbon, hydrogen and chlorine in organic substances.
Goal of the work:
Equipment:
Reagents:
Determination of carbon and hydrogen.
Assemble the device as shown in the figure.
Carefully heat the substances in the horizontal test tube.
Sketch the setting for the experiment in your notebook.
Write in your notebook the answers to the following questions:
1) How did you prove the presence of hydrogen in the original sample?
Qualitative determination of chlorine.
1. Make from copper wire thin spiral using a rod ballpoint pen.
2. Attach the spiral to the tube holder.
3. Ignite the spiral in the flame of an alcohol lamp, then lower it into a cup of carbon tetrachloride and bring it back into the flame.
4. Write the structural formula of carbon tetrachloride.
5. From the presence of which element the flame is colored in green color?
Conclusion: The presence of what elements in organic matter was proved?
Practical work
Obtaining ethylene and experiments with it
Goal of the work:
Equipment:
Reagents:
1. Assemble the instrument as shown in the figure
2. Sketch in a notebook the setting for the experiment
3. Gently heat the contents of the tube.
4. Pass the released gas through a solution of bromine water, and then through a solution of potassium permanganate
5. Try to ignite the escaping gas .
Do not forget about the rules for working with substances!!!
6. Answer the following questions in writing:
1) Write an equation for the reaction of obtaining ethylene from ethyl alcohol. What type is it?
2) Make an equation for the reaction of the interaction of ethylene with bromine water? How does the color of bromine water and potassium permanganate change?
3) Write an equation for the combustion reaction of ethylene.
Conclusion: What are the properties of ethylene?
Practical work
Alcohols.
Goal of the work:
Equipment:
Reagents:
Burning alcohols
Pour a small amount of ethyl alcohol into a porcelain cup and set it on fire, and then test the burning of isoamyl alcohol.
1. Make the equations of combustion reactions for ethyl and amyl alcohols.
2. What is the difference between the nature of combustion of these alcohols7
Solubility of alcohols in water
Check the solubility of ethyl and isoamyl alcohols in water.
1. What kind of alcohol dissolves in water? What is the reason for the different behavior of alcohols?
2. Why does isoamyl alcohol collect on the surface of the water?
3. What organic matter will also collect on the surface of the water?
Obtaining copper glycerate
From copper (II) sulfate and sodium hydroxide, get copper (II) hydroxide in an empty test tube. Add glycerin to the resulting precipitate.
1. Write an equation for the reaction of obtaining copper hydroxide (II ).
2. Write an equation for the reaction of obtaining copper glycerate (II )
3. How did the color of copper hydroxide change (II ) as a result of a chemical transformation?
Task: Calculate the volume of carbon dioxide that is formed during the combustion of 7 g of 96% ethyl alcohol.
Practical work
Carbohydrates.
Goal of the work:
Equipment:
Reagents:
Experience 1
The interaction of glucose with copper hydroxide (II )
Add a small amount of water to a test tube with glucose powder and dissolve it.
Add a little copper (II) hydroxide to the glucose solution, and then copper sulfate. Heat the test tube with the resulting solution.
What can be said about the solubility of glucose?
Write the reaction of interaction of copper sulfate ( II ) and sodium hydroxide.
Write down the interaction reaction of copper hydroxide ( II ) with glucose.
Note the color change under the appropriate substances.
Experience 2
Preparation of starch paste and its interaction with iodine
Pour some water into a test tube with starch and shake the mixture. Boil a small amount of water in an empty test tube and pour the starch solution into it. Dilute the resulting paste with cold water and add a few drops of iodine.
What is observed when iodine acts on starch?
Experience 3
Detection of iodine in food products.
Which food has the most starch? How was it discovered?
Conclusion: What is a qualitative reaction to glucose and starch?
Practical work
carboxylic acids
Goal of the work:
Equipment:
Reagents:
Experience 1
The interaction of acetic acid with simple substances.
Add zinc to a test tube with acetic acid. Add iron to another test tube with acetic acid. What are you watching?
Write the equations for the reactions performed. Why do these reactions differ in speed?
Experience 2
Interaction of acetic acid with complex inorganic substances.
a) Add a piece of chalk to acetic acid
b) Pour a little alkali into a test tube, tint it with phenolphthalein and add acetic acid.
c) Add acetic acid to copper (II) oxide and heat until the color changes.
Write the chemical equations for the reactions performed. What classes of inorganic substances can acetic acid interact with?
Obtaining an ester.
The test tube contains a mixture of amyl (pentyl) alcohol, acetic acid and concentrated sulfuric acid. Heat the mixture for a few minutes, and then pour the contents of the test tube into a glass of cold water. Check for the presence of ether by smell.
Write the chemical equation for the reaction
What is this type of reaction called?
What role does concentrated sulfuric acid play in this?
Conclusion: What are the properties of acetic acid?
Practical work No. 1 8th grade
“Safety rules for working in a chemical laboratory. Techniques for handling laboratory equipment and heating devices.
Goal of the work: familiarize yourself with the safety rules when working in the chemistry room, laboratory equipment and methods of handling it.
Equipment : Laboratory tripod with ring and foot, spirit lamp, test tube holder, flasks, glasses, funnel, porcelain dishes, matches.
Note:
Work algorithm:
1st stage of work: The study of safety precautions when working in the chemistry room.
2nd stage of work : The structure and handling of the laboratory rack.
Study the structure of the laboratory rack using p.106.
Assemble a tripod for work and disassemble.
Sketch the structure of the tripod, mark its purpose in a notebook.
3. stage of work: The structure of the spirit stove, methods of working with it.
1. Study the structure of the spirit lamp using page 107.
2. Learn how to handle a spirit lamp using the instructions provided by your teacher.
3. Study the structure of the alcohol lamp flame, find out in which zone of the flame heating should be carried out and why.
4. Heat water in a test tube, following the methods of working with an alcohol lamp.
5. In a notebook, draw a spirit lamp and indicate its parts, note the purpose of the spirit lamp and the rules for heating.
4. stage of work: Familiarity with and handling of laboratory equipment and utensils.
Carefully follow the teacher's story, in a notebook draw a conclusion about how to handle equipment and utensils.
Conclusion:
Pay attention to the design of the table in the notebook, write down the drawings carefully.
Practical work №2 8th grade
"Observations on the changes that occur with a burning candle, and their description."
Goal of the work: study the phenomena that occur when a candle burns.
Equipment : a candle, matches, a curved glass tube, a glass slide, a holder, a test tube, a glass tube with a drawn end in a rubber pear, two chemical beakers of different capacities.
Note: 1. Remember the rules of behavior and safety precautions, physical and chemical phenomena, their difference, carefully listen to the instructions of the teacher.
Work algorithm:
1st stage of work: Study of the shape of the flame.
1. Light a candle and determine the shape of the flame, remember what zones the flame has, why is the candle used as a light source?
2nd stage of work: Phenomena that occur when a candle burns.
1. Review the progress of the step using p.110.
3. What phenomenon occurs when candle paraffin melts?
3. stage of work: Detection of combustion products in a flame.
A) Carbon detection
1. Fix the slide in the holder and bring it into the dark zone of the flame, explain what appeared there.
B) Hydrogen detection
1. Fix a dry test tube turned upside down and hold it over a candle flame until fogging, explain the observed phenomenon.
4. stage of work: Effect of air on candle burning.
1. Review the progress of the step using page 111.
2. Put the step into practice.
3. Explain how air affects the burning of a candle?
Conclusion:
1. Pay attention to the design of the table in the notebook, draw conclusions carefully, clean the workplace after yourself.
Practical work No. 3 8th grade
"Soil and Water Analysis".
Target: to study the composition of the soil and some characteristics of water samples from different sources, to master the practical methods of working with substances.Equipment : laboratory stand, test tube stand, test tube with stopper, test tube, magnifying glass, filter paper, funnel, glass plate, glass rod, tweezers, pipette, transparent flat-bottomed glass cylinder 2-2.5 cm in diameter, 30-35 cm high (or 250 ml graduated cylinder without plastic stand), conical flask with stopper, heater, matches, indicator paper (blue and red), printed text sheet.Reagents: soil samples, pond water, tap water, distilled water.
Note:
Learn the safety regulations using p.105.
2. Listen carefully to the teacher's instructions.
Experience 1.
Mechanical analysis of the soil.
We place the soil in a test tube (a column of soil 2-3 cm high).
Add distilled water, the volume of which should be 3 times the volume of the soil.
Stopper the tube and shake vigorously for 1-2 minutes.
Using a magnifying glass, we observe the sedimentation of soil particles and the structure of the sediment.
Observed phenomena:
substances contained in the soil are deposited with different speed. After some time, the contents will delaminate: heavy sand will settle below, there will be a muddy layer of suspended clay particles above, a layer of water even higher, and mechanical impurities (for example, sawdust) on its surface.
Conclusion:
Soil is a mixture of various substances.
Experience 2.
Obtaining a soil solution and experiments with it.
1. We prepare a paper filter, insert it into a funnel fixed in a tripod ring.
We substitute a clean, dry test tube under the funnel and filter the mixture of soil and water obtained in the first experiment.
Observed phenomena:
the soil remains on the filter, and the filtrate is collected in the test tube - this is a soil extract (soil solution).
Conclusion:
soil contains substances that are insoluble in water
2. Place a few drops of this solution on a glass plate.
Using tweezers, hold the plate over the burner until the water evaporates.
Observed phenomena:
water evaporates, and crystals of substances previously contained in the soil remain on the plate.
Conclusion:
soil contains water-soluble substances.
3. Apply a soil solution to two litmus papers (red and blue) with a glass rod.
Observed phenomena:
a) blue indicator paper changes color to red.
Conclusion:
the soil is acidic.
a) red indicator paper changes color to blue.
Conclusion:
the soil is alkaline.
Experience 3.
Determination of water transparency.
We put a transparent flat-bottomed glass cylinder with a diameter of 2-2.5 cm, a height of 30-35 cm (or a 250 ml measuring cylinder without a plastic stand) on a sheet with printed text.
Pour distilled water into the cylinder until the font is visible through the water.
Measure the height of the water column with a ruler.
Observed phenomena:
... cm is the height of the water column.
Similarly, we conduct an experiment with water from a reservoir.
Observed phenomena:
... cm is the height of the water column.
Conclusion:
distilled water is more transparent than water from a reservoir.
Experience 4.
Determination of the intensity of the smell of water.
We fill the conical flask to 2/3 of the volume with the investigated water, tightly close the cork and shake vigorously.
We open the flask and note the nature and intensity of the smell, using the textbook table.
Observed phenomena:
.... (for example, the smell is distinct - unpleasant, intensity - 4 points).
Conclusion:
... (for example, an unpleasant odor can be a reason for refusing to drink).
General conclusion on work
: in the course of this practical work, the composition of the soil was studied, the transparency and intensity of the smell of water were studied, practical methods of working with substances were improved.
Practical work No. 4 8th grade
"Preparation of a sugar solution, with a certain mass fraction."
Goal of the work: learn how to prepare solutions with a certain mass fraction of a solute, make theoretical calculations that can be applied in practice.
Equipment : scales, measuring cylinder, spoon, beaker, glass rod, water, sugar.
Note:
1. Remember the rules of conduct and safety precautions, dissolution processes, formulas for calculation.
2. Listen carefully to the teacher's instructions.
Work algorithm:
1st stage of work: Estimated part.
1. Having received the task from the teacher, make a calculation to perform practical work.
2nd stage of work: Weighing a sample of sugar.
1. On the scales, weigh the required amount of sugar, and pour it into a glass.
3. stage of work: Measurement of the volume of water.
1. Use a measuring cylinder to measure the calculated volume of water and pour it into a glass of sugar.
4. . stage of work: Preparation of a sugar solution with a given mass fraction of sugar.
1. Stir sugar with water with a glass rod until it is completely dissolved.
Conclusion:
1. Pay attention to the design of the table in the notebook, do calculations, drawings carefully.
2. Make the right conclusions on the work.
3. Clean up your workspace.
Practical work No. 5 8th grade
"Signs of chemical reactions".
Goal of the work: To consolidate knowledge about the signs of chemical reactions; continue to develop skills: work with substances and chemical equipment, observe and describe the reactions carried out.
Equipment : Alcohol lamp, test tubes in a rack, tongs, copper wire, hydrochloric acid, marble, sulfuric acid, sodium sulfate, barium chloride, copper oxide (2), spoon, phenolphthalein.
Note:
1. Remember the rules of conduct and safety precautions, signs of chemical reactions.
2. We use reagents according to the requirements and economically.
Work algorithm:
1st stage of work: Ignition of copper wire in the flame of an alcohol lamp.
1. Take a copper wire in tongs and bring it into the flame of an alcohol lamp, heat it up, pay attention to the changes that have occurred with the wire.
2nd stage of work: Interaction of copper oxide (2) with sulfuric acid.
2. Take copper oxide (2) with a spoon, place it in a test tube, add sulfuric acid and heat. What's happening?
3. stage of work: Interaction of marble with hydrochloric acid.
1. Put a piece of marble into a test tube and add hydrochloric acid, what happens?
4. stage of work: Reaction between sodium hydroxide and hydrochloric acid.
1. Put sodium hydroxide solution into a test tube and add phenolphthalein drop by drop, what happened, then add hydrochloric acid solution, what happens?
5. . stage of work: Interaction of sodium sulfate with barium chloride.
1. Place 2 ml of sodium sulfate solution in a test tube and add a few drops of barium chloride, what happens?
Conclusion:
1. What signs of chemical reactions did you observe at all stages of work.
2. Make the correct reaction equations, determining their type and conclusions on the work.
Practical work No. 6 8th grade
"Conditions for the flow of chemical reactions between electrolyte solutions to the end".
Goal of the work: To confirm and consolidate knowledge about the conditions under which chemical reactions between electrolyte solutions go to the end, to form the ability to select electrolyte pairs.
Equipment : Stand with test tubes, spirit lamp, holder, matches, glass slide, CuSO 4 , KCl, NaOH, Na 2 SO 4 , Na 2 CO 3 , HCl, HNO 3 , phenolphthalein.
Note: 1. Remember and follow the rules of conduct and safety.
Work algorithm:
Carrying out reactions between electrolyte solutions:
A) Copper sulfate (2) and sodium hydroxide.
1. Pour 1 ml of copper sulfate solution (2) into a test tube and add sodium hydroxide drop by drop.
B) Potassium chloride and sodium hydroxide.
1. Pour 1 ml of potassium chloride solution into a test tube and add sodium hydroxide drop by drop.
C) Sodium sulfate and hydrochloric acid.
1. Pour 1 ml of sodium sulfate solution into a test tube and add hydrochloric acid drop by drop.
D) Sodium carbonate and hydrochloric acid.
1. Pour 1 ml of sodium carbonate solution into a test tube and add hydrochloric acid drop by drop.
E) Sodium hydroxide and hydrochloric acid.
1. Pour 1 ml of sodium hydroxide solution into a test tube, add phenolphthalein and add hydrochloric acid drop by drop.
E) Sodium sulfate and nitric acid.
1. Pour 1 ml of sodium sulfate solution into a test tube and add nitric acid drop by drop.
Conclusion: 1. What happens at each stage, explain the observed, make the correct reaction equations, conclusions on the work, clean the workplace.
Practical work number 7 8th grade
"Properties of acids, bases, oxides, salts".
Goal of the work: Carry out chemical reactions that characterize the properties of acids, bases, oxides, salts, form the ability to correctly design an experiment, write reaction equations in the light of TED.
Equipment : Test tube rack, glass rod, N 2 SO 4 , Mg, CaO, BaCl 2 , CuSO 4
NaOH, FeCl 3 , blue litmus, spirit lamp, holder.
Note: 1. Remember and follow the rules of conduct and safety precautions, use reagents sparingly, conduct the experiment according to the instructions.
Work algorithm:
Stage 1: Carry out reactions characterizing the properties H 2 SO 4 , having Mg, CaO, KOH, BaCl 2.
1. Pour 1 ml of sulfuric acid into a test tube and add the proposed substances one by one (do not forget to conduct the experiment in one test tube, rinse), what is happening, explain the observed.
2. Write an equation for the dissociation of an acid and an ion exchange reaction between the substances taken.
2nd stage: Get Cu(OH) 2 , perform reactions that characterize its properties.
1. Pour 1 ml of copper sulfate solution (2) into a test tube and add sodium hydroxide solution drop by drop, what happens?
2. Divide the resulting blue precipitate into two test tubes, add sulfuric acid to one, heat the other, what is happening, explain the observed.
3. stage of work: Perform reactions that characterize the properties FeCl 3 and CuSO 4 .
1. Pour a solution of ferric chloride (3) into a test tube and add sodium hydroxide solution drop by drop, what happens?
2. Pour the copper(2) sulfate solution into the test tube and release the iron clip, what happens?
3. Write an equation for the reaction of ion exchange between the substances taken.
Conclusion: Make the correct reaction equations, conclusions on work, clean your workplace.
Practical work No. 8 8th grade
"Solving experimental problems".
Goal of the work: To form the ability to solve experimental problems
Teaching the basics of chemistry at school cannot be improved without the appropriate organization of a school chemical experiment.
A chemical experiment - a source of knowledge about a substance and a chemical reaction - is an important condition for enhancing the cognitive activity of students, fostering a steady interest in the subject, as well as ideas about the practical application of chemical knowledge.
The implementation of the experimental part of the program requires the teacher to have a high level of comprehensive professional training, a deep understanding of the role of a chemical experiment in the educational process, and creative activity in the application of effective teaching methods.
Of course, to conduct an experiment at a high scientific, theoretical and methodological level, a variety of equipment is needed, including the latest technical means, but not every school has such equipment in a chemistry room, therefore, for the convenience of teachers and students, these instructional cards are offered for conducting practical works in 8,9,10,11 classes.
Instructional cards are compiled in accordance with the educational line of O. S. Gabrielyan. Many practical works have been compiled taking into account the replacement of chemical equipment and reagents with simpler and more accessible ones for every teacher.
The presented instruction cards contain a brief description of the experiments to be performed, illustrations showing how the device should be assembled for the experiment, which allows students to clearly see the purpose of the work, not be distracted by reading experiments that will not be performed in this work, and also gives an idea of what entries need to be made in a notebook for compiling a report on the work.
In the course of practical work, instructional cards should be on the tables of students and contribute to a clear and well-coordinated work during the experiments.
The proposed practical work makes it possible to expand the use of the experiment in various conditions, to study the features of chemical processes, and to present them in a variety of ways. This approach will allow teachers to use the chemistry experiment more effectively, taking into account the specific conditions of each school.
Download:
Preview:
Practical work
Soil and water analysis.
Goal of the work:
Equipment:
Reagents:
Experience #1
Mechanical analysis of the soil.
In a test tube with soil, add three times more water stopper and shake vigorously for 1-2 minutes.
1. How does particle settling take place?
2. What color is the sediment?
3. What is the particle structure? (coarse-grained, fine-grained, etc.)
Experience No. 2
Obtaining a soil solution and experiments with it.
A) Prepare the device for filtering, as shown in fig.
Filter the mixture of soil and water obtained in the first
experience.
B) Place a few drops of soil solution on a glass slide and evaporate. What are you watching?
C) Examine the soil solution with indicator paper.
1. Sketch the filtering device
2. What substances contained in the soil solution did you find during evaporation?
3. What medium does the soil solution have?
Experience No. 3
Determination of water transparency.
Place the measuring cylinder on the printed text of the textbook and carefully pour the test water from the flask.
At what height will the font not be visible?
Assess the transparency of the water.
Experience No. 4
Determination of the intensity of the smell of water.
Shake the test water in the flask and check the intensity of the odor.
Rate the smell in points using the table on page 112 in the textbook
CONCLUSION: What can be learned from soil and water analysis?
Practical work
Preparation of solutions and their calculation mass fraction in solution.
Goal of the work:
Equipment:
Reagents:
Task 1
Calculate how many grams of sugar (C 12 N 22 O 11 ) is necessary and what volume of water is required to prepare 60 g of a 4% solution. What is the amount of sugar in the solution?
Solve the problem in your notebook and prepare this solution in a flask using a ready-made sugar sample, sign the label according to the model and stick it.
Task 2
Prepare 50 ml of 6% NaCl solution and calculate the amount and number of molecules of this substance in the solution.
Solve the problem in a notebook and prepare this solution in a flask using a ready-made sample, sign the label according to the model and stick it.
Practical work
Signs of chemical reactions
Goal of the work:
Equipment:
Reagents:
Experience 1
Ignition of copper wire and interaction of copper oxide with sulfuric acid.
1.Fix the copper wire in the holder and ignite in the flame of an alcohol lamp. Clean off any build-up on a piece of foil paper.
What sign of a reaction did you notice?
2. Add sulfuric acid to the copper oxide (black) in the test tube.
Write an equation for this chemical reaction. What type is it?
What is the sign of this reaction?
Experience 2
The interaction of chalk with acid.
Add a small amount of hydrochloric acid to a piece of chalk in a test tube. What are you watching?
Write an equation for the reaction taking place. What type is it?
What is the sign of this reaction?
Experience 3
Interaction of ferric chloride with potassium thiocyanate.
Pour a small amount of ferric chloride into an empty test tube, examine its color and add a little potassium thiocyanate
Write an equation for the reaction. What type is it?
What sign of reaction did you observe?
Experience 4
Interaction of sodium sulfate with barium chloride.
To a clear solution of sodium sulfate in a test tube, add a little barium chloride. What are you watching?
Write an equation for this reaction. What type is it?
What is the sign of this reaction?
Conclusion: What are the characteristics of chemical reactions?
8th grade
Practical work
Ionic reactions
Goal of the work:
Equipment:
Reagents:
Experience 1
Detection of sulfate - ions.
Two test tubes contain salts of sulfuric acid - sodium sulfate and potassium sulfate. Add barium chloride to both tubes until a precipitate appears.
Make ionic equations for these chemical reactions and indicate the color of the precipitates.
Experience 2
Detection of chloride - ions.
Prepare a sodium chloride solution. Using silver nitrate, prove that this salt contains chloride ion.
Write the reaction as an ionic equation, indicating the color of the precipitate.
Experience 3
Detection of sulfate - ions and chloride - ions.
Two test tubes contain solutions of potassium chloride and magnesium sulfate. Using the appropriate reagents, prove that sulfate ions are present in one test tube, and chloride ions are present in the other.
Write ionic equations for the chemical reactions performed, indicating the color of the precipitate.
Experience 4
Determination of the qualitative composition of a substance.
Prepare a solution of copper (II) sulfate, divide it into two test tubes.
Prove that this solution contains copper ions and sulfate ions by obtaining the appropriate precipitation.
Write the reactions performed in ionic form and indicate the color of the precipitates.
Practical work
Conditions for the flow of chemical reactions between electrolyte solutions to the end
Goal of the work:
Equipment:
Reagents:
Experience 1
Reactions with the formation of a precipitate.
a) Add a little alkali to a test tube with copper (II) sulfate.
b) Add barium chloride to a test tube with aluminum sulfate.
Make up the molecular and ionic equations of the reactions performed. Specify the color of precipitation.
Experience 2
Reactions with evolution of gas
To a piece of chalk (calcium carbonate) add a little hydrochloric acid.
Write the molecular and ionic equation for the reaction.
Experience 3
Reactions with the formation of water.
a) Pour a little alkali into an empty test tube and tint it with phenolphthalein, then add sulfuric acid.
b) Pour a small amount of iron(II) sulfate into a test tube, then add alkali. Add sulfuric acid to the resulting precipitate.
Make up the molecular and ionic equations of the reactions performed.
What is the name of the reaction between an acid and a base?
Conclusion: Under what conditions are ion exchange reactions possible?
Solution (formula in-va) ……%
Prepared by: F.I.
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GRADE 10
Practical work
Qualitative determination of carbon, hydrogen and chlorine in organic substances.
Goal of the work:
Equipment:
Reagents:
Experience #1
Determination of carbon and hydrogen.
- Assemble the device as shown in the figure.
- Carefully heat the substances in the horizontal test tube.
- Sketch the setting for the experiment in your notebook.
- Write in your notebook the answers to the following questions:
1) How did you prove the presence of hydrogen in the original sample?
2) The content of what element is evidenced by the turbidity of lime water? Write the appropriate chemical reaction equation.
Experience No. 2
Qualitative determination of chlorine.
1. Make a thin spiral of copper wire using a ballpoint pen.
2. Attach the spiral to the tube holder.
3. Ignite the spiral in the flame of an alcohol lamp, then lower it into a cup of carbon tetrachloride and bring it back into the flame.
4. Write the structural formula of carbon tetrachloride.
5. From the presence of what element does the flame turn green?
Conclusion: (What elements have been proved in organic matter?)
Practical work
Obtaining ethylene and experiments with it
Goal of the work:
Equipment:
Reagents:
1. Assemble the instrument as shown in the figure
2. Sketch in a notebook the setting for the experiment
3. Gently heat the contents of the tube.
4. Pass the released gas through a solution of bromine water, and then through a solution of potassium permanganate
5. Try to ignite the escaping gas.
Do not forget about the rules for working with substances!!!
6. Answer the following questions in writing:
1) Write an equation for the reaction of obtaining ethylene from ethyl alcohol. What type is it?
2) Make an equation for the reaction of the interaction of ethylene with bromine water? How does the color of bromine water and potassium permanganate change?
3) Write an equation for the combustion reaction of ethylene.
Conclusion: What are the properties of ethylene?
Grade 10
Practical work
Alcohols.
Goal of the work:
Equipment:
Reagents:
Burning alcohols
Pour a small amount of ethyl alcohol into a porcelain cup and set it on fire, and then test the burning of isoamyl alcohol.
1. Make the equations of combustion reactions for ethyl and amyl alcohols.
2. What is the difference between the nature of combustion of these alcohols7
Solubility of alcohols in water
Check the solubility of ethyl and isoamyl alcohols in water.
1. What kind of alcohol dissolves in water? What is the reason for the different behavior of alcohols?
2. Why does isoamyl alcohol collect on the surface of the water?
3. What organic matter will also collect on the surface of the water?
Obtaining copper glycerate
From copper (II) sulfate and sodium hydroxide, get copper (II) hydroxide in an empty test tube. Add glycerin to the resulting precipitate.
1. Write an equation for the reaction of obtaining copper (II) hydroxide.
2. Write an equation for the reaction of obtaining copper (II) glycerate
3. How did the color of copper (II) hydroxide change as a result of chemical transformation?
Task: Calculate the volume of carbon dioxide that is formed during the combustion of 7 g of 96% ethyl alcohol.
Grade 10
Practical work
Carbohydrates.
Goal of the work:
Equipment:
Reagents:
Experience 1
Interaction of glucose with copper (II) hydroxide
Add a small amount of water to a test tube with glucose powder and dissolve it.
Add a little copper (II) hydroxide to the glucose solution, and then copper sulfate. Heat the test tube with the resulting solution.
- What can be said about the solubility of glucose?
- Write the reaction between copper (II) sulfate and sodium hydroxide.
- Write down the interaction reaction of copper (II) hydroxide with glucose.
Note the color change under the appropriate substances.
Experience 2
Preparation of starch paste and its interaction with iodine
Pour some water into a test tube with starch and shake the mixture. Boil a small amount of water in an empty test tube and pour the starch solution into it. Dilute the resulting paste with cold water and add a few drops of iodine.
- What is observed when iodine acts on starch?
Experience 3
Detection of iodine in food products.
Check the iodine content of white bread, potatoes and yogurt.
- Which food has the most starch? How was it discovered?
Conclusion: What is a qualitative reaction to glucose and starch?
Practical work
carboxylic acids
Goal of the work:
Equipment:
Reagents:
Experience 1
The interaction of acetic acid with simple substances.
Add zinc to a test tube with acetic acid. Add iron to another test tube with acetic acid. What are you watching?
Write the equations for the reactions performed. Why do these reactions differ in speed?
Experience 2
Interaction of acetic acid with complex inorganic substances.
a) Add a piece of chalk to acetic acid
b) Pour a little alkali into a test tube, tint it with phenolphthalein and add acetic acid.
c) Add acetic acid to copper (II) oxide and heat until the color changes.
Write the chemical equations for the reactions performed. What classes of inorganic substances can acetic acid interact with?
Experience 3
Obtaining an ester.
The test tube contains a mixture of amyl (pentyl) alcohol, acetic acid and concentrated sulfuric acid. Heat the mixture for a few minutes, and then pour the contents of the test tube into a glass of cold water. Check for the presence of ether by smell.
Write the chemical equation for the reaction
What is this type of reaction called?
What role does concentrated sulfuric acid play in this?
Conclusion: What are the properties of acetic acid?
Preview:
Practical work
Obtaining gases and studying their properties.
Experience #1
Obtaining and collecting hydrogen
1. Get hydrogen using zinc and hydrochloric acid.
2. Draw a device for receiving and collecting gas.
3. Make a redox equation for the chemical reaction to produce hydrogen.
4. How to prove the presence of oxygen in a test tube?
Experience No. 2
Obtaining with picking up oxygen.
1. Get oxygen using potassium permanganate.
2. Draw a device for receiving and collecting oxygen.
3. Make a redox equation for the chemical reaction of obtaining oxygen.
4. How to prove the presence of oxygen in a beaker?
Experience No. 3
Receiving from picking up carbon dioxide.
1. Using chalk and hydrochloric acid, get carbon dioxide.
2. Draw a device for receiving and collecting carbon dioxide.
3. Make an ionic equation for the chemical reaction to produce carbon dioxide.
4. How to prove the presence of carbon dioxide in a test tube?
Conclusion: What do the obtained gases have in common and how do they differ?
Grade 11
Practical work
Comparison of properties of inorganic and organic compounds.
Goal of the work:
Equipment:
Reagents:
Experience 1
Salt formation, interaction of organic and inorganic bases with acid and experiments with them.
1. Get copper (II) hydroxide from the available reagents. Add hydrochloric acid to the resulting precipitate. Add alkali solution to the resulting salt solution
Write the equations of the reactions performed in ionic form
2. Get an emulsion of aniline, add hydrochloric acid and then alkali solution.
Write down the equations of the reactions done
What are the similarities between organic and inorganic bases?
Experience 2
Obtaining esters.
1. Heat a mixture of isoamyl alcohol (isopentyl), acetic acid and conc. sulfuric acid until yellow. Then pour the hot mixture into a glass of cold water. Ether collects on the surface.
2. Ignite the mixture of boric acid and ethyl alcohol in a porcelain cup. Ether - triethyl borate burns with a green flame.
Write an equation for obtaining an ester from isoamyl alcohol and acetic acid.
Write the equation for the formation of an ester from boric acid () and ethyl alcohol
Write the combustion reaction for tetraethyl borate:
Grade 11
Practical work
Solving experimental problems in inorganic chemistry
Goal of the work:
Equipment:
Reagents:
Task 1
Given a mixture consisting of potassium chloride, iron sulfate (III). Do experiments with which you can determine chloride - ions and ions
iron (+3).
Task 2
From the available substances: copper (II) sulfate, magnesium sulfate, sodium hydroxide, iron, iron (III) chloride, you will get:
a) iron (III) hydroxide
b) magnesium hydroxide
c) copper
Make the equations of the reactions done in molecular, full and reduced ionic form, consider the processes of oxidation-reduction
Task 3
Crystalline substances are given in three test tubes:
a) ammonium sulfate
b) copper (II) nitrate
c) iron sulfate (II)
Determine what substance is in each test tube.
Write the equations of the reactions performed in molecular, full and abbreviated ionic form.
GRADE 11
Practical work
Solving experimental problems in organic chemistry.
Goal of the work:
Equipment:
Reagents:
Task 1
Using characteristic reactions, recognize the substances in the test tubes:
ethanol
acetic acid
glucose
sugar syrup
glycerol
Task 2
Recognize with the help of the same reagent which of the test tubes contains the solutions:
soap
squirrel
soda
Make up the equations of the reactions done, name the products formed and indicate the number of test tubes in which the substances were located
Grade 11
Practical work
Genetic relationship between classes of inorganic and organic substances.
Goal of the work:
Equipment:
Reagents:
Carry out the following transformations:
a) CuO CuSO 4 Cu(OH) 2 CuO
CuCl 2
b) FeSO 4 Fe(OH) 2 Fe(OH) 3 FeCl 3 Fe(OH) 3
Compose the reactions performed in molecular, full ionic and abbreviated form. Consider redox processes.
Practical work No. 2
The rate of chemical reactions.
chemical balance.
Goal of the work: …………..
Equipment: ………..
Reagents: ……………..
Experience #1
Influence of the nature of reacting substances on the rate of chemical reactions.
1. Put zinc and magnesium metals into two test tubes and add sulfuric acid.
2. Compose the redox reactions of the ongoing processes.
3. Which metal is more active and why?
Experience No. 2
Effect of temperature on the rate of chemical reactions.
1. Pour sulfuric acid solution into two test tubes. Warm up one test tube. At the same time, lower the pieces of iron into both test tubes.
2. Make a redox reaction of the ongoing process.
3. In which test tube is the reaction faster and why?
Experience No. 3
Influence of the concentration of reactants on the reaction rate
1. Pour an equal amount of copper oxide (II) into two test tubes. Add conc. to one tube. sulfuric acid, and in another dilute
2. Write an ionic equation for the ongoing process.
3. In which case is the reaction rate greater?
Experience No. 4
Influence of the surface of reacting substances on the rate of a chemical reaction.
1. Take two test tubes with calcium carbonate (one contains the powder and the other contains a piece of the substance). Add hydrochloric acid to both tubes.
2. Write an ionic equation for the ongoing chemical reaction.
3. In which case does the reaction go faster and why?
CONCLUSION: What conditions affect the rate of chemical reactions?
Grade 11
Practical work No. 4
Hydrolysis
Goal of the work:
Equipment:
Reagents :
Task 1
Using indicator paper, recognize the salts in the test tubes: Na 2 SO 4 , K 2 CO 3 , MgSO 4
Write : 1. What salts were in each test tube
№ 1 - , № 2 - , № 3 -
2. Make up the chemical equations of hydrolysis for salts in which it is possible.
Task 2.
Prepare a sodium carbonate solution, divide it into two test tubes, add a few drops of phenolphthalein to both. Then dilute one of the solutions with a little water.
1. Write a hydrolysis equation for a given salt.
2. How does the addition of water affect the course of hydrolysis?
Task 3
Divide the available sodium acetate solution into two test tubes, and add a small amount of phenolphthalein to both. Heat one test tube. What do you observe?
1. Write the hydrolysis equation.
2. How does temperature affect the course of hydrolysis?
Task 4
Add some iron(III) chloride to the magnesium powder. What are you watching?
Make up the reaction equations for the ongoing processes (salt hydrolysis and the interaction of magnesium with hydrolysis products)