Work program of the course of extracurricular activities "Laboratory of a young chemist" work program in chemistry (grade 8) on the topic. Start in science If you increase the mass of the pendulum, then how will the
Sharonova Selena Mikhailovna
Physics teacher
Samara Region
Togliatti
Article on the topic
"The chemical laboratory and its importance in the development of students in the study school course chemistry in the system of extracurricular activities "
Currently modern education going through a crisis. The teachers were completely new situation- the experience of the previous generation is passed on to the next, but he does not need that one.
Extracurricular activities are motivated educational activities, outside the framework of basic education, carried out by educational programs that have specific educational goals and objective, measurable results that allow the student to maximize his interests in knowledge and creativity.
A laboratory is a special room in which any research is carried out. For example, in a biological laboratory, plants and microorganisms are grown, animals are kept. The physical laboratory studies electricity, light, phenomena in liquids and gases; processes occurring with solids. A chemical laboratory is a large room where chemical equipment is located: special furniture, instruments, utensils for working with substances. The properties and transformations of substances are studied here.
The chemistry lab creates a deep and sustained interest in studentsto the world of substances and chemical transformations, to acquire the necessary practical skills. The chemistry laboratory allows the child to go beyond the subject and get acquainted with what he will never learn about in the classroom. Experimentally, children learn, master new material, learn to analyze and evaluate their actions.
When performing certain work in the laboratory, practical knowledge and skills in chemistry are formed that can help a child in his Everyday life... Cognitive activity is also formed, the desire to research work within the natural scientific cycle and provides preliminary preparation for continuing education and the conscious choice of a profession.
The experiments carried out in the chemical laboratory educate and develop not only creative activity, but also the initiative and independence of students, while forming positive, healthy, environmentally friendly everyday habits. Implemented labor education by working with reagents, equipment, in the process of working on setting up experiments and processing their results. Studying the equipment, various simple experiments, students fall into the stream of success, where they increase their own self-esteem and the status of students in the eyes of peers, teachers and parents.
Performing laboratory work, experiments, research, children improve their skills in chemical experiment and acquire certain skills in research and project activities, master the methods of finding the necessary information. At the same time, not only a cognitive interest in the subject of chemistry develops, Creative skills, a positive attitude to learning by creating a situation of surprise, amusement, paradox, a scientific worldview is formed.
Before performing any experimental work in a chemical laboratory, it is necessary to familiarize the child with the entire instrument, preferably in a play version.
Let's get together with the first assistants - chemical devices and utensils. Each subject has its own responsibility, and images of these devices can be found in any chemistry textbook.
A test tube is a long glass vessel, similar to a tube, sealed at one end. It is made of colorless refractory glass, and it can be quite strong
heat a liquid or solid, it can collect gas. And it is made long so that it is convenient to hold it in your hand, fix it in a tripod or holder. Experiments can be carried out in a test tube without heating, by carefully pouring or pouring substances. A warning must be given not to drop the test tube: the glass is fragile.
Clamp or holder for a test tube or small vessel. You can squeeze them into it with a long heating of the substance so as not to burn your fingers.
A rack for test tubes, or a stand for them. It can be metal or plastic, and you, of course, have seen it, if it happened in the clinic to donate blood from a finger. If the tripod is made of plastic, never put a hot test tube in it: you will ruin the bottom of the tripod and the test tube.
An alcohol lamp is a special device for burning alcohol. With the heat that the burning alcohol gives, we heats the substances when we need it. We light the spirit lamp only with a match, and extinguish it, covering it with a cap. Do not blow on a burning spirit lamp and carry it - it is dangerous. And even when the test tube is heated on an alcohol lamp, the bottom of the test tube must not touch the wick - the test tube may burst. The container into which the alcohol is poured is wide and stable and has thick walls. This is important to ensure that working with the spirit lamp is safe.
Some laboratories use gas burners to heat substances. They give a hotter flame, but they need to be handled carefully - after all, gas.
Flasks are glass vessels, somewhat resembling bottles in shape. They can temporarily store substances, conduct chemical experiments, prepare solutions. Flasks,
depending on the shape, they can be conical, round, flat-bottomed, and round-bottomed. In flasks with a round bottom, you can heat substances for a very long time, and the flask does not crack.
Flasks come in a variety of sizes: large, medium, small. Their openings can be closed with a rubber or peel plug. Sometimes there are marks on the flask: such
the flask is called a volumetric flask, and with its help liquids are measured. And some of the flasks have scions for the removal of the resulting gases. You can put on such an appendix
rubber tube and direct the gas to the desired location. Beakers are similar to ordinary beakers, and they are usually used to prepare solutions or conduct experiments. The glass has a spout on top to make it easier to pour the liquid. Glasses are made of glass and porcelain, of different sizes. Funnels are familiar to everyone, they also meet in the kitchen. The funnel comes in handy when you need to pour liquid into a container with a narrow neck. If you put a folded paper filter circle in the funnel, you can separate the liquid from the solid particles.
The vent tubes are made of glass and are inserted into the stopper. If you close a flask or test tube with such a stopper, where the reaction takes place and gas is released, then the gas will not fly into the air, but will go through the tube into the vessel where we will direct this tube. Such pipes have different shape... Sometimes it has not one, but several bends. You can bend the tube yourself. To do this, you need to heat the straight tube for some time in the flame of an alcohol lamp or a laboratory gas burner (not in the kitchen!) In the right place. When the glass becomes soft from the heat, you can bend the tube with a very slow and careful movement. But if you hurry, it will break. And be careful not to touch the hot part of the pipe with your fingers, or you will burn yourself. To cut a piece from a glass tube, you need to make a small scratch in the right place with a triangular file, and then gently break it in this place.
The porcelain steaming cup looks like a saucer with a spout. If you pour into it a solution of a substance, for example, table salt, and heat it for a long time, then soon all
the water will evaporate and the salt crystals will remain in the cup. This way you can isolate the substance from the solution.
The chemist needs a mortar and pestle. With their help, you can grind a solid into a fine powder that looks like flour. With such a powder, the experiment is faster than with large particles of the substance. And we also need a laboratory stand, in which we can fix the instruments as needed for the experiment. The tripod has a stable cast iron stand, and the stand is screwed into it. A clamp can be attached to the stand, into which a steel foot or ring is inserted and screwed. You can clamp a test tube or other device into the foot, and put an alcohol lamp or flask on a special grid on the ring. There are such tripods in the classrooms of both chemistry and physics at school, so you are probably familiar with them. This is not all that can be found in a chemical laboratory: there are so many different devices and utensils that it is difficult to list. The most interesting thing remains - to learn how to work with these devices.
A chemical laboratory can not only be composed purely of special chemistry kits, but also at home using household appliances, you can make a mini laboratory. In such a laboratory, you can perform some experiments and experiments, applying precautions: gloves, a dressing gown, an apron, a scarf or cap, safety glasses.
I will give a small list of experiments that any child of 13-18 years old can perform, but under the guidance of an adult, parents, teacher.
Litmus paper from red cabbage juice . ... To do this, you need red cabbage. Red cabbage juice when mixed with various substances changes its color from red (in strong acid), to pink, purple (this is its natural color in a neutral environment), blue, and finally green (in strong alkali). In the picture, from left to right, the results of mixing red cabbage juice with: 1. lemon juice (red liquid); 2. in the second test tube there is pure red cabbage juice, it has a purple color; 3. in the third test tube, cabbage juice is mixed with ammonia (ammonia) - a blue liquid is obtained; 4.in the fourth test tube, the result of mixing the juice withwashing powder - green liquid.
Below are the PH values for some fluids:
1. Gastric juice - 1.0-2.0 ph
2. Lemon juice - 2.0 ph
3. Food vinegar - 2.4 ph
4. Coca-Cola - 3.0 ph
5. Apple juice - 3.0 ph
6. Beer - 4.5 ph
7. Coffee - 5.0 ph
8. Shampoo - 5.5 ph
9. Tea - 5.5 ph
10. Saliva - 6.35-6.85 ph
11. Milk - 6.6-6.9 ph
12. Pure water - 7.0 ph
13. Blood - 7.36-7.44 ph
14. Sea water- 8.0 ph
15. Baking soda solution - 8.5 ph
16. Soap (fat) for hands - 9.0-10.00 ph
17. Ammonium alcohol - 11.5 ph
18. Bleach (bleach) - 12.5 ph
19. Caustic soda or sodium hydroxide> 13 ph
pH
Color
Red
purple
Violet
blue
blue-green
green-yellow
Red cabbage juice can be used to make litmus tests. For this you need filter paper. It must be soaked in cabbage juice and allowed to dry. Then cut into thin strips. Litmus papers are ready!
In order to memorize the color of litmus in different environments, there is a poem:
Litmus indicator - red
The acid will indicate clearly.
Litmus indicator - blue,
Alkaline is here - don't be silly
When is the neutral environment,
He is always purple.
Note: Not only red cabbage, but many other plants contain a PH sensitive plant pigment (anthocyanin). For example, beets, blackberries, black currants, blueberries, blueberries, cherries, dark grapes, etc. Anthocyanin gives plants a dark blue color. Foods of this color are considered to be very healthy.
Blue iodine
P 
Having done this experiment, you will see how a clear liquid turns dark blue in an instant. To experiment, you may need to go to the pharmacy for the necessary ingredients, but the miracle transformation is worth it.
You will need:
3 containers for liquid- 1 tablet (1000 mg) vitamin C (sold at the pharmacy)- solution of iodine alcohol 5% (sold in a pharmacy)- hydrogen peroxide 3% (sold in a pharmacy)- starch- measuring spoons- measuring cupsWork plan:1. Mash 1000 mg of vitamin C well with a spoon or mortar in a cup, turning the tablet into a powder. Add 60 ml warm water, mix thoroughly for at least 30 seconds. We will conventionally call the resulting liquid Solution A.2. Now pour 1 teaspoon (5 ml) of Solution A into another container, and also add to it: 60 ml of warm water and 5 ml of alcohol solution of iodine. Please note that brown iodine will become colorless when it reacts with vitamin C. Let's call the resulting liquid Solution B. By the way, we won't need Solution A anymore, you can put it aside.3. In a third cup, combine 60 ml of warm water, 1/2 teaspoon (2.5 ml) of starch, and one tablespoon (15 ml) of hydrogen peroxide. This will be Solution C.4. All preparations are now complete. You can call the audience and put on a show! Pour all of Solution B into the cup of Solution C. Pour the resulting liquid from one cup to the other and vice versa several times. A little patience and ... after a while the liquid will turn from colorless to dark blue.Explanation of experience:To explain to a preschooler the essence of the experience in a language understandable to him is as follows: iodine, reacting with starch, stains it in blue color... Vitamin C, on the other hand, tries to keep iodine colorless. In the struggle between starch and vitamin C, in the end, starch wins, and the liquid turns dark blue after a while.Pharaoh serpents
Preparatory part.
Put a tablet of dry fuel (urotropine) on the stand. Put three norsulfazole tablets on a dry fuel tablet. (Photo 1)
Main part.
Set fire to dry fuel. Use a metal rod to correct the crawling out shiny black light voluminous "snakes". After the end of the experiment, extinguish the fire by covering the dry fuel with a plastic lid. (Photo 2)
Due to the specific smell, this experiment is best performed in spacious, well-ventilated rooms or outdoors.
Explanation of experience.
The gases released during the decomposition of norsulfazole "foam" the reaction products, as a result a long black coal "snake" grows. Most likely decomposition products organic matter norsulfazole are - C, CO 2, H 2 O, SO 2 (possibly S), and N 2.
Spontaneous combustion of the fire
Preparatory part.
Place some crystalline potassium permanganate KMnO in a porcelain bowl 4
... Gently moisten the crystals with 1 ml of concentrated sulfuric acid H using a long pipette or glass tube 2 SO 4 ... Place the porcelain cup on a metal tray and disguise it,
placing wood shavings on top and around, making sure that no shavings get into the porcelain cup. (Photo 1)
Main part.
Imperceptibly for the audience, moisten a piece of cotton wool abundantly with alcohol and quickly squeeze a few drops of alcohol over a porcelain cup. (Photo 2)
Remove your hand immediately so that cotton wool with alcohol in your hand does not catch fire.
The fire flares up brightly and burns out quickly. (Photo 3)
Explanation of experience.
When concentrated sulfuric acid interacts with potassium permanganate, manganese (VII) oxide is formed, which is the strongest oxidizing agent. When alcohol comes into contact with manganese (VII) oxide, it ignites, then wood chips ignite.
Combustion of sodium in water
By 
preparatory part.
Carefully cut a pea-sized piece of sodium and place it in the center of the filter paper.
Pour water into a large porcelain cup. (Photo 1)
Main part.
Wasps 
Dip the sodium filter carefully into the water. We retreat to a safe distance (2 meters). Sodium, in contact with water, begins to melt, the evolved hydrogen quickly ignites, then sodium ignites and burns with a beautiful yellow flame. (Photo 2)
V 
At the end of the test, cracking and splashing usually occur, so it is dangerous to be near the porcelain cup.
If a drop of phenolphthalein indicator is added to the resulting solution (Photo 3), then the solution turns bright crimson, proving the formation of an alkaline medium. (Photo 4)
Explaining the experience
Sodium interacts with water according to the equation
2Na + 2H 2 O = 2NaOH + H 2
The paper filter does not allow sodium to "run" over the surface of the water, because of the generated heat, hydrogen ignites, and then sodium itself ignites, forming sodium peroxide.
2H 2 + O 2 = 2H 2 O
2Na + O 2 = Na 2 O 2
Trick with a scarf
By 
preparatory part.
Pour some crystalline phenolphthalein into the center of a white handkerchief.
Pour a solution of washing soda (sodium carbonate Na 2 CO 3). (Photo 1)
Main part.
Carefully cover the glass with a handkerchief so that the phenolphthalein spills into the glass unnoticed. (Photo 2) .Without removing the handkerchief, take the glass in your hand and make several circular motions to stir. (Photo 3) C 
take a handkerchief.
F 
the liquid in the glass turns crimson. (Photo 4)
Explanation of experience.
Sodium carbonate, when dissolved in water, undergoes hydrolysis, forming an alkaline medium.
Na 2 CO 3 + H 2 O = NaHCO 3 + NaOH
Phenolphthalein in an alkaline medium turns crimson.
R 
silver mirror action
Preparatory part.
In the first test tube, we prepare a glucose solution, for which we dissolve a quarter teaspoon of glucose in 5 ml of distilled water.
In the second test tube, prepare an ammonia solution of silver oxide: carefully add an ammonia solution to 2 ml of a silver nitrate solution, observing that the precipitate is completely dissolved in an excess of ammonia solution. (Photo 1)
Main part
We pour both solutions into a clean test tube. The cleaner the tube, the better the result!
Dip the test tube into a glass of hot water. We try to keep the test tube upright, do not shake it. (Photo 2).
After 2 minutes, a beautiful "silver mirror" is formed on the walls of the test tube. (Photo 3)
The silver test tube is a wonderful gift for young chemistry lovers.
(Photo 4)
Explanation of experience.
Glucose is an aldehyde alcohol. On the aldehyde group, it can be oxidized with an ammonia solution of silver oxide, forming gluconic acid. The silver is reduced and settles on the walls of the test tube, forming a "silver mirror".
2AgNO 3 + 2NH 3 + H 2 O = Аg 2 O? + 2NH 4 NO 3
Ag 2 O + 4NH 3 + H 2 O = 2OH
The reaction of obtaining a "silver mirror" is described by the equation:
2OH + C 6 H 12 O 6 = 2Ag? + C 6 H 12 O 7 + 4NH 3 + H 2 O
Getting oxygen from hydrogen peroxide
Preparatory part.
Pour 3% hydrogen peroxide solution into a conical flask. (Photo 1)
Main part.
We introduce into the flask a little catalyst - manganese (IV) oxide. (Photo 2) Oxygen immediately begins to evolve in the flask.
Z 
We light a long splinter and simmer it so that the splinter does not burn, but only smolders. (Photo 3)
We bring a smoldering splinter into the flask, it flares up and burns with a bright flame.
(Photo 4)
Explanation of experience.
When a catalyst (reaction accelerator) is added, hydrogen peroxide decomposes according to the equation:
2H 2 O 2 = 2H 2 O + O 2
When a smoldering torch is introduced, coal burns in oxygen according to the equation:
C + O 2 = CO 2
RULES FOR WORK IN A CHEMICAL LABORATORY
Before proceeding with the experiments, you need to prepare workplace, the necessary utensils and equipment, and carefully read the description of the experiment.
Experiments with chemical reagents pose an additional hazard. Difficult to remove stains, and even holes on clothes, can be left from various substances. Reagents can cause skin burns; especially you need to take care of your eyes. In addition, when mixing some completely harmless substances, the formation of poisonous compounds that can be poisoned is possible.
A reliable way to avoid unexpected troubles, undesirable reactions is to strictly follow the instructions, the description of the experience.
It must be remembered that substances cannot be tasted and taken by hand. And you need to get acquainted with the smell of substances with great care, with a slight movement of your hand directing the air from the vessel with the substance to the nose.
The liquid from the vessel must be taken with a pipette. Solids - spoon, spatula or dry test tube. Substances should not be stored together with food. Also, during the experiments, one should not take food.
The tube with the heated substance must not be directed towards your side or the side of someone who is standing next to you. Do not bend over the heated liquid, as splashes may get into the face or eyes.
After the end of the experiment, it is necessary to clean the workplace and wash the dishes. The substances remaining after the experiment should not be drained into the sewer or thrown into the trash bin.
Reagent bottles may have safety warning signs. These signs warn that one must be especially careful when handling solutions of acids and alkalis (these are caustic and irritating substances), flammable and poisonous substances.
RULES FOR HEATING SUBSTANCES
Heating of substances can be carried out using electric heating devices and an open flame. But in all cases, you must follow the safety rules.
Remember, the hottest part of the flame is the top. Its temperature is about 1200 C. Let us consider the device of an alcohol lamp, with the help of which it is possible to carry out heating. An alcohol lamp consists of a reservoir with alcohol, a tube with a disc, a wick and a cap.
Rice. 3. The device of the spirit lamp
HEATING SUBSTANCES IN A TEST TUBE
The tube is heated using a test tube holder. Before heating a substance in a test tube, it is necessary to warm up the entire test tube. The tube must be constantly moved in the flame of an alcohol lamp. You cannot boil liquid in a test tube.
HEATING LIQUID IN A FLASK
Liquids can be heated not only in test tubes, but also in flasks. It is forbidden to heat flasks made of thin-walled glass over an open fire without an asbestos mesh to avoid local overheating of the heated liquid. Let's give an example of heating water in a conical flat-bottomed flask. To do this, place the flask on a ring with an asbestos mesh, under which an alcohol lamp is located. The neck of the flask is fixed in the tripod leg. You can boil the liquid to be heated in the flask.
Rice. 4. Heating the liquid in the flask
Information technologies, including modern multimedia systems, can be used to support the active learning process. They have been attracting increased attention lately. An example of such training systems are virtual laboratories that can simulate the behavior of objects. the real world in a computer educational environment and help students acquire new knowledge and skills in the study of scientific and natural disciplines such as chemistry, physics and biology.
The main advantages of using virtual laboratories are:
Preparing students for a chemistry workshop in a real-world setting:
a) mastering the basic skills of working with the equipment;
b) training in the implementation of safety requirements in a safe environment of a virtual laboratory;
c) the development of observation, the ability to highlight the main thing, to determine the goals and objectives of the work, to plan the course of the experiment, to draw conclusions;
d) development of skills for finding an optimal solution, the ability to transfer a real problem to model conditions, and vice versa;
e) development of skills to formalize their work.
Conducting experiments that are not available in the school chemistry laboratory.
Remote practice and laboratory work, including work with children who have limited opportunities, and interaction with geographically distant schoolchildren.
Fast work performance, reagent economy.
Strengthening cognitive interest. It is noted that computer models of a chemical laboratory encourage students to experiment and get satisfaction from their own discoveries.
At the same time, it should be noted that the design and implementation of an educational information environment for active learning is a complex task that requires large time and financial costs, incomparable with the costs of creating an educational hypertext. Opponents of virtual chemical laboratories express well-founded fears that the student, due to his inexperience, will not be able to distinguish the virtual world from the real one, i.e. model objects created by a computer will completely replace the objects of the real world.
In order to avoid the possible negative effect of using model computer environments in the learning process, two main directions have been identified. First, when developing an educational resource, it is necessary to impose restrictions, to introduce appropriate comments, for example, to put them in the mouths of pedagogical agents. Second: use modern computer in school education in no way diminishes the leading role of the teacher. A creatively working teacher understands that computer technologies allow students to become aware of model objects, the conditions of their existence, better understand the material being studied and, which is especially important, contribute to the mental development of the student.
Various approaches can be used to create virtual laboratories. Virtual laboratories are divided according to the methods of delivery of educational content. Software products can be supplied on compact disks (CD-ROM) or placed on a site in the Internet, which imposes a number of restrictions on multimedia products. Obviously, 2D graphics are better suited for delivery over the Internet with its narrow communication channels. At the same time, in electronic editions supplied on CD-ROM, there is no need to save traffic and resources, and therefore three-dimensional graphics and animation can be used. It is important to understand that it is the volumetric resources - three-dimensional animation and video - that provide the highest quality and realism of visual information. According to the visualization method, laboratories are distinguished in which two-dimensional, three-dimensional graphics and animation are used. In addition, virtual laboratories are divided into two categories depending on the way knowledge about the subject area is presented. It is pointed out that virtual laboratories, in which the representation of knowledge about a subject area is based on individual facts, is limited to a set of pre-programmed experiments. This approach is used in the development of most modern virtual laboratories. Another approach allows students to conduct any experiment, not limited to a predetermined set of results. The virtual laboratory is one of the means of intensifying the process of teaching chemistry
In all spheres of education, they are looking for ways to intensify and quickly modernize the training system, improve the quality of education using computer technology... The possibilities of computer technologies as a tool of human activity and a fundamentally new means of teaching have led to the emergence of new methods.The main advantage of the approach is that the virtual laboratory desktop is visually presented as complete, albeit some organizational forms of training. simplified, image of a table in a real laboratory: chemical vessels and other devices are depicted in real proportions and arrangement (stands and holders are used), substances have a color corresponding to reality and the course of chemical reactions can be observed visually. Thus, the user gets an idea of \ u200b \ u200bworking in a real laboratory. A good example of such a lab is Crocodile Chemistry from Crocodile Clips Ltd, a firm specializing in the development of educational virtual computer labs. A part of the screen shot with chemical devices is shown in Fig. one.
The main disadvantage of this approach is the continuation of its main advantage - manual work with devices. This implies:
1) the impossibility of repeating the experiment several times, changing the conditions of the experiment, without manually repeating many of the same operations;
2) the impossibility of maintaining the sequence of operations, except with the help of a verbal description;
3) no room for error: if the test tube was accidentally overturned, then its contents will be irretrievably lost, there is no cancellation of actions in the known virtual chemical laboratories. It may seem that this is an advantage, the user learns to be more careful with chemical devices and reagents. However, this does not in any way affect the ability to handle real devices, but only interferes, since it distracts from the essence of the simulated process to control a computer program. The "Virtual Chemical Laboratory" includes a "Molecule Constructor" designed to build three-dimensional models of molecules of organic and inorganic compounds. The use of three-dimensional models of molecules and atoms to illustrate chemical phenomena provides an understanding of all three levels of representation of chemical knowledge: micro, macro and symbolic (Dori Y. et al., 2001). Understanding the behavior of substances and essence chemical reactions, becomes more conscious when it is possible to see the processes at the molecular level. The leading ideas of the paradigm of modern school chemistry education have been implemented: structure ® properties ® application.
Molecule Builder provides controlled, dynamic 3D color images of line, ball and scale models of molecules. Molecule Constructor provides the ability to visualize atomic orbitals and electronic effects, which significantly expands the scope of using molecular models in teaching chemistry.
Literature:
1.Batyshev S.Ya. "Professional pedagogy" M. 2003
2. Resurrection P.I. "Technique of laboratory work" ed. "Chemistry" 1970
3. Gurvich Ya.A. "Chemical Analysis" M. " graduate School"1989
4. Zhurin A.A. Chemistry assignments and exercises: Didactic materials for students in grades 8-9. - M .: School Press, 2004.
5. Konovalov V.N. "Safety precautions when working in chemistry" M. "Education" 1987.
6. Chitaeva O.B. "Work organization educational institution to update the content vocational training"M." Polygraph-S "2003
7. Encyclopedia for children. Volume 17. Chemistry / Chap. ed. by V.A. Volodin, led. scientific. ed. I. Leenson. - M .: Avanta +, 2003.
8. Yakuba Yu.A. “The relationship between theory and practice in educational process"M." High School "1998
The text of the work is placed without images and formulas.
Full version work is available in the tab "Files of work" in PDF format
Objective:
Obtaining a nanoobject in a school laboratory and researching its properties.
Tasks:
Find information in various sources about nanotechnology, its objects;
Collect information on the areas of application of these substances;
Get ferromagnets in a school laboratory, investigate their properties;
Draw conclusions based on the research carried out.
1. Introduction
Currently, few people know what nanotechnology is, although the future lies behind this science. More than 100 years ago, the famous physicist Max Planck first opened the door to the world of atoms and elementary particles. His quantum theory suggested that this sphere is subject to new, amazing laws.
2.1 What is hidden under the prefix "nano"
V last years in the headlines of newspapers and magazine articles, we increasingly come across words beginning with the prefix "nano". On radio and television almost every day we are informed about the prospects for the development of nanotechnology and the first results obtained. What does the word "nano" mean? It comes from the Latin nanus - "dwarf" and literally indicates the small size of the particles. Scientists have put a more precise meaning into the prefix "nano", namely one billionth part. For example, one nanometer is one billionth of a meter, or 0.0000000001m (10 -9m)
2.2 Nanotechnology as a science.
The increased interest of researchers in nanoobjects is caused by the discovery of unusual physical and chemical properties, which is associated with the manifestation of the so-called "quantum size effects". These effects are caused by the fact that with a decrease in size and a transition from a macroscopic body to a scale of several hundred or several thousand atoms, the density of states in the outer zone and in the conduction band changes sharply, which is reflected in the properties of electrons, primarily magnetic and electric, due to the behavior. The “continuous” density of states existing on the macroscale is replaced by separate levels, with the distances between them depending on the particle size. On such a scale, the material ceases to demonstrate the physical properties inherent in the macrostate of a substance or manifests them in an altered form. Due to this size-dependent behavior of physical properties and the non-typical nature of these properties in comparison with the properties of atoms on the one hand, and macroscopic bodies on the other, nanoparticles are isolated into a separate, intermediate region, and are often called "artificial atoms"
2.3 History of the development of nanotechnology
1905 year. Swiss physicist Albert Einstein published a paper in which he argued that the size of a sugar molecule is about 1 nanometer.
1931 year. German physicists Max Knoll and Ernst Ruska created an electron microscope, which made it possible for the first time to study nanoobjects.
1959 year. The American physicist Richard Feynman first published a paper that assessed the prospects for miniaturization.
1968 year. Alfred Cho and John Arthur, researchers at the American company Bell, developed the theoretical foundations of nanotechnology in surface treatment.
1974 year. Japanese physicist Norio Taniguchi introduced the word "nanotechnology" into scientific circulation, which he proposed to name mechanisms less than one micron in size. The Greek word for "drift" means roughly "old man."
1981 year. German physicists Gerd Binnig and Heinrich Rohrer created a microscope capable of showing individual atoms.
1985 year. American physicists Robert Curl, Harold Kroto and Richard Smaley have created technology that can accurately measure objects with a diameter of one nanometer.
1986 year. Nanotechnology has become known to the general public. American futurist Erk Drexler published a book in which he predicted that nanotechnology would soon begin to develop actively.
In 1959 nobel laureate Richard Feynman in his speech predicted that in the future, having learned to manipulate individual atoms, humanity will be able to synthesize anything. In 1981, the first instrument for manipulating atoms appeared - the tunnel microscope, invented by scientists at IBM. It turned out that with the help of this microscope one can not only "see" individual atoms, but also lift and move them. This demonstrated the fundamental possibility of manipulating atoms, and therefore, directly collecting from them, as if from bricks, anything: any object, any substance.
Nanotechnology is usually divided into three areas:
manufacturing of electronic circuits, the elements of which consist of several atoms;
the creation of nanomachines, that is, mechanisms and robots the size of a molecule;
direct manipulation of atoms and molecules and assembling anything from them.
In 1992, speaking before a commission of the United States Congress, Dr. Eric Drexler painted a picture of the foreseeable future when nanotechnology will transform our world. Hunger, disease, pollution will be eliminated environment and other pressing problems facing humanity.
2.4 Application.
Currently, magnetic fluids are actively studied in developed countries: Japan, France, Great Britain, Israel. Ferrofluids are used to create liquid sealing devices around rotating axles in hard drives. Ferrofluid is also used in many tweeters to remove heat from the voice coil.
Current Applications:
Thermal protection;
Optical protection (visible light and UV radiation);
Printer ink;
Media for recording information.
Perspective for 3-5 years:
Targeted drug transfer;
Gene therapy;
Nanocomposite materials for the automotive industry;
Lightweight and anti-corrosive nanocomposite materials;
Nanotechnology for production food products, cosmetics and other household items.
Long-term perspective:
Application of nanotechnology in the energy and fuel industries;
Environmental protection nanotechnology;
The use of nanotechnology for the manufacture of prostheses and artificial organs;
The use of nanoparticles in integrated nanoscale sensors;
Nanotechnology in space research;
Synthesis of nanomaterials in liquid non-aqueous media;
The use of nanoparticles for cleaning and disinfection.
3. Practical part
3.1 Laboratory experiment No. 1
Obtaining silver nanoparticles.
10 ml of distilled water was poured into a conical flask, adding 1 ml of 0.1 M silver nitrate solution and one drop of 1% tannin solution (it acts as a reducing agent). The solution was heated to boiling and a 1% sodium carbonate solution was added dropwise with stirring. An orange-yellow colloidal solution of silver is formed.
Reaction equation: FeCl 3 + K 4 Fe (CN) 6 K 3 Fe (CN) 6 + KCl.
3.2 Laboratory experiment No. 2
Obtaining nanoparticles of Prussian blue.
Poured into a flask 10 ml of distilled water and added 3 ml of 1% solution of yellow blood salt and 1 ml of 5% solution of iron (III) chloride. The blue precipitate that formed was filtered off. Part of it was transferred into a glass with distilled water, 1 ml of a 0.5% solution of oxalic acid was added to it, and the suspension was stirred with a glass rod until the precipitate was completely dissolved. A bright blue sol containing Prussian blue nanoparticles is formed.
3.3 Laboratory experiment No. 3
Let's get FMF in the laboratory.
We took oil (sunflower), as well as toner for a laser printer (substance in the form of a powder). Mix both ingredients until the consistency of sour cream.
In order to maximize the effect, heat the resulting mixture in a water bath for about half an hour, without forgetting to stir it.
Not every toner has strong magnetization, but only a two-component one - containing a developer. So you need to choose the highest quality.
3.4 Interaction of a magnetic fluid with a magnetic field.
The magnetic fluid interacts with the magnetic field in the following way: if you bring the magnet from the side, the fluid will climb up the wall and can rise as high as you like behind the magnet. By changing the direction of movement of the magnetic fluid, you can create a pattern on the wall of the vessel. The movement of a magnetic fluid in a magnetic field can also be observed on a glass slide. The magnetic fluid poured into the Petri dish swelled noticeably when the magnet was brought up, but did not become covered with thorns. We were able to reproduce only with a ready-made magnetic fluid MF-01 (manufacturer - OOO NPO Santon). For this, a thin layer of magnetic fluid was poured into a Petri dish and one magnet was brought to it, then several magnets. The liquid changes its shape, becoming covered with "thorns" resembling hedgehog thorns.
3.5 Tyndall effect
A little magnetic fluid was added to distilled water and the solution was thoroughly mixed. A beam of light from a laser pointer was passed through a glass with distilled water and through a glass with the resulting solution. The laser beam passes through the water without leaving a trace, and leaves a luminous path in the solution of the magnetic fluid. The basis for the appearance of the Tyndall cone is the scattering of light by colloidal particles, in this case, magnetite particles. If the particle size is less than the half-wavelength of the incident light, then diffraction light scattering is observed. Light bends around particles and scatters in the form of waves radiating in all directions. In colloidal systems, the particle size of the dispersed phase is 10-9 - 10-7 m, i.e. lies in the range from nanometers to fractions of micrometers. This region is larger than a typical small molecule but smaller than an object seen with a conventional optical microscope.
3.6 Making "magnetic" paper
They took pieces of filter paper, impregnated them with a magnetic fluid and dried them. Nanoparticles of the magnetic phase, filling the pores of the paper, gave it weak magnetic properties - the paper is directly attracted to the magnet. We managed to use a magnet to pull a figurine made of "magnetic" paper out of the glass through the glass.
3.7 Investigation of the behavior of magnetic fluid in ethanol
A small amount of the obtained magnetic fluid was added to ethyl alcohol. Mix thoroughly. The sedimentation rate of the magnetite particles was monitored. Magnetite particles settled in 2-3 minutes outside magnetic field... Magnetite, which has settled in ethanol, behaves interestingly - it moves compactly in the form of a clot after the magnet, leaving no trace on the wall of the test tube. Left in this position, it keeps it out of the magnetic field for a long time.
3.8 Experiments on removing contaminants from machine oil from water surfaces
A little machine oil was poured into the water, then a small amount of magnetic fluid was added. After thorough mixing, the mixture was allowed to settle. The magnetic fluid has dissolved in the engine oil. Under the influence of a magnetic field, a film of machine oil with a magnetic fluid dissolved in it begins to shrink to a magnet. The surface of the water is gradually cleared.
3.9 Comparison of the lubricating properties of engine oil and a mixture of engine oil with magnetic fluid
We placed engine oil and a mixture of engine oil with magnetic fluid in Petri dishes. Place a permanent magnet in each cup.
By tilting the cups, the magnets were moved and the speed of their movement was observed. In a cup of magnetic fluid, the magnet moved somewhat easier and faster than in a cup of machine oil. Individual nanoparticles containing no more than 1000 atoms are called clusters. The properties of such particles differ significantly from the properties of a crystal, which contains a huge number of atoms. This is due to the special role of the surface, because reactions with the participation of solids occur not in the volume, but on the surface.
4. Conclusion
A magnetic fluid (ferromagnetic fluid, ferrofluid) is a stable colloidal system consisting of nanosized ferromagnetic particles suspended in a carrier fluid, which is usually an organic solvent or water. By its properties, a ferromagnetic liquid resembles a "liquid metal" - it reacts to a magnetic field and is widely used in many industries. Thus, having studied the properties of a ferromagnetic liquid, we managed to obtain nanoobjects in a school laboratory.
5. References
Brook E. T., Fertman V. E. "Hedgehog" in a glass. Magnetic materials: from solid body to liquid. Minsk, Higher School, 1983.
Shtansky D.V., Levashov E.A. Multicomponent nanostructured thin films: problems and solutions. Izv. Universities. Non-ferrous metallurgy No. 3, 52 (2001).
http://teslacoil.ru/himiya/ferroflyuid/
http://khd2.narod.ru/technol/magliq.htm.
http://nanoarea.ru/index.php/dispersia-pokritia/140-obzor-primenenii
http://dic.academic.ru
http://magneticliquid.narod.ru/applications/011.htm
http://khd2.narod.ru/technol/magliq.htm
http://commons.wikimedia.org/wiki/File:Ferrofluid_Magnet_under_glass_edit.jpg?uselang=en
6.Application
6. Photos from experiments
The working program of the course of extracurricular activities "Laboratory of a young chemist" (grade 8. 35 h)
Planned results of mastering the course of extracurricular activities
Personal:
Formation of a holistic worldview corresponding to the modern level of development of science and social practice;
Formation of a responsible attitude to learning, readiness and ability for self-development and self-education, conscious construction of an individual educational trajectory, taking into account sustainable cognitive interests;
Formation of communicative competence in educational, teaching and research and creative activities;
Formation of cognitive and informational culture, skills independent work With teaching aids, books, available tools and technical means information technologies;
Formation of the foundations of environmental awareness and the need for a responsible, respectful attitude to your health and the environment;
Development of readiness for a solution creative tasks, the ability to find adequate ways of behavior and interaction with partners during training and outside learning activities, the ability to assess problem situations and promptly make responsible decisions in various productive activities.
Metasubject:
Mastering the skills of independent acquisition of new knowledge, organization of educational activities, search for means of its implementation;
The ability to plan ways to achieve goals on the basis of an independent analysis of the conditions and means of achieving them, to highlight alternative ways to achieve the goal and choose the most effective way, to carry out cognitive reflection in relation to actions to solve educational and cognitive tasks;
Ability to understand a problem, pose questions, put forward a hypothesis, define concepts, classify, structure material, conduct experiments, argue one's own position, formulate conclusions and conclusions;
Ability to correlate their actions with the planned results, to monitor their activities in the process of achieving a result, to determine the methods of action within the framework of the proposed conditions and requirements, to adjust their actions in accordance with the changing situation;
Building and developing competence in the use of tools and technical means information technology (computers and software) as an instrumental basis for the development of communicative and cognitive universal educational actions;
Ability to create, apply and transform signs and symbols, models and schemes for solving educational and cognitive tasks;
Ability to extract information from various sources (including mass media, educational CDs, Internet resources), freely use reference literature, including electronic media, comply with the standards of information selectivity, ethics;
Ability in practice to use basic logical techniques, methods of observation, modeling, explanation, problem solving, forecasting, etc.;
Ability to work in a group - to effectively cooperate and interact based on the coordination of various positions in the development of a common solution in joint activities; listen to your partner, formulate and argue your opinion, correctly defend your position and coordinate it from the position of partners, including in a situation of conflict of interests; efficiently resolve conflicts based on taking into account the interests and positions of all its participants, searching for and evaluating alternative ways of resolving conflicts.
Subject:
In the cognitive sphere:
- give definitions of the learned concepts;
- describe demonstration and self-conducted chemical experiments;
- describe and distinguish the studied substances used in everyday life;
- classify the studied objects and phenomena;
- draw conclusions and inferences from observations;
- structure the studied material and chemical information obtained from other sources;
- safe handling of substances used in everyday life.
In the value-orientational sphere:
analyze and assess the environmental consequences of human household and industrial activities associated with the use of chemicals.
In the labor sphere:
conduct a chemical experiment.
In the field of life safety:
comply with the rules for the safe handling of substances and laboratory equipment.
Introduction. Fundamentals of Safe Handling of Substances (1 hour).Goals and objectives of the course.
Section 1. In the laboratory of amazing transformations (13 h).
Practical work.1. Obtaining soap by alkaline saponification of fats. 2. Preparation of solutions of a certain concentration. 3. Growing salt crystals.
Section 2. In the laboratory of a young researcher (11 hours).Experiments with natural objects (water, soil).
Practical work.4. Study of the properties of natural water. 5. Determination of the hardness of natural water by titration. 6. Analysis of the soil. 7. Analysis of snow cover.
Experiments with food.
Practical work.8. Investigation of the properties of carbonated drinks. 9. Research of the qualitative composition of ice cream. 10. Research on the properties of chocolate. 11. Research of chips. 12. Investigation of the properties of chewing gum. 13. Determination of vitamin C in fruit juices and nectars. 14. Investigation of the properties of black tea bags.
Section 3. In the creative laboratory.
Training time reserve - 4 hours
The name of the program | Working program of the course of extracurricular activities "Laboratory of a young chemist". Compiled by L.V. Chernogorova, chemistry teacher at MBOU Secondary School No. 31, Lipetsk |
||||
Number of hours per year | |||||
Number of hours per week | |||||
Number of backup hours | |||||
Classes | |||||
Teacher | Chernogorova Larisa Viktorovna |
||||
Quarter, a week | lesson I know | lesson in the subject | Course topic, lesson topic | Planning correction |
|
Introduction. Fundamentals of Safe Handling of Substances. (1 h) | |||||
I quarter | Goals and objectives of the course.Acquaintance with the content of the course and the requirements for organizing and conducting classes. Rules for safe work with chemicals and laboratory equipment. Fire safety rules. | ||||
Section 1. In the laboratory of amazing transformations. (13 h) |
|||||
Entertaining experiments with substances used in everyday life ("Chemical algae", "Chemical jellyfish", "Fireproof handkerchief", "Fireproof thread", etc.). | |||||
Practical work.1. Obtaining soap by alkaline saponification of fats. | |||||
Entertaining experiments with medicinal substances ("Pharaoh's snakes", experiments using iodine, green tea, potassium permanganate, alcohol, boric acid, acetylsalicylic acid, hydrogen peroxide, etc.). | |||||
Entertaining experiments with gases ("Diving egg", "Smoke without fire", "Explosive gas explosion", "Ammonia fountain", etc.). | |||||
Experiments with solutions ("Orange - lemon - apple", "Getting milk, wine, soda", "Blood without a wound", "Chemical rainbow", etc.). | |||||
Practical work 2. Preparation of solutions of a certain concentration. | |||||
Reserve | |||||
II quarter | Entertaining experiments with acids ("Chemical Snow", "Carbonization of Sugar", "Fireworks in a Cylinder", "Mysterious Ink", etc.). | ||||
Experiments with salts ("Winter Landscape in a Glass", "Golden Rain", "Golden Autumn", "Silver Flower", "Chemical Trees", "Tin Soldier", etc.). | |||||
Practical work 3. Growing salt crystals. | |||||
Entertaining experiments with the presence of fire ("Spontaneous combustion of a candle, campfire", "Magic wand", "Chemical fireflies", "Burning sugar", "Volcanoes on the table", "Chemical fireworks", "Death of a squadron", "Water is an arsonist" and etc.). | |||||
Reserve | |||||
Section 2. In the laboratory of a young researcher. (11 h) |
|||||
III quarter | Practical work 4. Study of the properties of natural water. | ||||
Practical work 5 ... Determination of the hardness of natural water by titration. | |||||
Practical work 6. Analysis of the soil. | |||||
Practical work 7 ... Snow cover analysis. | |||||
Practical work 8 ... Study of the properties of carbonated drinks. | |||||
Practical work 9. Study of the qualitative composition of ice cream. | |||||
Practical work 10. Research on the properties of chocolate. | |||||
Practical work 11 ... Chips research. | |||||
Practical work 12 ... Investigation of the properties of chewing gum. | |||||
Reserve | |||||
Reserve | |||||
IV quarter | Practical work 13. Determination of vitamin C in fruit juices and nectars. | ||||
Practical work 14. Investigation of the properties of black tea bags. | |||||
Section 3. In the creative laboratory (6 hours). |
|||||
Creative report. Registration of research results in the form of research work, presentation of works at a scientific and practical conference. Script writing extracurricular activities using entertaining chemical experiments. | |||||
