Various materials to help a school chemistry teacher
- Fun challenges for chemistry lessons
- Lesson. Essential chemical concepts
- Innovative model of work of the Republican Educational Institution of Chemistry and Biology “Increasing the professional competence of a chemistry and biology teacher in the context of updating the content of education”
- Certification: Chemistry Teacher Portfolio
- Brochure. Russian vocabulary in chemical terminology
- Specifics of a monologue-speech at a scientific-practical conference
- Report on the work done in chemistry, biology and ecology
- Educational program of the chemical-ecological circle
- Master class: “Organization of student research activities”
- The use of active forms of learning for the development of student cognitive competencies in the context of the implementation of the Federal State Educational Standard for basic general education
Research papers in chemistry
- Research work “The influence of energy drinks on the human body”
- Research work “Study of iodine content in the body of students and the food they consume”
- Study “Determination of lycopene in tomato products”
- Research work “Table salt and its properties”
- Research work “pH of cosmetics”
- Research paper "The Great and Terrible Bisphenol-A"
- Research work “Study of the physical and chemical composition of water at the site of the Sterlitamak meteorite fall”
Chemistry Presentations
- Chemistry presentation: Experiment with flowers
- Presentation: White magic lesson
- Presentation: Combustion of magnesium in carbon dioxide
- Chemistry Presentation: Nomenclature of Alkanes
- Presentation: Theory of chemical structure by A.M. Butlerov
- Why is chemistry needed?
- Presentation: The effect of energy drinks on the human body
- Presentation on chemistry “Isomerism and its types”
- Presentation: “Technology of problem-based dialogue learning”
- The self-presentation “Let me introduce you” will be of interest to those chemistry teachers who will participate in the “Teacher of the Year” competition
- Presentation: “Requirements for a modern lesson in the context of the implementation of the Federal State Educational Standard”
- Presentation on chemistry “Fascinating experiments”
- Chemistry presentation “Tips for a research director”
Work programs in chemistry
- Working programm. Chemistry. 9th grade.
- Working programm. Chemistry. Grade 11. Profile level.
- Working programm. Chemistry. Grade 10. A basic level of.
- Working programm. Chemistry. Introductory course. 7th grade.
- Diagnostic work in chemistry, grade 11.
- Diagnostic work in chemistry, grade 8.
Works: All Selected To help the teacher Competition “Educational Project” Academic year: All 2015 / 2016 2014 / 2015 2013 / 2014 2012 / 2013 2011 / 2012 2010 / 2011 2009 / 2010 2008 / 2009 2007 / 2008 2006 / 2007 2005 / 2006 Sorting: Alphabetically Newest
How did Nobel Prize Winners from Great Britain and Russia contribute to the progress of Humanity
The history of the Nobel Prize and its creator. British Nobel laureates. Russian Nobel laureates. The influence of the Nobel Prize on the progress of mankind.
"Quindecim miracula" Amur region
Project goal: to reveal the concept of “quindecim miracula” of the Amur region; characterize the existing mineral springs of the Amur region, study their chemical composition and effect on the human body.
And our water is a particle of health, or...
A study on a comprehensive hygienic assessment of the quality of drinking water from various sources on the territory of the Rozhdestvenskoe rural settlement is described. 12 samples of well and tap water were studied using visual-colorimetric, organoleptic methods (A.G. Muravyov’s method), and the titration method. Recommendations for improving water quality are proposed.
Highway, snow, soil, plants
The work clarifies the influence of the highway on the content of lead and chlorine ions in snow, soil and plants. The negative impact of high concentrations of these ions on living organisms has been proven.
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Recently, the car has become a human competitor in the struggle for living space. Object of study: the problem of environmental pollution by motor vehicles and its prevention in modern society. In the course of the work, the level of atmospheric pollution in the Kuznetsk district of Novokuznetsk by vehicle exhaust emissions was studied. Measures have also been developed to protect the environment from the influence of motor vehicles.
Automotive fuel and its application
This work shows the interdisciplinary connection of chemistry with the professional cycle of subjects in the profession of “Auto mechanic”. The work describes the main types of automobile fuel, its areas of application, and the processes occurring during fuel combustion.
Agent 000, or Shield and Sword
Everyone knows the role of ozone for planet Earth: the ozone shield protects all living things from aggressive ultraviolet radiation. But ozone is also a sword. The famous James Bond was agent 007, the zeros before the seven meant that the agent had the right to kill. The code designation for ozone is even more menacing - three zeros, 000. Ozone is an agent with the right to mass kill bacteria and all kinds of harmful impurities. The purpose of the work is to study the properties of ozone and search for reagents for its detection. The discovery of ozone is described; the role of the Earth's ozone layer; Ozone workers professions. In the experimental part of the work, ozone was obtained physically - using a continuous spark discharge; chemical method - acting with concentrated sulfuric acid on potassium peroxosulfate. The bleaching effects of ozone on dyes were studied. We selected a more sensitive reagent for detecting ozone - a mixture of solutions of ferrous sulfate and potassium thiocyanate.
Agronomy. Effect of mineral fertilizers
The work provides information on the history of agronomy. The characteristics of macro- and microfertilizers, their biological role for the growth and development of plants are given. Particular attention is paid to nitrates in terms of the consequences of their use by humans.
Agrochemical study of the soil at the school site of the "Zhasyl Alan" school
The work examines the issues of soil fertility and carries out a quantitative analysis of the content of sulfate, carbonate and chloride ions from a sample of a school plot of land. A bacteriological analysis was also carried out jointly with the regional veterinary laboratory and the amount of nitrates and pH of the soil was determined together with the regional sanitary and epidemiological station.
Agrochemistry for eighth graders
I was assigned the following tasks: to determine the physical and chemical state of the soil from a summer cottage, to conduct a comparative analysis of the growth of indoor plants and vegetable crops on the studied soil with and without mineral fertilizers, to use industrial nitrogen-containing wastewater from the NPK production (Rososh) as a mineral fertilizer ). Based on the results of my research, it can be argued that fertilizers are a stimulator of plant growth, but only in the doses it needs.
Adsorption of acetic acid by activated carbon
The purpose of our work was to study the adsorption of acetic acid and select a process model (Langmuir and Freundlich adsorption models). By experimentally determining the difference between the solution concentration before and after adsorption for solutions of different concentrations and knowing the mass of the adsorbent, we obtained data on specific adsorption depending on the equilibrium concentration of the solution.
Nitrogen in food, water and the human body
The work provides information about the role of nitrogen for the human body, water, and air. Methods for determining (detection) fixed nitrogen in various substances: food, water, air are described. Food products (flour, starch, cheese, bread, water, etc.) and air were analyzed for the presence of nitrogen in them. The importance of protein foods for humans is shown. The dangers of fashionable protein diets are assessed.
Nitrogen and its compounds
The work examines the structure, properties and use of nitrogen and its compounds; shows the importance of nitrogen, its effect on living organisms; nitrogen cycle in nature; Diagrams for the production of nitrogen fertilizers and their use in crop rotation are presented.
Nitrogen as a biogenic element
The work is devoted to the study of the biological role of nitrogen. It examines the significance of the most important compounds of this element, as well as its relationship with legumes. The material contains interesting information about the freezing of living structures in liquid nitrogen.
Let's look around. The nature around us is filled with many beautiful rich colors. So I decided to borrow a piece of this variety of colors from her. The work describes the types of paints and the history of their invention; method of making watercolor paints. A method is described for extracting dyes from various plants and preparing paints from them suitable for painting.
Watercolor paints. Their composition and production
The work is devoted to research into the physical and chemical properties of watercolor paints. The properties and features of paints are considered. The characteristics of the main components of watercolor are given. The issue of industrial production of watercolor paints is touched upon. A description of the method for extracting dyes from plants is given. A technique for obtaining a base for watercolor paints based on available raw materials is presented.
Aquarium as a chemical and biological research object
Many novice aquarists dream of having fish such as labeo in their aquariums, not knowing that the water in them does not always correspond to the natural habitat conditions of these fish. This project outlines simple and accessible methods for studying the physical and chemical parameters of aquarium water.
Activated carbon. Adsorption phenomenon
“Adsorption” (from the Latin “ad” - on, with, and “sorbeo” - absorb) is the absorption of any substance (adsorbate) from a gaseous medium or solution by a surface layer of a liquid or solid (adsorbent). Adsorption plays an important role in many natural processes. It is thanks to adsorption that the first stage of absorption of various substances from the environment by cells and tissues of biological systems occurs. The work investigated the adsorption capacity of activated carbon. The application of this property in practice is shown.
Actinoids: a look from the past to the future
The work presents data on the family of actinide elements (No. 89-103 PSHE): general characteristics of the element, history of discovery, preparation. A separate chapter provides information about nuclear fuel, its classification, and the design of nuclear reactors.
The relevance of the pedagogical views of D.I. Mendeleev in the light of modernization of modern Russian education
The work analyzes the works of D.I. Mendeleev on problems of education. The purpose of the work is to compare the tasks of modernizing Russian education, the requirements of the Federal component of the State Standard of General Education and the views of D.I. Mendeleev on the development of education in Russia and substantiation of the relevance of these views today.
Our actions:
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Figure 3 |
Figure 4 |
Our actions:
1. Pour milk into a container.
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Figure 4 |
Figure 5 Figure 6 |
Our actions:
1. Inflate a balloon.
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Figure 10 |
Figure 11 |
1 experience.
Our actions:
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Figure 14 |
Figure 15 |
Our actions:
Figure 16 Figure 17
Figure 18 Figure 19
Figure 20 Figure 21
View document contents
"Chemistry in the kitchen"
Orenburg region
Orenburg district
Chernorechye village
1.Introduction……………………………………………………………………… 3
2. Main part………………………………………………………4
2.1 Cooking and chemistry………………………………………………………. 4
1.Chemistry and substances………………………………………………………. 4
2. Chemical reagents in the kitchen …………………………………………. 5
2.2. Experiments in the kitchen………………………………………………………. 6
1.Experiment with vinegar and soda……………………………………………………6
2.Experiment with milk and paints……………………………………………………………….. 6
3. experiment with milk writing and heating……………………………………………………… 6
4.Experiment with sunflower oil…………………………………………………………….6-7
5. Plastic from milk……………………………………………………… 7
3. Conclusion………………………………………………………………………………. 8
4. List of references………………………………………………………. 9
5. Appendix………………………………………………………….10-12
1. Introduction
I really like helping and watching mom when she cooks in the kitchen. One day, while my mother was preparing breakfast, I saw her adding something sizzling and bubbling to the pancake batter. At that moment, mom looked like a sorceress. I asked: “What is this and why are you putting it in the dough?” Mom smiled and replied that the kitchen is a small chemical laboratory.
I read what “chemistry” is in the encyclopedia. In the photographs I saw different test tubes and jars. But what is the connection between delicious pancakes and chemicals and transformations? This is what I decided to find out, and my mother happily agreed to help me with this. When my mother and I thought about the products in the kitchen, it turned out that the kitchen is nothing more than a chemical laboratory. And the products themselves are chemicals.
Thus was born a project on the topic "Chemistry in the kitchen".
Object Our research included products and substances that mother uses for cooking.
Subject is
We have set ourselves target
To achieve our goal, we decided to go through the decision adach:
1. Find out what chemistry and chemical substances are.
Hypothesis: 1.I assumed that the kitchen is a chemical laboratory.
2. I admitted that it is possible to prove through experiments that interesting chemical experiments take place in our kitchen every day.
2.Main part 2.1.Cooking and chemistry
1 Chemistry and substances
Chemistry - one of the sciences about nature, about the changes occurring in it. The subject of the study of chemistry is substances, their properties, transformations and processes accompanying these transformations.
There are a huge amount of useful and harmful substances around us! For example, in nature there are natural substances, that is, those that were created without human intervention. These are water, oxygen, carbon dioxide, stone, wood and others.
Although I haven't studied chemistry in school yet, I already know about such a common element in nature as water. This substance can surprisingly have three states - liquid, solid, gaseous.
It was in the kitchen that I traced all her states.
If you boil water, it turns into hot steam - gas.
If you freeze water in the freezer, the water turns into ice. In this case, ice takes up more volume than water. Therefore, to prevent the bottle from bursting in the freezer, mom does not fill the water completely, leaving extra space in the bottle. Understanding countless useful and harmful substances, learning their structure, properties, and role in nature is one of the tasks of chemistry. All people need it - the builder, the farmer, the doctor, the housewife and the cook.
Chemistry has existed since ancient times, but it became a real science quite recently - no more than 200 years ago. The theoretical foundations of chemistry were laid by the ancient Greek scientists Anaxagoras and Democritus. The creators of the modern system of ideas about the structure of matter are considered to be: the great Russian scientist M.V. Lomonosov, French chemist A. Lavoisier, English physicist and chemist J. Dalton, Italian physicist A. Avogadro.
2 Chemical reagents in the kitchen
Since I learned that chemistry is the science of matter, it would be reasonable to assume that there are many different substances in the kitchen. And when preparing various dishes, chemical reactions probably occur.
I wonder how a kitchen resembles a science laboratory?
Let's open the kitchen cabinet. Vinegar, baking soda, vegetable oil, sugar, flour, salt, milk, starch.
There is nothing chemical here, you say. Regular food.
But it was not there! These are real chemicals with the help of which tasty, nutritious and healthy dishes appear on our table. These substances even have chemical names.
vinegar - acetic acid;
sugar - sucrose;
starch is a polysaccharide,
milk - lactose;
Total chemistry!
It's time to conduct a series of chemical experiments in the kitchen.
I intend to conduct all experiments with the help of my mother.
2.2. Experiments in the kitchen
1 Experiment with vinegar and soda “Vulcan”
Baking soda is sodium bicarbonate NaHCO3.
Vinegar is a colorless liquid with a sharply sour taste and aroma. It contains acetic acid.
When they are mixed, a chemical reaction occurs - carbon dioxide and water are released. This can be seen from experience - the mixture bubbles and begins to increase in volume. Therefore, the so-called lava of a volcano is obtained.
Application
1. This property of vinegar and soda is used very often in the kitchen when making baked goods - pies, buns and other dough dishes. This reaction is called “quenching soda.” When carbon dioxide is released, it saturates the dough and the baked goods become airy and porous.
The most important thing when using soda is to bake the dough immediately, since the chemical reaction takes place very quickly. You can also quench soda with fermented milk products (for example, kefir) - if they are part of the dough, then it is not necessary to add vinegar.
Milk is a liquid that contains various substances, including fat. The detergent attacks the fat in the milk and a chemical reaction occurs between the fat and the BIOLAN detergent.
A chemical reaction is the process of mixing different substances, as a result of which new substances are formed, while they become a different color, or a gas is released, or energy is released.
In our case, energy has been released that moves the paints. ( For a description of the experience, see the appendix)
Milk contains water and other substances such as the protein casein. When we ironed the sheet of paper with an iron, we heated the milk to a temperature of +100 °C. After this, the water evaporated, and the casein protein fried and turned brown. For a description of the experience, see the appendix.
4 Experience with sunflower oil
Sunflower oil is oil made from sunflower seeds. It is often used in the kitchen for frying, salad dressing, and baking.
It has interesting properties.
First we conducted an experiment with a balloon.
This experiment showed that the oil spread around the edges of the hole in the balloon and did not let air out, so the balloon did not deflate.
A little secret - it was possible to pierce the ball only in places where it was not under strong tension, that is, where it was softer (at the very top and next to the knot). The rubber stretched, and then contracted and, with the help of oil, no longer allowed air to pass through. The skewer was slowly pushed and turned, and it easily entered between the rubber molecules, which were connected in long chains. This experience showed more physical properties of oil and rubber.
It does not sink in water and does not mix with it. For a description of the experience, see the appendix.
5 Experience in producing plastic from milk
Plastic consists of long molecules, which gives it flexibility. Milk contains the protein casein; its long molecules are suitable for plastic production. For a description of the experience, see the appendix.
4. Conclusion
Having studied the literature and carried out experiments, we were convinced that many of the processes occurring in our kitchen are chemical phenomena.
So my hypothesis was confirmed - the kitchen is a chemical laboratory.
5 Literature
1. The program “NEOKuhnya” on the “Carousel” channel, directed by Alexander Dashko.
2.www.alhimik.ru/teleclass/azbuka/1gl.shtml - electronic version of the chemical alphabet from the newspaper "Chemistry" of the publishing house "First of September".
3.N.M. Zubkova "Scientific answers to children's "whys". Experiments and experiments for children from 5 to 9 years old." Publishing house Rech 2013
4. Olgin O. Let's do some chemistry!: Entertaining experiments in chemistry / Ill. E. Andreeva. – M.: Det. Lit., 2002. – 175 pp.: ill. – (Know and be able to!).
Application
1. Experiment with Vulcan vinegar and soda.
Our actions:
1. Cut off the neck of a plastic bottle - this is the base of the volcano.
2. Plasticine was put on the bottom of the neck and placed on a large plate.
3. Pour 2 tbsp inside the bottle. l of soda and added red paint to make the volcano beautiful.
4. While the volcano is sleeping (Figure 1).
5. Pour water mixed with vinegar in a ratio of 4:1 (4 parts water and 1 part vinegar) into the neck of the bottle.
6. A chemical reaction has begun between baking soda and vinegar. The volcano began to erupt with red lava (Figure 2).
| Picture 1 | Figure 2 |
Our actions:
3. Take a cotton swab and soak it in dishwashing liquid.
4. Dip this cotton swab into a container with milk and paints (Figure 3).
5. As a result, the paints “ran away” from the cotton swab to the sides. While you hold the stick in the milk, the colors constantly spread from it in different directions, you get very beautiful swirls and patterns (Figure 4)
|
Figure 3 |
Figure 4 |
Our actions:
1. Pour milk into a container.
2. Take a sheet of paper and a brush.
3. We soaked the brush in milk and began to write on paper with “milk ink” (Figure 4)
4. The result was invisible writing on paper.
5. Let the milk dry for 10 minutes.
6. Ironed a sheet of paper with milk notes. (Figure 5)
7. As a result, a brown phrase appeared. In our case - “Chemistry in the kitchen” (Figure 6).
|
Figure 4 |
Figure 5 Figure 6 |
Our actions:
1. Inflate a balloon.
2. Take a long narrow wooden stick (skewer) and soak it completely in sunflower oil (Figure 10).
3. Slowly pierce the ball right through with this stick. The balloon didn't burst! (Figure 11)
|
Figure 10 |
Figure 11 |
1 experience.
Our actions:
1. Pour oil into a transparent glass.
2. Using a syringe, drop water tinted with green gouache into the oil.
3. There were droplets of green water in the oil, which did not mix with the oil but simply floated in the glass (Figure 14).
4. We dropped a fizzy tablet into the oil and the reaction of carbon dioxide release began, the bubbles of which began to move the “balls” of green water and lift them to the top (Figure 15).
It was one of the most beautiful experiences of the project!
|
Figure 14 |
Figure 15 |
5. Experience in producing plastic from milk.
For the experiment we will need: milk, vinegar, a small saucepan, a mold.
Our actions:
1. Heat the milk in a saucepan so that it is warm, but does not boil or foam (Figure 16).
2.Remove from the stove and add a few drops of vinegar (Fig. 17).
3. The resulting mass is similar to liquid rubber (Fig. 18).
4. We carefully wash this mass under running water (Fig. 19).
5. Pour it into the molds. (Fig. 20) We wait three days.
6. The plastic is ready (Fig. 21).
Figure 16 Figure 17
R 
Figure 18 Figure 19
Figure 20 Figure 21
View document contents
"TITLE PAGE "
Orenburg region
Orenburg district
Municipal budgetary educational institution
"Chernorechensk secondary school named after the holder of the Order of the Red Star A.I. Gonyshev"
Chernorechye village
View document contents
"protection"
Hello! I, Daria Plotnikova, a 3rd grade student at the School named after Alexander Ivanovich Gonyshev
| Allow me to introduce my research work “Chemistry in the Kitchen”. |
|
| I really like helping and watching mom when she cooks in the kitchen. One day, while my mother was preparing breakfast, I saw her adding something sizzling and bubbling to the pancake batter. At that moment, mom looked like a sorceress. I asked: “What is this and why are you putting it in the dough?” Mom smiled and replied that the kitchen is a small chemical laboratory. This is what I decided to find out, and my mother happily agreed to help me with this. When my mother and I thought about all the products in the kitchen, it turned out that the kitchen is nothing more than a chemical laboratory. And the products themselves are chemical substances with their own properties and characteristics. This is how the project was born topic"Chemistry in the kitchen" . |
|
| Object Research began on the products and substances that mom uses for cooking. |
|
| The subject is study of phenomena occurring with substances and products in the kitchen. |
|
| Purpose of the study : find out how our kitchen is similar to a chemical laboratory. |
|
| To achieve the goal it was supposed to solve the following problems adachi: Learn what chemistry and chemical substances are. Conduct chemical experiments with edible products. Prove that the kitchen is a whole chemical laboratory |
|
| Hypothesis: 1. We assumed that the kitchen is a chemical laboratory, that with the help of experiments it can be proven that entertaining chemical experiments take place in our kitchen every day. Let's try to prove it. |
|
| There are a huge amount of useful and harmful substances around us! For example, in nature there are natural substances that were created without human intervention. These are water, oxygen, carbon dioxide, stone and others. There are substances created by man. They are called artificial substances. These are plastic, rubber, glass and others. Any substance can be either in its pure form or consists of a mixture of pure substances. Due to chemical reactions, substances can be transformed into a new substance. I'm not studying chemistry yet, but I can already say that water comes in three states. It was in the kitchen that I traced this. If you boil water, it turns into hot steam - gas. If you freeze water in the freezer, the water turns into ice. Understanding useful and harmful substances, learning their structure, properties, and role in nature is one of the tasks of chemistry. Since I learned that chemistry is the science of matter, it would be reasonable to assume that there are many different substances in the kitchen. And when preparing various dishes, chemical reactions probably occur. I wonder how a kitchen resembles a science laboratory? |
|
| Let's open the kitchen cabinet. Vinegar, baking soda, vegetable oil, sugar, flour, salt, milk, starch. Nothing chemical, you say, not here. Regular food. But it was not there! These are real chemicals with the help of which tasty, nutritious and healthy dishes appear on our table. These substances even have chemical names. For example: salt is sodium chloride; baking soda - sodium bicarbonate; vinegar - acetic acid; sugar - sucrose; starch is a polysaccharide, milk is lactose. Total chemistry! |
|
| It's time to conduct a series of chemical experiments in the kitchen. My mother helped me in conducting the experiments. |
|
| Experiment with vinegar and soda "Vulcan". Pour 2 tbsp inside the bottle. l of soda and added red paint to make the volcano beautiful. Next, pour water mixed with vinegar in a 4:1 ratio (4 parts water and 1 part vinegar) into the neck of the bottle. A chemical reaction began between baking soda and vinegar. The volcano began to erupt with red lava |
|
| . Pour milk into the container. We add three types of paints - red, blue, green. The result was beautiful patterns in the milk. Take a cotton swab and soak it in dishwashing liquid. We dip this cotton swab into a container with milk and paints. As a result, the paints “ran away” from the cotton swab to the sides. While we hold the stick in the milk, the colors constantly spread from it in different directions, creating very beautiful patterns. |
|
| Pour milk into a container. Take a sheet of paper and a brush. We wet the brush in milk and write on the paper with “milk ink”. The result was invisible inscriptions on paper. Let the milk dry for 10 minutes and iron the sheet of paper with the milk notes. As a result, a brown phrase appeared. In our case - “CHEMISTRY IN THE KITCHEN” |
|
| Experience with sunflower oil. Inflate the balloon and take a long narrow wooden stick (skewer) and soak it completely in sunflower oil. Slowly pierce the ball right through with this stick. The balloon didn't burst! |
|
| Pour oil into a transparent glass and use a syringe to drop water tinted with green gouache into the oil. There were droplets of green water in the oil, which did not mix with the oil, but simply floated in the glass. We put a tablet of fizz into the oil, the reaction of carbon dioxide release began, the bubbles of which began to move the “balls” of green water and lift them to the top. It was one of the most beautiful experiences of the project! |
|
| Experience in producing plastic from milk. For the next experiment we will need: milk, vinegar, a small saucepan, a mold. Heat the milk in a saucepan until it is warm, but not boiling or foaming. Remove from heat and add a few drops of vinegar. The resulting mass is similar to liquid rubber. We carefully wash this mixture under running water. Pour it into molds. We wait three days. The plastic is ready. |
|
| Having studied the literature, done experiments, we were convinced that many of the processes occurring in our kitchen are chemical phenomena. |
|
| So my hypothesis confirmed - kitchen - chemical laboratory .. To master all the subtleties of the art of cooking, you need to know a lot. A real culinary specialist must be a person educated in the field of chemistry, biology, biochemistry, and nutritional physiology. During this project, we were able to complete the assigned tasks. We learned what chemistry and chemical substances are, and conducted chemical experiments with different products. Thus, we proved that the kitchen is a whole chemical laboratory. |
|
| Thank you for your attention! |
View presentation content
“Plotnikova Daria. presentation of work"
Performed:
3rd grade student
MBOU "School named after A.I. Gonyshev"
Plotnikova, Daria
Head of work:
Gonysheva Svetlana Vladimirovna
primary school teacher
An object:
products and substances that mother uses for cooking.
Item:
study of phenomena occurring with substances and products in the kitchen.
Target: find out how our kitchen is similar to a chemical laboratory.
Tasks:
1. Find out what chemistry and chemical substances are.
2. Conduct chemical experiments with edible products.
3. Prove that the kitchen is a whole chemical laboratory.
http://www.o-detstve.ru
Hypothesis:
salt-
sodium chloride;
vinegar-
acetic acid
baking soda - sodium bicarbonate
sugar-
sucrose
We have chemical reagents in our kitchen!
starch-polysaccharide
milk - lactose
Experience with sunflower oil
Conclusion: having studied the literature, performed experiments,
we are convinced that many processes,
chemical phenomena occurring in our kitchen.
Hypothesis:
Kitchen - chemical laboratory
Thank you for your attention!
“Favorite drinks: tea and coffee.”
Research work in chemistry.
Completed by: 10th grade student
Dutova Natalya Nikolaevna
Head: Firsova A.A.
chemistry teacher.
With. Olkhovatka 2009
Introduction.
For my research work, I chose the topic: “Favorite drinks - tea and coffee.” The relevance of this topic is obvious. After all, a person consumes tea and coffee in his diet every day, but not everyone knows what substances these drinks contain, whether they bring benefit or harm, and what effect they have on the human body. I also became interested in what I actually eat, so I chose this topic.
I believe that these drinks - tea and coffee - bring people not only benefits, as many people think, but also harm. For example, the caffeine they contain acts directly on the central nervous system. It produces an almost immediate feeling of mental clarity and reduces fatigue. It also stimulates the release of sugar stored in the liver, which explains that high feeling caused by coffee, cola or chocolate (the big caffeine three). However, the side effects can be much greater than these pleasant sensations. And therefore, I will try to prove that coffee and tea bring people not only benefits, but also harm.
In my research activities, my goal is to prove that tea and coffee are both harmful and beneficial.
My main tasks are to study the composition of the drinks under study and conduct the necessary chemical experiments.
Leo Tolstoy was a big tea lover, who left the following review of the revered drink: “I had to drink a lot of tea, because I couldn’t work without it. Tea releases the possibilities that lie dormant in the depths of my soul.”
Now a little about the history of tea and coffee.
The first caravan with tea arrived in Russia in 1638 from Mongolia, and Moscow Ambassador Extraordinary Vasily Starkov solemnly presented Tsar Mikhail Fedorovich with a precious gift from Altyn Khan - four pounds of leaves of this unprecedented plant. At first we treated ourselves to the wonder with caution. But soon everyone recognized: “the drink is good and when you get used to it, it tastes much better.”
In 1885, the first industrial tea plantation was founded in Chakva (Adjara); since 1901, tea began to be grown in the Krasnodar Territory, and since 1912 - in Azerbaijan. Currently, tea is grown in many countries in Asia, Africa and America. India firmly holds the leading position.
Scientists have established that coffee was first drunk in Ethiopia, although it was not very popular here. In the 4th century, one of the Ethiopian tribes, having moved to Yemen, brought with them a coffee tree, and here coffee cultivation reached high perfection, and the locally prepared drink began to turn out much tastier than that of the Africans. In the first half of the 16th century, coffee was introduced to Turkey. In 1564, the first coffee shop appeared in Istanbul, where poets and scientists, artists and politicians gathered and drank a delicious black drink with pleasure. Within a few years, coffee shops spread throughout the country. In the mid-17th century, coffee entered Europe. Italy first became acquainted with it, and then, in 1652, the first coffee shop appeared in London. By 1693, there were more than 3 thousand coffee houses in the English capital. While coffee was winning the hearts and souls of the British, other peoples of Europe also did not remain indifferent to this drink. In 1672, “syrup from soot” began to be prepared on Place Saint-Germain in Paris, a little later the “Turkish drink” appeared in Bulgaria, Poland, Austria, Germany, Belgium, Holland, and by the end of the 18th century, “the black blood of the Turks”, “ grains of vigor from Kaffa began to be drunk in different countries of the American continent. In Russia, they apparently learned about coffee in 1665, when the court doctor prescribed Tsar Alexei Mikhailovich “boiled coffee, known to the Persians and Turks.” In 1884, Russian coffee imports already amounted to 508 thousand poods, and before the 1st imperialist war it reached 772 thousand poods.
CHEMICAL COMPOSITION OF TEA AND COFFEE.
Now let's get acquainted with the chemical composition of tea and coffee.
Tea contains water-soluble and insoluble substances: phenolic compounds, catechins, sugars, pectin substances, alcohols, acids (succinic, citric, lactic), amino acids, purine derivatives (caffeine, guanine, adenine, theopheline, theobromine), pigments, vitamins, enzymes, mineral and aromatic substances, proteins, cellulose, starch, fat-soluble vitamins.
Tannins
These are phenolic compounds, which make up 15–30%. The tannin in tea is tannin. The composition of tannins depends on the weather. During the rainy season, their number decreases, and during the sunny season it increases. The more tannins and compounds in dry tea, the higher the quality of the infusion, the better the color, astringency and aroma.
Alkaloids
These include caffeine, which has a stimulating effect, so tea has long been considered a drink of vivacity. The caffeine in tea does not accumulate in the body, but is eliminated from it, so you can drink tea more than other drinks containing caffeine.
Pigments
These substances are involved in the color of the infusion, which, depending on the type and variety of tea, can range from light yellow to red-brown.
Carbohydrates
Soluble carbohydrates are sucrose, fructose and glucose. The insoluble group of carbohydrates is starch, cellulose and other substances.
Pectins
Ash elements
High-grade tea contains a lot of potassium and phosphorus. Potassium helps normalize heart activity. Low grades are dominated by sodium, calcium, and magnesium. Iron salts and microelements such as fluorine, iodine, copper, and gold are found in tea. Fluoride is known to protect teeth from caries. Iodine is an anti-sclerotic element.
Vitamins
Tea is rich in vitamins. Vitamin C was first discovered by Japanese scientists in 1924–1925. Georgian tea leaves contain 3–4 times more of it than lemon juice. Of course, during the processing of raw materials, some vitamins are destroyed.
There are other vitamins B1, B2, PP, B15, rutin. It has been established that there is vitamin P in tea.
Tea has a lot of tannins, also tea – champion among drinks in terms of bioflavonoids content. Black varieties contain a substance - quercetin.
CHEMICAL COMPOSITION OF COFFEE
Caffeine, chlorogenic acids, essential oils, and methylpyridine were found in coffee.
Tea and coffee: harm or benefit?
Now we’ll find out whether these drinks bring us harm or benefit. Let's first talk about the properties of tea.
Tea contains a lot of tannins, which remove radionuclides and heavy metal salts from the body. Tannins also have an antimicrobial effect. Tea normalizes intestinal microflora, is useful for diseases of the gastrointestinal tract, and the bioflavonoids it contains strengthen the immune system. Green tea removes toxins, improves blood circulation and metabolic processes. This variety is rich in polyphenols. One of the groups of substances - catechins - has not only a preventive anti-cancer effect, but even blocks the growth of certain tumors, causes the expansion of skin pores, and increases sweating. Cosmetologists say that it biochemically cleanses pores, has a soothing, anti-inflammatory effect on sensitive skin, and is involved in regulating blood sugar levels. Thanks to the vitamin P content, tea improves blood circulation in small vessels. Therefore, it is useful to wash sore eyes with the drink. Stimulates the renewal of the endothelium - a thin layer of cells lining blood vessels. Relieves nausea, calms the stomach. Reduces the permeability and fragility of blood vessels. Medium strength tea reduces the heat a little. But too strong, on the contrary, increases the temperature. A weak infusion of tea lowers blood pressure, while a strong (especially sweet) infusion, on the contrary, increases it. Thanks to its quercetin content, tea prevents the formation of blood clots. Strong tea can cause tachycardia - increased heart rate and irregular heartbeat.
Now let's talk about coffee.
Caffeine, which is contained in coffee, activates brain activity and invigorates. And at the same time, the aroma of coffee, due to essential substances, calms the nervous system. Chlorogenic acids are found in coffee, the effect of which on the body is similar to a sleeping pill. Therefore, some people want to sleep first from this drink, and only then cheer up. A cup of strong coffee increases blood pressure by 15 mmHg after 10 minutes. Hypertensive patients can drink coffee only in the morning - very weak and with milk, which neutralizes the effect of caffeine. Contraindicated for arrhythmias - may cause an unpredictable reaction of the heart. Improves vascular tone in case of decreased cardiac activity, dizziness and headaches caused by low intracranial pressure and meteosensitivity. But for pain caused by spasms, it can cause harm. Acts as an antidote for carbon monoxide poisoning. Strengthens the production of gastric juice, increases acidity. Therefore, for gastritis and ulcers with high acidity, it is better to avoid coffee altogether or drink it only after meals and with milk. Stimulates the breathing center. Relaxes the muscles of the respiratory tract and may reduce the frequency of attacks in asthmatics. Sharpenes hearing and vision. Essential oils that add coffee aroma slightly irritate the intestines and promote the production of the hormone serotonin, a powerful natural antidepressant. A substance called methylpyridine, which protects against tumors, has been found in coffee. May be addictive. Large doses with constant use result in nervousness, irritability, and insomnia. Coffee with lemon has a strong anti-inflammatory and immunostimulating effect. An excellent remedy for colds. Reduces the formation of kidney stones. It has a relaxing and analgesic effect for cervical osteochondrosis and headaches.
ABOUT CAFFEINE.
Caffeine is a psychostimulant. They improve mood, the ability to perceive external stimuli, and psychomotor activity. They reduce the feeling of fatigue, increase physical and mental performance (especially when tired), and temporarily reduce the need for sleep (drugs that invigorate a tired body are called “doping” from English to dope - to give drugs).
Caffeine is a compound from the group methylxanthines. It is an alkaloid found in tea leaves (Thea sinensis), coffee seeds (Coffea arabica), cocoa seeds (Theobroma cacao), cola seeds (Cola acuminata) and other plants. Caffeine combines psychostimulant and analeptic properties. Its direct stimulating effect on the cerebral cortex is especially pronounced. Caffeine stimulates mental activity, increases mental and physical performance, motor activity, and shortens reaction time. After taking it, vigor appears, fatigue and drowsiness are temporarily eliminated or reduced.
The effect on higher nervous activity largely depends on the dose of caffeine and the type of nervous system. In small doses, caffeine has a predominant stimulating effect, in large doses it has a depressant effect. It should be borne in mind that for a weak type of nervous system, the excitation effect is achieved by introducing small doses of caffeine, while for a strong type, significantly larger doses are required.
Analeptic activity is associated with the effect of caffeine on the centers of the medulla oblongata. It has a direct stimulating effect on the respiratory and vasomotor centers. Increased and deepening of breathing occurs, which is especially clearly manifested when the respiratory center is depressed. In addition, caffeine stimulates the vagus nerve centers. The drug affects the spinal cord only in large doses. By facilitating interneuronal transmission of excitation, it enhances spinal reflexes.
A significant place in the pharmacodynamics of caffeine is occupied by its effect on the cardiovascular system. It consists of peripheral and central effects. Thus, caffeine has a direct stimulating effect on the myocardium. However, the centers of the vagus nerve are simultaneously excited, so the final effect will depend on the predominance of one or another influence. Usually changes in heart activity (if they occur at all) are small. In large doses, caffeine causes arrhythmias of the heart.
There are central and peripheral components in the action of caffeine in relation to vascular tone. By stimulating the vasomotor center, caffeine increases vascular tone, and when directly affecting vascular smooth muscles, it reduces their tone.
Caffeine has mixed effects on different vascular regions. For example, coronary vessels most often dilate (especially if cardiac output is increased). At the same time, the cerebral vessels are somewhat toned. The latter appears to explain the beneficial effects of caffeine on migraines. Caffeine has a moderate myotropic antispasmodic effect on other smooth muscle organs (bronchi, bile ducts). Caffeine has a stimulating effect (central and direct) on skeletal muscles.
Blood pressure changes are even more complex because it depends on the cardiotropic and vascular effects of caffeine. Typically, if blood pressure is normal at baseline, caffeine does not change it or increases it very slightly; if the drug was administered against the background of hypotension, then blood pressure increases (normalizes).
Caffeine increases basal metabolism. Increases glycogenolysis, causing hyperglycemia. Increases lipolysis (the content of free fatty acids in the blood plasma increases). In large doses, it causes the release of adrenaline from the adrenal medulla.
Many authors associate the central effects observed with the use of caffeine, the effect on smooth and striated muscles, and changes in metabolism with the accumulation of cyclic adenosine monophosphate (cAMP). This occurs, apparently, partly as a result of inhibition of phosphodiesterase and, in connection with this, a disruption in the process of cAMP breakdown. Caffeine is particularly potent in inhibiting phosphodiesterase in the brain and heart. However, the effect on phosphodiesterase is observed only at very high concentrations of caffeine, exceeding therapeutic levels. In recent years, evidence has accumulated that a more important component of the action of methylxanthines (caffeine, theophylline) is obviously their antagonism with adenosine. It is important to note that the latter is observed at therapeutic concentrations of methylxanthines. This point of view is also supported by the fact that methylxanthines and adenosine cause opposite effects:
| Direction of action | Methylxanthines | Adenosine |
| central nervous system | Excitation | Oppression |
| Release of catecholamines | Rising | Decreases |
| Heart rate and strength | Are increasing | Are decreasing |
| Renal blood flow and renin secretion | Increases | Decreases |
| Release of histamine from mast cells | Decreases | Increases |
| Lipolysis in adipose tissue | Rising | Decreases |
In addition, the noted effects of adenosine have been shown to be reversed by methylxanthines. This occurs as a result of the fact that methylxanthines block adenosine receptors, being competitive antagonists of adenosine.
Under the influence of caffeine, the secretion of the gastric glands increases, which can be used for diagnostic purposes. The use of caffeine for gastric pathologies (gastritis, peptic ulcers, tumors) helps to differentiate functional disorders from organic ones.
To a small extent, caffeine increases diuresis, which is associated with inhibition of the reabsorption process of sodium and water ions in the renal tubules. In addition, caffeine dilates the blood vessels of the kidneys and increases filtration in the renal glomeruli. Caffeine and especially its water-soluble salts are well absorbed from the intestine (including the colon). The main part undergoes biotransformation (demethylated, oxidized). About 10% of caffeine is excreted unchanged by the kidneys.
With prolonged use of caffeine, mild addiction develops. Mental dependence (theism) may occur.
Caffeine is used to stimulate mental activity, for fatigue, migraines, and hypotension. It is part of many combination drugs in combination with non-narcotic analgesics (Citramon, Pyramein tablets, etc.) and ergot alkaloids (Coffetamine tablets).
Side effects manifest themselves in the form of nausea, vomiting, anxiety, insomnia, tachycardia, cardiac arrhythmias.
Caffeine is contraindicated in cases of severe arterial hypertension, atherosclerosis, sleep disorders, and glaucoma.
6. How does caffeine affect health and life expectancy?
"A large-scale study found fewer suicides among coffee drinkers compared with those who abstained from it. A study of nearly 130,000 Northern California residents and records of 4,500 deaths found no other link between coffee, tea and mortality."
Cardiologist Arthur Klotsky said of the surprising results: "This is not misleading, as our study was very broad, including a multiracial population, and looked in detail at multiple factors that influence mortality, such as alcohol consumption and smoking." No association was found between coffee consumption and risk of death. There was a "weak" correlation between daily coffee or tea consumption and the risk of heart attack - but no link with other cardiovascular diseases, such as hypertension or heart attack."
The study was conducted by the disease prevention organization Kaiser Permanente.
Tea and health
Leo Tolstoy was a big tea lover, who left the following review of the revered drink: “I had to drink a lot of tea, because I couldn’t work without it. Tea releases those possibilities that lie dormant in the depths of my soul.”
Because tea contains many vitamins and nutrients, it helps in the fight against scurvy. Studies have shown that tea infusion reduces the intensity of inflammatory processes, so it can be used in the treatment of rheumatism and for washing the eyes for blockages and conjunctivitis.
Green tea infusion has a positive effect on heart function. This high-calorie, vitamin-rich product enhances the performance of the heart muscle, stabilizes blood pressure, and improves well-being. It has been noted that people living in countries where tea consumption is traditionally high are less susceptible to cardiovascular disease.
Most people know that warm tea with a small amount of milk is an excellent diuretic, and with raspberry jam it is anti-cold and diaphoretic. The burned areas of the skin are sprinkled with crushed dry tea. It is recommended to chew a small pinch of dry tea and then rinse your mouth to remove the smell of garlic. A strong infusion of tea helps with indigestion. For headaches of non-hypertensive origin, it is good to drink a glass of strong tea. This drink also reduces the feeling of fatigue.
It has been established that the presence of vitamin P in tea reduces capillary fragility, which means it is a means of preventing atherosclerosis.
It is also known that tea contains a high percentage of fluoride, so we can talk about its positive effect on the preservation of tooth enamel and the prevention of caries if sugar is not included in the infusion.
You have a headache?
To get rid of a headache, sometimes drinking a cup of strong, sweet tea is enough. The secret is that it contains up to 0.05 grams of caffeine, the same amount as, for example, a pircofen tablet. But the caffeine contained in tea has a milder effect than a chemically pure drug. Besides, drinking a cup of a tasty and aromatic drink is more pleasant than swallowing a bitter pill. This is why some people prefer tea to patent medicine.
But headaches have different causes. And a cup of tea doesn't help everyone. If tea does not help you, consult a doctor.
Eyes are tired
The eyes usually get tired from working for a long time at a desk in poor lighting, sitting for a long time in front of the TV on, reading a newspaper on a moving bus... A person whose eyes are tired can be recognized by a dull look and reddened eyelids.
If your eyes are tired, lie down on the sofa and place two sterile cotton swabs soaked in a strong infusion of a mixture of green and black tea on your eyelids. Wrap the remaining wet tea grounds in gauze and also place them on your eyelids on top of the tampons.
With tampons and gauze, lie on the couch for 15-20 minutes. If necessary, repeat this procedure in the morning.
Wash your eyes with teaYou've probably heard that rinsing your eyes with strong old tea infusion helps with conjunctivitis. Yes, it helps. But, according to ophthalmologists, a strong, fresh, quickly cooled tea infusion works much more effectively for conjunctivitis.
How to rinse your eye?
Turn your eyelids out with your fingers, then rinse your eyes with a stream of tea infusion from a large syringe.
A large syringe will come in handy if you accidentally burn your eye with a chemical, such as vinegar essence.
As soon as possible (due to delay, you can lose your vision), fill a large syringe with an infusion of fresh, cooled, weak tea, turn your eyelids out with your fingers and thoroughly rinse your eyes with a stream of tea.
Repeat this procedure several times. After this, cover your eye with a bandage and hurry to the ophthalmologist. You should definitely see him, even if you feel relief after washing your eye.
I have a toothache
Take a strong infusion of green tea into your mouth, into which you first add a few crushed cloves of garlic. Keep the infusion in your mouth until the pain goes away. The pain goes away thanks to the effect of the infusion, which has bactericidal and astringent properties, on the mucous membrane of the gums. By the way, you will eliminate the smell of garlic from your mouth if you chew a pinch of dry green tea.
Hypertension recedes
Studies by Japanese scientists have shown that in patients with stage I and II hypertension who drink green tea for a long time, blood pressure can decrease by 10-20 percent.
The rules for preparing a tea drink for the treatment of hypertension are simple.
Before brewing, crushed dry green tea is lightly washed with warm boiled water to reduce its caffeine content, which has a stimulating effect on the cardiovascular system. Then the washed tea is poured with boiling water (at the rate of 3 grams of tea per 100 grams of water) and infused for 10 minutes. Drink a glass of it 3 times a day after meals. The total amount of liquid consumed during the day is reduced, taking into account the tea, to 1-1.2 liters so as not to overload the cardiovascular system.