Interesting research papers in chemistry. Research work in chemistry

Research

TOPIC: Detergents for dishes and their properties. Influence of detergents on the corrosion of metals.

Introduction page 2-3

Chapter 1. General information about dishwashing detergents pages 4-5

1.1 Dishwashing detergents page 4

1.2 Ingredients for dishwashing detergents pages 4-5

Chapter 2 Diagnosing Dish Detergents page 6-8

2.1 Diagnosing the use of dishwashing detergents page 6

2.2. Composition, properties and features of the use of detergents page 7

2.3. Physical and chemical properties of dishwashing detergents. pp. 7-8

2.4. Influence of dish detergent solutions on page 8

the course of corrosion processes of iron objects.

Conclusion page 9

References page 10

Appendix page 10

Introduction

The twenty-first century is the time when information has become the foundation on which all spheres are held human life. Therefore, each person must be sure that the information he owns is reliable and will not bring spiritual or physical harm to him and those around him. Streams of information reach us from everywhere, but the main source is the media. And often even an educated and wise person cannot determine whether they are trying to deceive us by using advertising tricks or only slightly exaggerate the merits of the goods and services offered. Advertising has become an integral part of our lives. Sometimes it really helps to navigate the variety of goods and services, and sometimes it promises just “miracles”. Thanks to the active advertising policy of manufacturers, today almost every family uses special means. So, scientists have calculated that a Russian family of 4 people annually washes about 5 tons of dirty dishes! The first MCs appeared over 5000 years ago in the Middle East. But their role in our life has not changed so far. MS is currently used to remove various kinds dirt: stains on clothes, rust, dirty dishes, etc.

In terms of composition, dishwashing detergents are close to shampoos and shower gels. That is, hygiene products. And they are subject to special security requirements. All this is good, however, dishwashing detergents are listed as household chemicals. This means that they do not need a hygiene certificate to guarantee safety. The requirements for both toilet bowl cleaner and dishware are the same. Manufacturers may subject their products to safety testing, but voluntarily. Chemists admit: this certificate only guarantees that at the time of use you will not get poisoned, do not spoil the skin of your hands. But what happens in the course of time in the body, into which the remnants of the detergent constantly enter, such studies have not been conducted.

With the ever-increasing number of new chemicals coming into circulation, topical issue is their study in order to obtain information about the potential hazard of substances and the development of preventive measures to prevent adverse effects on the human body and the environment. Among the complex of environmental factors subject to hygienic control, household chemicals (TBC) deserve great attention due to their mass production and use, the variety of components that make up the formulations, as well as their possible direct impact on the human body. As you know, after use, all chemicals enter the environment and adversely affect it, but we do not think about it. Therefore, we decided to devote our work to household chemicals and, having studied the composition of MS for dishes, determine how safe their use is.

We believe that our work is very relevant today. We cannot do without MS, but their use often harms our world. To understand how to deal with the harm that MCs do to us, we first need to learn more about them than advertised. We decided to conduct a study in our school to identify the means that use most in demand, and analyze what justified the choice of participants in our study. To say yes or no to MS is the business of each person, but if certain rules are followed, then the risk to health will be minimal.

Practical significance The work consists in the fact that the information obtained from the results of the research work can be used to educate the population of the village about the dangers of certain detergents, the negative impact of SMS on human health, and the increased corrosion of metals from which plumbing is made.

Target work: to study the physico-chemical properties of detergents, to investigate the effect of detergents on the corrosion of metals from which plumbing is made.

Tasks :

1. Study the literature on this issue;

2. Identify the most commonly used brands of dishwashing detergents at home;

3. Study the composition, data of dishwashing detergents using their labels.

4. Investigate the physical and chemical properties of detergents;

5. Consider the effect of detergents on metal objects (nail).

Object of study : liquid dishwashing detergents.

Subject of study: properties and safety of using detergents for dishes, corrosion of metals.

Hypothesis: if you have complete information about the composition and properties of detergents, thencan save human health, prevent damage to sanitary ware made of iron.

In accordance with the objectives of the study, methods of systematization were used theoretical material, research methods and methods of observation, generalization of the accumulated material.

Chapter 1: Understanding Dishwashing Detergents

1.1 Dishwashing detergents and their properties

Special dishes detergents first appeared in the 1950s. Means for hand wash dishes are available in the form of a liquid or gel. Gel-based products are considered more effective than liquid ones.

The main properties of the product is its washing ability. A big plus of the product is its ability to effectively deal with oil and grease contaminants in cold water, this is achieved by selecting the optimal surfactant composition.

Another important property of the hand dishwashing detergent is its gentle effect on the skin of the hands. It is worth noting that manufacturers' claims that their products have a pH level of 5.5 cannot in any way guarantee the absence of irritation, especially in people prone to allergies. Therefore, while washing dishes, the skin needs protection. The product should contain emollients and do not forget that hands can be protected from harmful effects using ordinary rubber gloves.

A lot about dishwashing detergent can be said by its composition.

1.2 Composition dishwashing detergents

The basis of the detergent is surface-active substances (surfactants). It is they who determine its washing ability.

Surfactants are divided into two types: ionic and non-ionic (non-ionic).

The fundamental difference is that nonionic surfactants are not subject to electrolytic dissociation, i.e. they do not decompose in water into positively and negatively charged ions; ionic surfactants, when interacting with water, decompose into ions, some of which have adsorption (surface) activity, others (counterions) are adsorption inactive.

Ionic surfactants are called anionic if the surface-active ions carry a negative charge, and cationic if the positively charged ions are surface-active. Some surfactants, depending on the conditions under which they are used, exhibit either anionic or cationic properties, which is why they are called amphoteric or ampholytic. Anionic surfactants are organic acids and their salts. Cationic - bases, usually amines, and their salts. In the world production of surfactants, most of the anionic substances.

Synthetic detergents necessarily contain a number of excipients that improve their washing ability. The detergent compositions sometimes include alkaline salts of weak inorganic acids (sodium carbonate and bicarbonate, sodium silicates, phosphates of various compositions), neutral salts (sodium chloride), salts of peroxide acids with bleaching and disinfecting properties (sodium perborate and percarbonates). Exactly these chemical substances and enter into chemical reactions with the metals from which plumbing is made, under the influence of these substances, corrosion of metals occurs. Corrosion results in billions of dollars in losses every year, and solving this problem is an important task. The main damage caused by corrosion is not the loss of metal as such, but the enormous cost of products destroyed by corrosion. That is why the annual losses from it in the industrial developed countries so great.

An important role is played by the organic components of surfactants: carboxymethyl cellulose, which prevents the re-deposition of contaminants from the washing solution onto the washed surface, and the so-called hydrotropes, which increase the solubility and accelerate the dissolution of surfactants in water.

Some detergents contain enzymes that remove insoluble protein contaminants, organic bactericides, and foam stabilizers.

Aromatic substances (perfumes) are added to many detergents, designed to eliminate unpleasant odors and give the washed surface a fresh scent. True, the smell of apple, lemon, or, for example, forest berries does not mean the presence in this product of extracts of the above named fruits.

Also, the composition of dishwashing detergents may include substances that soften the negative effect on the skin of the hands. The most common additives are glycerin, silicone, and plant extracts. Glycerin and silicone have a similar effect, they create on the skin protective film preventing it from drying out. At the same time, the surface film created by silicone is able to protect against the penetration of substances harmful to the skin contained in the detergent.

Plant extracts soften the skin, have a calming effect, relieve irritation that can be caused by individual components of surfactants (for example, aloe vera milk has such an effect). But even with all undoubted merits These supplements cannot guarantee your skin is completely safe.

Chapter 2: Diagnosing Dishwashing Detergents

In order to find out which of the means are the most used, we interviewed students, teachers and school staff. 50 people took part in the survey.

Poll data shows that Fairy is the most popular medium. It is used by 19 people from among the respondents, which is 38%. Next in descending order of popularity are: "AOS" - 11 people, 22%; "Myth" - 7 people, 14%; "SORTI" - 7 people, 14%; "Drop" - 6 people, 12%.

2.2. Composition, properties and features of the use of detergents.

To study the composition, properties, features of the use of dishwashing detergents, the labels of the products indicated in the user survey were studied. As a rule, no one reads the instructions for washing dishes, but this does not relieve the manufacturer from the need to put this information on the label.

The research data are shown in Table 1.

Table 1.

Composition, properties and features of the use of detergents.

Fairy

AOC

MYTH

SORTI

A drop

Volume/ml

Price, rub.

Shelf life

18 months

24 months

Compound

5-15% anionic and nonionic surfactants, perfume, preservative, citroneplol, limonene and linalool.

5-15% anionic and nonionic surfactants, ethylenediaminetetraacetic acid salt, flavor additives, preservatives

anionic and nonionic surfactants, sodium chloride, lemon acid, preservative, perfume composition, citric acid

Water, anionic and nonionic surfactants, ethylenediaminetetraacetic acid salt, flavor additives, preservatives,

water, surfactant,

sodium chloride, citric acid, preservative, perfume composition, citric acid,

apply a small amount to a damp sponge

Put a few drops of the product on a damp sponge

Apply a small amount to a damp sponge

6. Precautions

In case of contact with eyes, rinse with water

Keep away from children

Protect from sunlight. Keep away from heating appliances. Keep away from children. In case of contact with eyes, rinse with water.

Keep out of reach of children, avoid contact with eyes.

This table allows you to do the following findings:

With an equal amount of detergent, the price of the funds is not the same.

The more expensive products include "Fairy", "AOC", the cheaper ones are "Myth", "SORTI" and "Drop".

The shelf life of all funds is almost the same.

The main component of MS are surfactants.

in addition to surfactants, detergents contain dyes, preservatives, perfume composition, but the labeling of these substances is not indicated, which does not allow us to conclude that they are safe for humans.

The packages do not indicate the exact amount of the product needed for use. It only says “put a small amount on a sponge or dish” or “drip a few drops…”.

Almost all means, except for "Fairy” contain a warning: “Keep out of reach of children” and describe what to do if the product gets into the eyes.

Much attention is paid to advertising data on the MC label: manufacturers indicate that all products effectively remove fat not only in hot, but also in cold water, they are easily washed off with water without leaving streaks. On the product label "Fairy» indicates that it complies with the Russian standard for washability from dishes.

2.3. Physical and chemical properties of dishwashing detergents.

Experience 1: Study of the pH of the solution.

One of the requirements for the use of dish detergents is that they must have a neutral or slightly acidic pH value of the solution (pH = 5.5-7).

We took a 0.1% solution of each agent to determine the pH of the solution, examined it using a device for determining the pH of solutions. The results of the experiment are shown in table 2. Conclusion: All products are pH neutral.

Table 2:

Chemical properties of dishwashing detergents.

Indicator

Fairy

AOC

Myth

SORTI

A drop

1. solution pH

7,68

7,7

6,0

Content

phosphates

Experience 2 : Phosphate content in dishwashing detergents .

The presence of phosphate additives in detergents leads to a significant increase in the toxic properties of surfactants. They penetrate into the microvessels of the skin, are absorbed into the blood and spread throughout the body. This leads to a change in the physical chemical properties the blood itself and impaired immunity.

A 0.1% solution of each agent was tested with silver nitrate. There were no yellow or white precipitates in the test tubes. A yellow precipitate indicates the presence of phosphate ions (Ag 3 PO 4 ) in the samples, a white precipitate indicates the presence of chloride ion (AgCl ) in the samples. The results of the experiment are shown in table 2.

Conclusion: Phosphate additives were not found in detergents.

2.4. Influence of dish detergent solutions on processes

corrosion of iron objects.

When disposed of, used dish detergent solutions come into direct contact with metal pipes sewerage, and when washing with metal utensils.

For the study, a 0.1% solution of each detergent was prepared and an iron nail 80 mm long was lowered into each. The experiment was carried out at room temperature. Used as a control sample tap water. The experiment was carried out with three repetitions.

On the first day, rust appeared on the nails in the following products: “AOS", "a drop SORTI". On the second day, a rust coating appeared in a test tube with tap water and on a nail lowered intoFairy» . In the "MIF" tool, rust appeared in the test tube on the third day, while the nail remained clean. In the following days, the rust coating on the nails increased, and the fastest in the means: “Fairy”, “AO S", "a drop SORTI". Rust was deposited at the bottom of the test tubes - a brown precipitate. By the end of the observation, the sediment height was different in the test tubes: “AOS"- 10mm, " Fairy"-7mm," drop SORTI"- 9mm, "MIF" - 4mm, "Drop" -9 mm, water - 3mm.

Conclusion: All studied solutions of detergents for dishes contribute to increased corrosion of iron objects, which means they have a negative effect on sewer pipes and metal utensils.

Final part

Findings:

The most popular among the population are the means: "Fairy",

« AOS".

Detergent labels contain a large amount of advertising promises,

but not full information on the composition and labeling of ingredients, on the method of application.

All agents are highly soluble in water.

4. All products are pH neutral.

5. Products do not contain harmful phosphate additives.

6. All investigated solutions of detergents for dishes contribute to increased corrosion of iron objects, and therefore have a negative effect on sewer pipes and metal utensils.

We want to advise you to be more responsible in the choice of detergents and not to let the advertisements deceive you. Do not forget that our children and grandchildren will live on this planet, and we must take care of their future and health. Also, do not forget that our skin suffers from the use of certain detergents. Environment. We also want to advise you to be more careful with detergents and do not forget that they contain components that can cause rashes, chemical burns, irritations and allergies. Always read the precautions on the back of the packaging and keep detergents out of the reach of children.

We are aware that the consumption of detergents by people cannot be stopped, and even reduced. Moreover, with an increase in the population of our planet, the number and variety of detergents inevitably increase, which adversely affect not only humans, but also the environment.

We hope that as progress progresses, safer detergents will be invented that will be able to completely dissolve in water without forming harmful chemical compounds. The information obtained during the research work can be used in teaching a school course in chemistry, biology, ecology, classroom hours, in conversations with students and parents, in optional classes in chemistry and ecology.

Literature:

1. Ambramzon A.A. etc. Surfactants. Synthesis, analysis, properties,

application. L., 1988.

2. Ashikhmina T.Ya. School environmental monitoring. Educational and methodical allowance / Ed. T.Ya. Ashikhmina. – M.: Agar, 2000.

3. Bogdanov I.I. Conversations about ecology: Proc. allowance. - Omsk, 1995.

4. Shpausus Z. Journey into the world of chemistry. M .: "Enlightenment", 1967.

Schwartz A., Peri D. Surfactants: their chemistry and technical applications. M., 1953.

Kharlampovich G.D. etc. Many Faced Chemistry. - M .: "Enlightenment", 2004

Applications

Observation: 4.11.15

Observation: 11/10/15

Stages of work: Viewing and analyzing labels on products of several manufacturers of washing powders "Tide" "Tide" and "Dosia", "Dosia", studying the composition of shampoos "Head "Head & Shoulders", Shoulders", "Sebozol", baby cream, baby Johnsons baby oils on their labels. Study of information on packaging; Watch commercials for Tide, Tide and Dosia laundry detergents. Dosia. Evaluation of the reliability of advertising with the help of experience from the standpoint of chemistry; Compilation of tables.

OBJECTIVES OF THE RESEARCH: I SET MYSELF THE OBJECTIVE TO CHECK THE RELIABILITY OF THE ADVERTISING OF WASHING POWDERS. THEN STUDY THE COMPOSITIONS OF WASHING POWDERS, CHILDREN'S CREAM AND OIL, SHAMPOO. Problem solving: For the experiment, I chose an advertisement for washing powders "TIDE" and "DOSIA", baby cream, oil "Johnsons baby", shampoos "Head & Shoulders", "Sebozol".

DESCRIPTION OF THE RESEARCH I HAVE TO DO. Take "TIDE" and "DOSIA", "Head & Shoulders" and "Sebozol", baby cream and "Johnsons baby". Analyze the composition of each product. Take "TIDE" and "DOSIA", "Head & Shoulders" and "Sebozol" , baby cream and Johnsons baby. analyze the composition of each product. Take fabrics stained with four types of stains and soak in TIDE and DOSIA. Take fabrics stained with four types of stains and soak in TIDE and DOSIA. Analyze the results obtained (estimated the degree of purity). Analyze the results obtained (estimated the degree of purity). The results of the study are given in the table. The results of the study are given in the table.

I STAGE. VIEWING AND ANALYSIS OF LABELS ON PRODUCTS. Viewing and analyzing labels on products of several manufacturers of Tide and Dosia washing powders, studying the composition of Head & Shoulders, Sebozol shampoos, baby cream, baby oil "" according to their labels. Studying the information on the packaging. Viewing and analyzing labels on products of several manufacturers of Tide and Dosia washing powders, studying the composition of Head & Shoulders, Sebozol shampoos, baby cream, Johnsons baby baby oil according to their labels. Studying the information on the packaging.

Composition of powders: "TIDE" "DOSIA" 15-30% - anionic surfactants 15-30% - anionic surfactants phosphates, phosphates, less than 5% - cationic surfactants less than 5% - cationic surfactants oxygen-containing bleach oxygen-containing bleach nonionic surfactants nonionic surfactants enzymes enzymes optical bleach optical brightener 5-15% anionic surfactants 15-30% water softening components oxygenated bleach less than 5% non-ionic surfactant enzymes antifoaming agent fragrance

SHAMPOO COMPOSITION: Water (H2O) Water (H2O) Ammonium Lauryl Sulfate (C12H29NO4S) Ammonium Lauryl Sulfate (C12H29NO4S) Sodium Chloride (NaCl) Sodium Chloride (NaCl) Glycol Distearate Glycol Distearate Prition Zinc Prition Zinc Perfume Perfume Sodium Citrate (Na 3 C) 6 H 5 O 7) Sodium citrate (Na 3 C 6 H 5 O 7) Citric acid (C 6 H 8 O 7) Citric acid (C 6 H 8 O 7) Benzyl alcohol (C 7 H 8 O) Benzyl alcohol ( C 7 H 8 O) Water (H2O) Water (H2O) Sodium laureth sulfate Sodium laureth sulfate Sodium chloride (NaCl) Sodium chloride (NaCl) Ketoconazal Ketoconazal Glycerin (C 3 H 5 (OH) 3) Glycerin (C 3 H 5 (OH) 3) "Head & Shoulders" "Sebozol"

OIL AND CREAM COMPOSITION: Vaseline oil Vaseline oil Isopropyl ether Isopropyl ether Aloe Barbadensis Aloe Barbadensis Vitamin E Vitamin E Perfume Perfume Glycerin (C 3 H 5 (OH) 3 Glycerin (C 3 H 5 (OH) 3) Oil Vaseline Oil Vaseline Oil extract calendula flowers calendula flower oil extract aloe vera gel aloe vera gel CO2 extract CO2 chamomile extract chamomile "Johnsons baby" "Baby cream"

CONCLUSION: We do not deny the need for advertising and its important role in life modern man, but we urge you to be very thoughtful and critical of everything that advertising companies bring down on us from the pages of newspapers, from TV screens, from numerous posters. flyers and brochures. When reading any advertisement, try to find out whether its content contradicts the laws or concepts of the natural sciences that we study at school.

Research work of students in chemistry

from the work experience of a chemistry teacher Gabdrakhmanova T.V.

"MBOU secondary school No. 5", Usinsk, Republic of Komi

Doubting, we start to explore

and by searching, we find the truth.
Pierre Abelard

Introduction

One of the main functions of a teacher is to teach and develop the student's personality. Organization is of particular importance research activities which has a significant impact on the personal and professional development of students.

For many years I have been organizing research work among students in grades 8-11 in chemistry at our school.

aimresearch work is the education of an inquisitive, actively cognizing the world, possessing the basics of the ability to learn a student who knows how to listen and hear others.

Tasks:

develop the ability to design their activities (educational, research);

develop communication and Creative skills students;

improve the skills of working with the methods necessary for conducting research - observation, measurement, experiment;

draw up the results of work, present their work at various competitions;

use the experience of students to gain new knowledge;

development of the ability to work independently with various information.

Relevance of research work:

Search the most efficient between innovation trends educational process and traditional technologies student learning;

the need to form a unique creative personality capable of thinking outside the box.

teaching students how to search, systematize and process the information received through independent research activities.

Organization of research work at chemistry lessons

When organizing research work, theoretical training is necessary, which students receive in traditional classes for the primary consolidation of knowledge.

Students receive elements of research work at chemistry lessons, but various problems arise, as schoolchildren are very vague about research methods, stages of work, and presentation of the results of their research work. It is difficult for them to select sources of information for a topic, generate ideas, find ways to solve problems, analyze, compare, make generalizations and conclusions, correlate what has been achieved with previously set goals and objectives.When students are prepared theoretically, one should applyrockywith elements of research and lessons-research. To stimulate interest in research activities in chemistry lessons, it is necessary to create a situation of success.

Lessons with elements of research.

Students work out in the lesson certain teaching methods that make up research activities.. What wouldstudents to offer to conduct a study are required to form their concept of the subject and object of research, a hypothesis, to show ways to test hypotheses. The research algorithm for students can be proposed using the example of a simple problematic task with a chemical content. For example, “What properties should the oxide and hydroxide of an element with serial number 13 have?” (Appendix 1). After completing the work, students can be offered independent research on the problem: “What are the properties of hydroxide chemical element, if the electronic structure of the atom is expressed by the scheme: 2e; 8e; 5e? According to the content of the elements of research activity, various types of lessons are distinguished: lessons on choosing a topic and research method, working with information sources, lessons with conducting an experiment, listening to messages, defending abstracts, etc.

The role of problem-based learning is very important in developing the research skills of students. The problem situation encourages students to think (analysis, synthesis, generalization, concretization, etc.) When considering the topic "Corrosion of metals", you can create a problem situation. The child delivers a message in which he talks about the dangers of corrosion. The speaker aims to give general idea about corrosion and the harm caused by this phenomenon. Lines from the report: “Corrosion causes not only direct damage (about one third of the metal produced in the world is lost annually from it), but also indirect: after all, metal constructions(cars, roofs, monuments, bridges). We define the problem that should be solved in the lesson: how to protect metals from corrosion? Students propose and justify methods for protecting metals from corrosion.

chemical experiment is one of the ways to form and develop the research skills of students. The experiment in the lesson is used to create a problem situation, as well as a means of confirming or refuting the hypotheses put forward by students. When studying the topic "Hydrolysis of salts" at the beginning of the lesson, you can conduct a laboratory experiment and use universal indicator paper to determine the environment of salt solutions. Observations can be recorded in a table.

After the experiment, together with the students, we put forward a problem. Salts are considered as the result of a neutralization reaction. Why do salt solutions have different environments? Based on known knowledge about dissociation, students put forward various hypotheses. Students recall various signs of the classification of acids and bases, analyze the formulas of the proposed salts. During the conversation, students come to the conclusion that hydrolysis occurs, which is one of the chemical properties of salts.

Lesson study

At the lesson-research, students master the methodology of scientific research, establish the stages of scientific knowledge. Students master research knowledge and skills in stages, gradually increasing the degree of independence of students in their research educational activities..

In research lessons, various forms of teaching students are used: individual, group, pair, collective. Preference is given to work in groups of 2-4 people, as work in a group contributes to the formation of communicative OUUN. To avoid the disadvantages of group work (conflicts, "hide behind other people's backs", etc.), the rules of group work are developed and used..

Workshop Lesson

During the workshops, students also work in groups. Each group, consisting of 2-3 people, receives an experimental task that must be completed during the lesson. When conducting a workshop for students, an instruction is created that, according to certain rules, consistently establishes the actions of the student.

Based on the experience, the following structure of practical lessons can be proposed:

Communication of the topic, purpose and objectives of the workshop;

Updating the basic knowledge and skills of students;

Motivation of educational activity of students;

Familiarization of students with the instruction;

Selection of necessary didactic materials, teaching aids and equipment;

Performing student work under the guidance of a teacher;

Compilation of a report;

Discussion and theoretical interpretation of the results of the work.

This structure can be changed depending on the content of the work, the preparation of students and the availability of equipment. Practical lessons are held in the 11th grade, for example, on the topic "Obtaining, collecting and studying the properties of gases", "Solving experimental problems in inorganic and organic chemistry."

In teaching subjects, the main task is, first of all, to interest students in the process of cognition: to teach them to ask questions and try to find answers to them, to be able to explain the results, to draw reasonable conclusions. The introduction of a research approach helps to increase the motivation of educational activities in teaching chemistry.

Research work at school can be varied. Students receive research skills in chemistry lessons at practical work, which combine a variety of tasks: experimentaltasks, computational tasks that require theoretical preparation for work, and reflect the main stages of research activity.

When solving experimental problems, students see the connection of chemistry with life, which contributes to the development of interest in studying the subject, as well as to prepare them for the conscious implementation of practical work (Appendix 2). Research activities of students are carried out both in chemistry lessons and outside of school hours.

Research work after school hours+

- identification of talented and gifted students

Many students are able to engage in research, and even more so in research activities. It is important to be able to identify talented and capable students. It should be borne in mind that the overall performance of a student is not the main indicator of his real abilities. It is more difficult to identify students' readiness for this species activities. Necessaryfind a student who is interested in it and who will bring the work to the end.

In the classroom, such children are noticeable when performing practical and laboratory work, drafting projects, making presentations. When checking such tasks, it is necessary to pay attention to the creative approach to completing tasks, to the use of additional literature. During the presentation of such work, students are invited to discuss what they liked about this work and what else can be recommended. After the presentation, it is proposed to answer several questions aimed at identifying attitudes towards this type of activity.

When analyzing such speeches, you need to pay attention to those students who show a stable interest in this type of work. In the future, these children can be invited to participate in research work.

- formation of interest in scientific creativity

Students do not always show interest in research work, so it is necessary to focus on the diligence and responsibility of the student. How to get the student interested? To do this, you can use several methods. First, to convince that participation in research work will be useful in later life, outside of school. Secondly, knowing that teenagers strive to somehow stand out, to be different from the majority, participation in research work will allow you to feel your special position among classmates. Third, create an atmosphere of competition.

- work with literature

Any activity, both a school essay and a doctoral dissertation, is impossible without working with literature sources. It is necessary to explain and show the student that the literary source is the basis of his work. During research work, students have to work with various sources information. The task of the student is to learn how to work with the source, to acquire the skill independent work, correct design. It is necessary to give some recommendations when working with literary sources. Explain to students that not all of the collected information may be needed, do not try to include all the collected material in the work.

- practical part of the work

During the practical part, students identify research tasks, put forward hypotheses and test them, conducting theoretical or experimental research, and process the results. The role of the teacher at this stage of the organization of research activities is not dominant. The teacher cooperates with the student, advises, suggests how to work with the equipment correctly, set up an experiment.

Fulfilling Scientific research, students acquire the skills of independent creativity, independent acquisition of new knowledge, information and their practical application which will be useful in any field of activity.

- presentation at scientific conferences

Scientific and practical conferences of students are held annually at the school. The success of a presentation at a scientific-practical conference depends on how well and confidently the students can present their work in the section, prepare a computer presentation, the text of the speech. It is necessary to clearly study the criteria for evaluating the work. The defense of the work will be effective when the student is fluent in information, is oriented in all parts of the work performed, knows the terms, has the skills of oratory, and is well prepared to speak at the conference. A student doing research shows considerable independence at all stages of work. In such children, their cognitive activity grows and, as a rule, the quality of knowledge in the subject increases. Gained experience and research skills of studentsinfluence the quality of experiments in practical work: they quickly select reagents for reactions, make correct observations and conclusions. Research work can help students decide on the choice of a profession where the main focus is working with chemicals.

Research work requires a lot of time, and mostly takes place outside school hours. Students in grades 9-10 annuallyparticipate in the school scientific-practical conference, with some works they speak at the municipal scientific-practical conference. In 2016, a student of grade 9b Ekaterina Berestetskaya spoke at a city conference with the topic "Nutritional supplements and their effect on the human body", the presentation is posted on the website https://sites.google.com/site/gabdrakhmanova5/home/vneklassnaa-rabota/gorodskaa-konferencia

In 2017, 9th grade students Artem Shcheglov with the topic “Adsorption properties of coal” and Denis Skvortsov with the topic “Iron - an element of civilization and life” spoke at the municipal scientific and practical conference and took third place. Appendix 3 presents fragments of Artem Shcheglov's work. Link to presentations for the works https://sites.google.com/site/gabdrakhmanova5/home/issledovatelskaa-rabota/zelezo

reagent

№ test tubes

litmus

NaOH

blue

NaCl

Violet

HCl

red

Task 2

In three numbered tubes under No. 1, No. 2, No. 3 there are solutions of barium chloride, sodium sulfate and potassium carbonate. Recognize substances, compose reaction equations in molecular, full and reduced ionic form.

Work in pairs (filling in the table, compiling reaction equations)

	reagents
Substance formulas	HCl	BaCl2	H2 SO4	№ test tubes
BaCl2			white precipitate
Na2 SO4		white precipitate
K2 CO3	Colorless and odorless gas

One of the substances reacts with the added reagent, while the other two do not. At the same time, we observe that in one of the test tubes the reaction really took place, that is, some external sign of it should be observed - gas evolution, color change, precipitation, etc.

Reaction equations

K2 CO3 +2 HCl → 2 KCl +H2 O+CO2

2K+ +CO3 2- + 2H+ + 2Cl- → 2 K+ + 2Cl- + H2 O+CO2

2 H+ + CO3 2- → H2 O+CO2

Na2 SO4 + BaCl2 → BaSO4 ↓ + 2 NaCl

2 Na+ + SO4 2- + Ba2+ + 2Cl- → BaSO4 ↓ + 2 Na+ + 2Cl-

Ba2+ + SO4 2- → BaSO4 ↓

H2 SO4 + BaCl2 → BaSO4 ↓ + 2 HCl

2H+ + SO4 2- + Ba2+ + 2Cl- → BaSO4 ↓+2H+ + 2Cl-

Ba2+ + SO4 2- → BaSO4 ↓

Task 3

Three numbered tubes contain solutions of sodium, magnesium, and aluminum chlorides. Recognize substances, compose reaction equations in molecular, full and abbreviated form.

Work in pairs (filling in the table, drawing up reaction equations).

Substance formulas

Reagents

№ test tubes

NaOH

Reaction equations

MgCl2 + 2 NaOH → mg( Oh) 2 ↓+ 2 NaCl

mg2+ + 2 Cl- + 2 Na+ + 2 Oh- → mg( Oh) 2 ↓ + 2 Na+ + 2 Cl-

mg2+ + 2 Oh- → mg( Oh) 2 ↓

AlCl3 + 3 NaOH → Al( Oh) 3 ↓ + 3 NaCl

Al3+ +3Cl- + 3 Na+ + 3OH- →Al(OH)3 ↓ + 3 Na+ +3Cl-

Al3+ +3OH- →Al(OH)3 ↓

Al(OH)3 + NaOH → Na

Al(OH)3 + Na+ +OH- → Na+ + -

Appendix 3

(Fragments of work)

Research work in chemistry

"Adsorption properties of coal"

Made by 9th grade student Shcheglov Artem

Introduction

In nature, the phenomenon of absorption of other substances by one substance, called sorption, is widespread. Bodies with a developed surface are capable of absorbing, i.e., adsorbing, gas molecules and liquids from the surrounding volume. The practical significance of the phenomenon of adsorption in human life is very great. Recall at least a gas mask or household filters for water purification. In life, activated carbon is more often used in medicine as an adsorbent.

The relevance of the work :

drawing attention to the study of chemistry with practical side and application of the acquired knowledge in everyday life, the development of interest in obtaining theoretical and practical skills in chemistry: work in the laboratory, work with the Internet to search and transfer information.

aim This work is to study and compare the adsorption capacity of white and black activated carbon.

Tasks set to achieve the goal :

find examples of the practical application of the adsorption capacity of activated carbon in human activity and life.

to study the adsorption capacity of black and white activated carbon;

observe and analyze the phenomenon of adsorption, using activated carbon as an example.

Learn how to use a variety of carbon-containing products without harm to health and what are the possibilities of activated carbon.

For research, I got acquainted with various sources, technical literature, Internet resources, and found out that the phenomenon of adsorption is widely represented and a well-studied phenomenon. Adsorption underlies cleaning, drying, gas separation and other processes. On the basis of adsorption, water is purified and clarified, which is subsequently used for drinking and technical needs. In the theoretical part, I used the materials of technical and historical literature, and for the experiment, I used the textbook for students Analytical Chemistry, Laboratory Workshop.

Research methods used in the work :

Study and selection of material;

Observationand analysis of adsorption phenomena;

Experiment.

Hypothesis

Despite high efficiency white charcoal, most people prefer the proven natural preparation - black activated charcoal.Black activated carbon exhibits better adsorbing properties compared to white activated carbon.

Conclusion

Activated carbon has shown us its adsorption abilities, i.e. absorbent properties.

Why, then, is a small black pill able to absorb various substances so effectively?

As I found out, studying literary sources, the matter is in the special structure of carbon, which is layers of carbon atoms located randomly relative to each other, which is why a space is formed between the layers - pores. These pores give activated carbon its properties - the pores are able to absorb and retain other substances. There are an incredible amount of these. So, the pore area of just 1 gram of activated carbon can reach up to 2000 m2 ! White and black activated carbon are widely used based on their properties.

Conclusion s

Coal - medicine, you need to take following the instructions.

Black activated charcoal is better known and more familiar to students than white.

White coal, despite its synthetic origin, is a better adsorbent.

While studying the literature, he deepened his knowledge on the use of the adsorption capacity of activated carbon in human life. When comparing the adsorption capacity of white and black coal, I found out that black coal absorbs odors better; discolors natural lingonberry syrup. White charcoal is better at decolorizing litmus.

Not all substances are completely adsorbed by activated carbon.

One of the reasons that these substances remained in solution and the color did not change may be that the sizes of the molecules of these substances are larger than the sizes of the pores of the adsorbent.

The proposed hypothesis was partially confirmed.