School studies in chemistry. Chemistry Research

Work stages: Review and analysis of labels on products of several manufacturers of Tide, Tide and Dosia, Dosia laundry detergents, study of the composition of Head, Head & Shoulders, Shoulders, Sebosol shampoos, baby cream, children's "Johnsons baby" oils on their labels. The study of information on the packaging; View commercials of washing powder "Tide", "Tide" and "Dosia". "Dosia". Evaluation of the reliability of advertising with the help of experience from the standpoint of chemistry; Drawing up tables.

RESEARCH ACHIEVEMENTS: I HAVE MADE THE PURPOSE OF CHECKING THE TRUST OF ADVERTISING OF WASHING POWDERS. H WITH ATEM TO STUDY COMPOSITIONS OF WASHING POWDERS, CHILDREN'S CREAM AND OIL, SHAMPOOS. Problem solving: For the experience, I chose the advertising of laundry detergents "TIDE" and "DOSIA", children's cream, oil "Johnsons baby", shampoos "Head & Shoulders", "Sebozol".

ABOUT THE WRITING RESEARCH THAT I SHOULD HAVE. 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 four stained fabric spots and soak in "TIDE" and "DOSIA". Take four stained fabric spots and soak in "TIDE" and "DOSIA". Analyze the results obtained (assessed the degree of purity). Analyze the results obtained (assessed the degree of purity). The results of the study are in the table. The results of the study are in the table.

I STAGE. P ROSMOTR AND ANALYSIS OF LABELS ON PRODUCTS. Review and analysis of labels on products of several manufacturers of Tide and Dosia laundry detergents, studying the composition of Head & Shoulders, Sebosol shampoos, baby cream, baby oil “” according to their labels. Exploring information on the packaging. Review and analysis of labels on products of several manufacturers of Tide and Dosia laundry detergents, study of the composition of Head & Shoulders, Sebosol shampoos, baby cream, Johnsons baby baby oil by their labels. Exploring 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, optical enzymes bleach optical bleach 5-15% anionic surfactant 15-30% components water-softening oxygen-containing bleach less than 5% non-ionic surfactant enzymes anti-foam flavoring

WITH LEAVE SHAMPOO: Water (H2O) Water (H2O) Ammonium Lauryl Sulfate (C12H29NO4S) Ammonium Lauryl Sulfate (C12H29NO4S) Sodium Chloride (NaCl) Sodium Chloride (NaCl) Glycol Distearate Glycol Distearate Zinc Sodium Actime Glycol Distearate narant, and Ian nectone, I am using zinc nitrate, zinc nitrate, zinc nitrate, zinc nitrate, zinc nitrate, zinc nitrate, zinc nitrate, zinc nitrate, zinc nitrate, zinc nitrate, zinc nitrate, zinc nitrate, zinc nitrate, zinc nitrate, zinc nitrate, zinc nitrate; 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”

FROM OIL AND CREAM BOTTOM: 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 Mascid Oil Mascid Oil Mascid Oil Mascid Oil Mascid Oil Mascid Oil Mascid Oil Mascid Oil Mascid Oil Mascid Oil Mascidum Oil Calendula Flowers Oil Extract Calendula Flowers Aloe Vera Gel Aloe Vera Gel CO2 Extract CO2 Chamomile Extract “Johnsons baby” “Baby Cream”

CONCLUSION: We do not deny the need for advertising and its important role in the life of a modern person, 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 television screens, from numerous posters. leaflets and brochures. Reading any ad, try to find out if its content does not contradict the laws or the concept of the natural sciences that we study in school.

Student research in chemistry

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

"MBOU school №5" Usinsk Komi Republic

Doubting, we begin to explore,

and exploring, we find the truth.
Pierre Abelard

Introduction

One of the main functions of the teacher is to learn and develop the personality of the student. Of particular importance is the organization of 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 in our school.

Purpose research work is the education of the curious, actively exploring the world, mastering 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 student communication and creativity;

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

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

use the experience of students to obtain new knowledge;

development of the ability to work independently with a variety of information.

Relevance of research work:

the search for the greatest efficiency between the trends of the innovative educational process and the traditional technologies of teaching students;

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 in chemistry classes

In organizing research, theoretical training is required, which students receive in traditional classes on the primary consolidation of knowledge.

The elements of research work are learned in chemistry classes, but various problems arise as the students present very vaguely the research methods, work stages, and presentation of the results of their research work. It is difficult for them to choose sources of information for the topic, generate ideas, find solutions to problems, analyze, compare, make generalizations and conclusions, correlate what has been achieved with previously set goals and objectives.When students are theoretically trained, they should be used inrockywith elements of research and study lessons. To stimulate interest in research activities in chemistry lessons, it is necessary to create a situation of success.

Lessons with research elements.

Students work out in a lesson the individual training techniques that make up the research activity.. Whateverstudents are encouraged to conduct research. It is required to form an idea about the subject and object of research, hypothesis, to show ways to test hypotheses. Algorithm of research students can be offered by the example of a simple problem problem with chemical content. For example, “What should be the properties of an oxide and a hydroxide of an element with atomic number 13?” (Appendix 1). After completing the work, students can offer independent research on the problem: “What properties does the hydroxide of a chemical element have if the electronic structure of the atom is expressed by the scheme: 2e; 8e; 5e? The content of the elements of research activity distinguishes various types of lessons: lessons on choosing a topic and method of research, working with sources of information, lessons with conducting an experiment, listening to messages, defending abstracts, etc.

In the development of student research skills, the role of problem-based learning is very important. Problem situation encourages students to think activities (analysis, synthesis, synthesis, specification, etc.) When considering the topic "Corrosion of metals", you can create a problem situation. The child gives a message in which he talks about the dangers of corrosion. The speaker aims to give a general idea of the 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 throughout the world is lost from it every year), but also indirect: metal structures (cars, roofs, monuments, bridges) are destroyed.” We define the problem that should be solved in the lesson: how to protect metals from corrosion? Students propose and justify methods to protect metals from corrosion.

A chemical experiment is one of the methods for the formation and development of students' research skills. The experiment in the classroom 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 a lesson, you can conduct laboratory experience and determine the medium of salt solutions using universal indicator paper. Observations can be recorded in a table.

After conducting the experiment together with the students, we put forward the problem. Salts are regarded as the result of a neutralization reaction. Why salt solutions have different environments? Based on the known knowledge of 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.

Study lesson

In the lesson-study, students learn the methodology of scientific research, establish the stages of scientific knowledge. Students master their research knowledge and skills in stages, gradually increasing the degree of student autonomy in their research training activities..

At the research lessons, various forms of student learning are used: individual, group, steam room, collective. Preference is given to work in groups of 2-4 people, since work in a group contributes to the formation of communication OUUN. To avoid the drawbacks of group work (conflicts, “hiding behind other people's backs,” etc.), the rules of group work are developed and used..

Practical lesson

In the workshops, students also work in groups. Each group of 2-3 people receives an experimental task, which 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 existing experience, the following structure of lesson-workshops can be proposed:

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

Updating the core knowledge and skills of students;

Motivation of students learning activities;

Acquaintance of students with the instruction;

Selection of necessary didactic materials, teaching aids and equipment;

Student performance under the guidance of a teacher;

Compilation of a report;

Discussion and theoretical interpretation of the results obtained.

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 grade 11, 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 knowledge: to teach them to ask questions and try to find answers to them, to be able to explain the results, to make sound conclusions. The introduction of a research approach helps to increase the motivation of learning activities in teaching chemistry.

Research work at school can be varied. The skills of research work in chemistry lessons, students receive in practical work, which combines a variety of tasks: experimental tasks, design tasks that require theoretical preparation for work, and reflect the main stages of research activities.

When solving experimental problems, students see the connection of chemistry with life, which contributes to the development of interest in the study of the subject, as well as to prepare them for the conscious performance of practical work (Appendix 2). Student research is carried out both in chemistry classes and in extracurricular time.

Extracurricular research +

- identification of talented and gifted students

Many students are able to engage in research, and especially research activities. It is important to be able to identify talented and capable students. It must be borne in mind that the student’s overall academic performance is not the main indicator of his real abilities. It is more difficult to identify students' readiness for this type of activity. Required to find a student who is interested in it, and who will bring the work to the end.

In the classroom, such children are noticeable in the performance of practical and laboratory work, drafting projects, making presentations. When checking such tasks, it is necessary to pay attention to the creative approach to the performance of 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 speech, it is proposed to answer several questions aimed at identifying attitudes towards this type of activity.

When analyzing such speeches, one should pay attention to those students who have 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 emphasize performance and responsibility of the student. How to interest a student? For this you can use several techniques. First, to convince that participation in research work is useful in later life, outside of school. Secondly, knowing that adolescents strive to somehow stand out, to be not like the majority, participation in research work will allow them to feel their particular position among classmates. Third, create an atmosphere of competition.

- work with literature

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

- practical part of the work

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

In carrying out 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.

- performance at scientific conferences

Scientific and practical student conferences are held annually in the school. The success of a speech at a scientific-practical conference depends on how well and confidently 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 work. Protection of the work will be effective when the student is fluent in information, oriented in all parts of the work done, knows the terms, has the skills of public speaking, is well prepared for speaking at the conference. A student engaged in research shows considerable autonomy at all stages of work. In such children their cognitive activity increases and, as a rule, the quality of knowledge on the subject improves. Learned experience and student learning skillsaffect the quality of the experiments performed in practical work: they quickly select reagents for carrying out reactions, make the correct observations and conclusions. Research work can help students determine the choice of profession, where the main focus is to work with chemicals.

Research work takes a lot of time, and mostly happens after hours. Grade 9-10 students annuallyparticipate in the school scientific-practical conference, with some works appear at the municipal scientific-practical conference. In 2016, Ekaterina Berestetskaya, a student of grade 9b, spoke at the city conference with the theme “Nutritional Supplements and Their Effects on the Human Body”, the presentation is posted on the website https://sites.google.com/site/gabdrakhmanova5/home/vneklassnaa-rabota/gorodskaa-konferencia

In 2017, students of class 9g Shteglov Artem with the theme “Adsorption properties of coal” and Skvortsov Denis with the theme “Iron is an element of civilization and life” spoke at the municipal scientific-practical conference and took the third place. Appendix 3 presents fragments of the work of Artyom Scheglov. Link to presentations to the work https://sites.google.com/site/gabdrakhmanova5/home/issledovatelskaa-rabota/zelezo

reagent

№ test tubes

litmus

NaOH

blue

NaCl

violet

HCl

red

Task 2

In the three numbered tubes under №1, №2, №3 there are solutions of barium chloride, sodium sulfate and potassium carbonate. Recognize substances, make up the reaction equations in molecular, complete and abbreviated ionic form.

Work in pairs (filling in the table, making the equations of reactions)

	reagents
Formulas of substances	HCl	BaCl2	H2 SO4	№ test tubes
BaCl2			White precipitate
Na2 SO4		White precipitate
K2 CO3	Gas without color and smell

One of the substances reacts with the added reagent, and the other two do not. At the same time, we observe that in one of the test tubes the reaction did indeed take place, that is, there should be some external sign of it — gas evolution, color change, precipitation, etc.

Reaction equations

K2 CO3 +2 HCl → 2 KCl + H2 O + CO2

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

2 H+ + CO3 2- → H2 O + CO2

Na2 SO4 + BaCl2 → BaSO4 ↓ + 2 NaCl

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

Ba2+ + SO4 2- → BaSO4 ↓

H2 SO4 + BaCl2 → BaSO4 ↓ + 2 HCl

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

Ba2+ + SO4 2- → BaSO4 ↓

Task 3

In the three numbered tubes are solutions of sodium chloride, magnesium, aluminum. Recognize substances, formulate reactions in molecular, complete and abbreviated form.

Work in pairs (filling in the table, making up the equations of reactions).

Formulas of substances

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

Al3+ +3 OH- → Al (OH)3 ↓

Al (OH)3 + NaOH → Na

Al (OH)3 + Na+ + OH- → Na+ + -

Appendix 3

(Fragments of work)

Chemistry Research

"Adsorption properties of coal"

Fulfilled student 9g class Shcheglov Artem

Introduction

In nature, the phenomenon of absorption by one substance of other substances, called sorption, is widespread. The bodies with a developed surface are able to absorb, i.e., adsorb, a liquid from the surrounding volume of a gas molecule. The practical significance of the phenomenon of adsorption in human life is very large. Recall at least a gas mask or household filters for water treatment. In life, activated carbon is more often used and in medicine as an adsorbent.

Relevance of the work :

drawing attention to the study of chemistry from a practical point of view and applying the knowledge gained in everyday life; developing interest in obtaining theoretical and practical skills in chemistry: working in a laboratory, working with the Internet to search for and transmit information.

Purpose This work is the study and comparison of 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 activity and in human life.

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

observe and analyze the phenomenon of adsorption, on the example of activated carbon.

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 well studied phenomenon. Adsorption underlies the cleaning, drying, separation of gases 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 technical and historical literature materials, and for the experiment I used the textbook for students Analytical Chemistry, Laboratory Workshop.

Research methods that were used in the work :

Study and selection of material;

Observationand analysis of adsorption phenomena;

Experiment.

Hypothesis

Despite the high efficacy of white coal, most people give their preference to a proven natural product - black activated carbon.Black activated carbon exhibits better adsorbing properties compared to white activated carbon.

Conclusion

Activated carbon showed us its adsorption capacity, i.e. absorbing properties.

Why, then, can a small black tablet absorb various substances so effectively?

Studying literary sources, I found out that the matter is in the special structure of carbon, which is layers of carbon atoms located randomly relative to each other, because of which a space — pores — is formed between the layers. These pores and give activated carbon its properties - pores are able to absorb and hold other substances in themselves. Such an incredible amount of time. Thus, the pore area of only 1 gram of activated carbon can reach up to 2000m2 ! White and black activated carbon is widely used based on its properties.

Conclusion s

Coal is a drug, you need to take following the instructions.

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

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

When studying the literature, he deepened his knowledge about 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; discolor the natural lingonberry syrup. White coal is better discolored 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, it may be that the sizes of the molecules of these substances are larger than the pore sizes of the adsorbent.

The hypothesis was partially confirmed.

Research

TOPIC: Dishwashing detergents and their properties. Effect of detergents on the corrosion of metals.

Introduction p. 2-3

Chapter 1. General information on dishwashing detergent page 4-5

1.1 Means for washing dishes page 4

1.2 Composition of dishwashing detergent page 4-5

Chapter 2. Diagnostics of detergents for dishes p. 6-8

2.1. Diagnosis of the use of dishwashing detergent p.6

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

2.3. Physico - chemical properties of dishwashing detergents. pp. 7-8

2.4. The influence of detergent solutions for dishes on page 8

the course of corrosion of iron objects.

Conclusion page 9

References page 10

Appendix page 10

Introduction

The twenty first century is a time when information became the foundation on which all spheres of human life are based. Therefore, each person must be sure that the information he owns is reliable and will not bring spiritual and physical damage to him and others. The flow of information reaches us from everywhere, but the main source is the media. And often even an educated and sophisticated 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." Due to the active advertising policy of manufacturers, today almost every family uses special means for washing dishes. So, scientists estimate that the Russian family of 4 people washes about 5 tons of dirty dishes every year! The first MCs appeared more than 5,000 years ago in the Middle East. But their role in our lives has not changed yet. MS is currently used to remove various types of dirt: stains on clothes, rust, dirty dishes, etc.

In terms of its composition, dishwashing detergents are close to shampoos and shower gels. That is, to hygiene products. And they have special security requirements. All this is good, however, dishwashing detergents are listed as household chemicals. This means that they do not need a hygienic certificate guaranteeing safety. The requirements for the toilet cleaner, which are the same for dishes. Manufacturers may subject their products to safety testing, but voluntarily. Chemists acknowledge that this certificate only guarantees that at the time of use you will not be poisoned or ruin your skin. But what happens over time in the body, in which residues of detergent constantly fall, such studies have not been carried out.

With the constant increase in the number of new chemicals entering the circulation, actual problem is to study them in order to obtain information about the potential hazard of substances and the development of preventive measures involving the prevention of adverse effects on the human body and the environment. Among the complex of environmental factors that are subject to hygienic control, household chemical goods (TBH) deserve special attention due to their mass production and use, the variety of components that make up the recipes, as well as possible direct effects on the human body. As you know, after use, all chemicals enter the environment and adversely affect it, but we don’t think about it. Therefore, we decided to devote our work to household chemicals and, having studied the composition of MC for dishes, determine how safe their use is.

We believe that our work is very relevant today. We can not do without the MC, but their use often harms our world. To understand how to deal with the harm done to us by the MS, we must first learn more about them than is reported in the advertisement. We decided to conduct a study in our school in order to identify the means that are in the greatest demand and to analyze what justifies the choice of participants in our study. Saying yes or no to the MS case is every person’s business, but if you follow certain rules, then the health risk will be minimal.

Practical significance The work consists in the fact that the obtained information on the results of the research work can be used to educate the population of the village about the harm of certain detergents, about the negative effect of SMS on human health, on increasing the corrosion of metals from which sanitary engineering is made.

purpose works: to investigate the physicochemical properties of detergents, to investigate the effect of detergents on the corrosion of metals from which sanitary engineering is made.

Tasks :

1. To study the literature on this issue;

2. Identify the most commonly used home-made detergent brands for dishes;

3. Examine the composition, data detergents for dishes using their labels.

4. Investigate the physicochemical properties of detergents;

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

Object of study : liquid dishwashing detergent.

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

Hypothesis: if you have complete information on the composition and properties of detergents, then You can save human health, prevent damage to plumbing, made of iron.

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

Chapter 1. General information about dishwashing detergents

1.1 Dishwashing detergents and their properties

Special dishwashers first appeared in the 1950s. Dishwashing detergents are available in liquid or gel form. Gel-like agents are considered more effective than liquid ones.

The main properties of the tool is its detergency. A big plus means is its ability to effectively deal with oil and grease in cold water, this is achieved through the selection of the optimal surfactant composition.

Another important feature of the dishwashing liquid is its gentle effect on the skin of the hands. It is worth noting that the statements of manufacturers that the pH level of their products is 5.5, in no way can guarantee the absence of irritation, especially in people prone to allergies. Therefore, during washing dishes skin needs protection. The tool should contain softening components and you should not forget that hands can be protected from the harmful effects of the tool with the help of ordinary rubber gloves.

Much about the dishwashing detergent can tell its composition.

1.2 Composition dishwashing detergent

The basis of the detergent are surfactants. It is they who determine its washing ability.

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

The principal difference is that nonionic surfactants are not subject to electrolytic dissociation, i.e. they do not break up in water into positively and negatively charged ions; when interacting with water, ionic surfactants decompose into ions, some of which have adsorption (surface) activity, while 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 in which they are used, exhibit either anionic or cationic properties; therefore, they are called amphoteric or ampholytic. Anionic surfactants - organic acids and their salts. Cationic - bases, usually amines, and their salts. In the global production of surfactants, most of the anionic substances.

Synthetic detergents necessarily contain a number of excipients that improve their detergency. The composition of the detergent compositions sometimes include alkaline salts of weak inorganic acids (sodium carbonate and sodium bicarbonate, sodium silicates, phosphates of different composition), neutral salts (sodium chloride), salts of peroxide acids with whitening and disinfectant properties (perborate and sodium percarbonate). It is these chemicals that enter into chemical reactions with the metals from which plumbing is made, and under the action of these substances and corrosion of metals occurs. Corrosion causes billions in losses annually, and the resolution of this problem is an important task. The main damage caused by corrosion, is not in the loss of the metal itself, but in the huge cost of products destroyed by corrosion. That is why the annual losses from it in industrialized countries are so great.

An important role is played by organic components of surfactants: carboxymethylcellulose, which prevents the redeposition of contaminants from the washing solution on 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, foam stabilizers.

In many detergents add aromatic substances (fragrances), designed to eliminate odors and give the washed surface a fresh aroma. True, the smell of apple, lemon or, for example, wild berries does not mean the presence of extracts of the above mentioned fruits in this product.

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

Herbal extracts soften the skin, have a calming effect, relieve irritation, which can be caused by individual components of surfactants (such action has, for example, milk "aloe vera"). But even with all the undoubted merits of these supplements, it is impossible to guarantee your skin complete safety.

Chapter 2. Diagnostics of detergents for dishes

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

Survey data shows that Fairy is the most popular medium. It is used by 19 people from the number of respondents, which is 38%. Next, in descending popularity, go: "AOC" - 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.

For the study of the composition, properties, features of the use of detergents for dishes, labels of the products indicated when questioning users were studied. As a rule, no one reads the instructions for washing dishes, but this does not relieve the manufacturer from having to put this information on the label.

These studies 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

18months

18 months

24 months

Composition

5-15% anionic and non-ionic surfactants, fragrance, preservative, citroneplol, limonene and linalool.

5-15% anionic and non-ionic surfactants, ethylenediaminetetraacetic acid salt, flavoring agents, preservatives

anionic and non-ionic surfactants, sodium chloride, citric acid, preservative, perfume composition, citric acid

Water, anionic and non-ionic surfactants, ethylenediaminetetraacetic acid salt, flavoring agents, preservatives,

Water, surfactant,

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

apply a small amount on a wet sponge

A few drops of the product drip onto a wet sponge.

Apply a small amount to a wet sponge.

6. Precautions

In case of contact with eyes, rinse with water.

Keep out of the reach of children

Protect from sunlight. Keep away from heaters. Keep out of the reach of children. In case of contact with eyes, rinse with water.

Keep away from children, avoid contact with eyes.

These tables allow you to do the following findings:

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

“Fairy”, “AOC” can be attributed to more expensive means, “Myth”, “SORTI” and “Drop” are cheaper means.

The shelf life of all funds is almost the same.

The main component of MS are surfactants.

in addition to surfactants in the composition of detergents there are 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 product required for use. Only it says “put a small amount on a sponge or on dishes” or “drop a few drops ...”.

Virtually all means except "Fairy"Contain a warning:" Keep out of the reach of children "and describe the actions when the product gets into the eyes.

Much attention is paid on the MC label to advertising data: manufacturers indicate that all means effectively remove fat, not only in hot but also in cold water, are easily washed off with water, without leaving stains. On the label means "Fairy»Indicated that complies with the standard of the Russian Federation on washability from dishes.

2.3. Physico - chemical properties of dishwashing detergents.

Test 1: Study of the pH of the solution.

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

To determine the pH of the solution, we took a 0.1% solution of each agent, examined it with a device for determining the pH of solutions. The results of the experiment are shown in table 2. Conclusion: All remedies are pH neutral.

Table 2:

Chemical properties of dishwashing detergents.

Indicator

Fairy

AOC

Myth

Sorti

A drop

1. pH of solution

7,68

7,7

6,0

Content

phosphate

Experience 2 : Phosphates in dishwashing detergents .

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

0.1% solution of each agent was tested with silver nitrate. There was no yellow or white precipitation in the tubes. A yellow precipitate indicates the presence of phosphate ions in the samples (Ag 3 PO 4), 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 in detergents are not detected.

2.4. Influence of detergent solutions for dishes on the course of processes

corrosion of iron objects.

When disposing, the used detergent solutions for dishes are in direct contact with metal sewage pipes, and when washed with metal dishes.

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. Tap water was used as a control sample. The experiment was conducted with three repetitions.

On the first day, rust appeared on the nails in the following media: “JSCS", "a drop Sorti". On the second day, a rust bloom appeared in a test tube with tap water and on a nail dipped in "Fairy» . In the “MYTH” tool, rust appeared in the test tube on the third day, while the nail remained clean. In the following days, the buildup of rust on the nails increased, and most quickly in the media: “Fairy"," JSC S", "a drop Sorti". Rust was deposited at the bottom of the tubes - a brown precipitate. By the end of the observation, the height of the sediment was different in test tubes: “AOS"- 10mm," Fairy"-7mm," a drop Sorti"- 9mm," MYTH "- 4mm," Drop "-9 mm, water - 3mm.

Conclusion: All investigated solutions of dishwashing detergents contribute to the corrosion of iron objects, and therefore have a negative effect on sewage pipes and metal dishes.

Final part

Findings:

The most popular among the population are the means: “Fairy”,

« AOS.

Labels of detergents contains a large amount of advertising promises,

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

All means are well soluble in water.

4. All funds are neutral.

5. Means do not contain harmful phosphate additives.

6. All investigated solutions of dishwashing detergents contribute to the corrosion of iron objects, and therefore have a negative effect on sewage pipes and metal dishes.

We want to advise you more responsibly to the choice of detergents and not to allow advertisements to deceive themselves. 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 the use of certain detergents affects our environment. We also want to advise you, be careful with detergents and do not forget that they contain ingredients that can cause rashes, chemical burns, irritations and allergies. Always read the precautions written on the back of the package and keep detergents away from children.

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

We hope that in the course of progress safer detergents will be invented, which 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, during class hours, in conversations with pupils and parents, in elective classes in chemistry and ecology.

Literature:

1. Ambramson A.A. and others. Surfactants. Synthesis, analysis, properties,

application. L., 1988.

2.Ashihmina T.Ya. School environmental monitoring. Teaching and methodological manual / Ed. T.Ya. Ashihmina. - M .: Agar, 2000.

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

4. Shpaus Z. Journey to the world of chemistry. M .: "Enlightenment", 1967.

Schwartz A., Peri D. Surface-active substances: their chemistry and technical applications. M., 1953.

Kharlampovich GD et al. Many-sided chemistry. - M .: "Enlightenment", 2004

Applications

Observation: 11/4/15

Observation: 11/10/15