Why does soap lather? Add your price to the Comment database. Practical chemistry Children's games with soap bubbles

Shtanko Daria

A chemistry project for grade 8, “Why does soap wash?” is given.

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1. Relevance of the topic. Goals and objectives………………………………………………………...…….2

2. Introduction………………………………………………………………………………….……..…3

3. History of soap creation. Evolution of soap making…………………….……..…3

Ancient soap……………………………………………………….…..………4

The Middle Ages and soap……………………………………………...……….4

4. Soap making in Russia……………………………………………………………..……….5

5. Soap composition. Why does soap wash……………………………………..……7

6. Chemistry and physics of the washing process……………………………………………………….…...10

7. Making soap with your own hands…………………………………….………12

8. My experiments…………………………………………….…..14

9. Soap production process…………………………………………………………….………18

10. Using soap………………………………………………………….…...20

11. Interesting facts about soap…………………………………………….…….21

12. Conclusion.…………………………………………………………………….……..23

13. List of references……………………………………...…..23

Relevance of the topic. Goals and objectives.

The relevance of my work is determined by the fact that soap is the first hygiene product that every person encounters after birth. We use soap several times a day and don’t even think about how and when it was born. Nowadays, looking at store windows, you can see a wide selection of soap.

Not many products are as popular and widely used in everyday life as soap. It has become very popular to make soap with your own hands as a gift. Soap came to us from ancient times and gradually turned from a luxury into a necessity.

I was interested in what people used before the invention of soap. When was it invented? What does it consist of? Which soap is healthier for the skin and which is more harmful? Where else can you use soap?

And I decided to consider these questions...

Goals and objectives of the work:

Get to know soap. Find out the history of soap
Study the properties and functions of soap, its composition
Explore ways to make soap at home
Make your own soap
Conduct an experiment to determine the hydrogen values of several soap samples. Find out which soap is better for a child and which for an adult
Conduct an experiment and find out in which water soap foams better
Find out where soap can be used in industry.

Introduction

When asking yourself the question of what people cannot do without, many will agree with me: without hygiene products. No crisis will force us not to take a shower or bath. And, of course, the best way to protect yourself from bacteria and viruses is to regularly wash your hands with soap. Over the past hundred years, soap has consistently been considered the best remedy in the fight against disease.

Throughout the day, we touch various objects with our hands, some of which are clean, others not so much. After every touch, millions of microbes remain on our hands, clinging to the oil produced by our sebaceous glands. If microbes are not removed in time, there is a possibility that we, for example, together with food intake, will introduce them into the body. Once in comfortable conditions, microbes will begin to multiply and cause disease.

Each of us knows from childhood that washing our hands with soap is necessary in order to kill bacteria. But it turns out that soap does not kill bacteria, but only separates them from the skin of the hands. And they are easily washed off with water. Soap dissolves all substances stuck to the skin. What processes occur during this? What is soap made of and why does it wash? I decided to study these questions.

The history of soap creation. The evolution of soap making.

The history of soap goes back about 6 thousand years, but even before its appearance, people tried to cleanse their bodies using various means. For example, the ancient Greeks of Homer's time wiped their bodies with fine sand brought from the banks of the Nile, and the ancient Egyptians washed themselves with beeswax dissolved in water. Wild Gallic tribes made a special ointment from beech tree ash and tallow, and the Scythians ground cypress and cedar wood into powder, adding water and incense to it, rubbing the body with this mixture and scraping it off along with the dirt.

Scientists are still arguing about where the first soap appeared, and which people became the founders of soap making, leaning toward completely different and equally plausible versions.

Ancient soap.

According to one version, the first soap was invented in Sumer, the oldest civilization that existed in the 4th-3rd millennia BC. In particular, archaeologists discovered ancient Sumerian tablets dating back to around 2500 BC. BC, which described a process very similar to making soap: wood ash mixed with water was boiled, and then the fat was melted in it. However, the tablets do not say what this solution was called and, most importantly, what it was used for.

The second version says that the history of soap making began in Ancient Egypt about 6000 years ago. This theory is confirmed by ancient papyri, which describe that soap was made from animal and vegetable fats heated together with alkali salts and soda.

But no matter which version is correct, the first soap in the more or less modern meaning of the word appeared in Ancient Rome. According to legend, even the Latin word “sapo” (“soap”) comes from the name of Mount Sapo in Ancient Rome, where sacrifices were made. When the victim was burned, fat was released, which was mixed with ash from the fires. When it rained, this mass flowed into the Tiber, and residents who washed clothes in the river eventually noticed that thanks to it, everything washed much better. Actually, the English word “soap”, Italian “sapone” and French “savon” came from the word “sapo”.

Middle Ages and soap.

With the advent of the Middle Ages in Europe, due attention was completely stopped being paid to cleanliness and personal hygiene. Soap was a fairly valuable product that was available only to two upper classes: the nobility and the clergy. Even the Queen of Spain, Isabella of Castile, admitted that she used soap only twice in her life: at birth and before her wedding.

Soap production developed in England: there were several large soap factories here, and the attitude towards this craft was very serious. It was in England that the first patent for the production of soap was issued - this happened in 1662.

Also, French Marseille became one of the main soap-making centers due to access to such raw materials for soap making as olive oil and soda. And fragrant oils for soap were delivered from Provence. Also, soap making began to actively develop in Greece, Spain and Italy.

Soap making technology really improved, and the widespread construction of soap factories began only in the 17th century.

Only at the turn of the 18th and 19th centuries. The chemical nature of fats was clarified and clarity was brought into the reaction of their saponification. In 1779, the Swedish chemist Scheele showed that the reaction of olive oil with lead oxide and water produced a sweet and water-soluble substance. A decisive step towards studying the chemical nature of fats was taken by the French chemist Chevrel. He discovered stearic, palmitic and oleic acids as products of the decomposition of fats when they are saponified with water and alkalis. The sweet substance obtained by Scheele was named glycerin by Chevreul. Forty years later, Berthelot established the nature of glycerol and explained the chemical structure of fats.

Naturally, the evolution of soap making did not stop there: production technologies developed, equipment was improved, and new ingredients were added.

Soap making in Russia.

Despite the fact that European countries mainly borrowed soap-making methods from each other, in Russia it developed in its own, separate way. Initially, this craft was not even called “soap making”, but “potash making” - after the name of the substance that played the role of a kind of soap. Production consisted of burning felled trees in huge cauldrons right in the forest, and brewing the resulting ash, making lye from it, from which, when evaporated, this same potash was obtained.

Potash making very quickly became an incredibly popular and profitable craft: it became one of the main export products, and entire villages were engaged in it. But such popularity of potash led to massive deforestation, which stopped only after the Frenchman Nicolas Leblanc invented a factory method for producing soda from salt - a new and cheaper alkaline material for soap production.

Soap making in Russia reached an industrial level under Peter I, who even ordered the plants that make up soap to be grown in the fields. But the first real soap factories appeared in Russia only in the 18th century. At the same time, for cosmetic and hygienic purposes, soap was available only to nobles - peasants still washed and washed with lye.

French perfumer Henri Brocard was one of the first to open a branch of French perfume production in Russia. A talented perfumer turned his modest production into a whole factory. Moreover, Brocard’s popularity was associated not only with the perfumes he produced, but also with the production of “folk” soap for all segments of the population, costing 1 kopeck. Another discovery of Brocard was the interesting appearance of the soap - for example, he produced “Cucumber” soap, which really looked like a real vegetable of the same name

In 1839, Emperor Nicholas I ordered the establishment of a Society for the production of stearin candles, olein and soap. Production began that same year by the St. Petersburg Nevsky Plant. And in 1840, the famous and very popular cosmetic line “Nevskaya Cosmetics” began to be produced in pre-revolutionary Russia. But the main emphasis in production was still on soap making. The equipment was constantly changing, only the most modern equipment and soap-making technologies were used, and the quality of the soap produced was very strictly monitored.

Also one of the oldest Russian enterprises, which survived both the revolution and perestroika, is the Nizhny Novgorod Oil and Fat Plant, which has been producing soap since 1905. This plant is especially famous for its laundry soap. Another such enterprise is the Voronezh soap factory "Finist", which was founded in 1891 and is still in operation, producing about 150 types of toilet and laundry soap. By the way, “Finist” is the only pure soap factory in Russia - the rest of the domestic soap producers are either oil and fat factories or perfumery and cosmetics enterprises.

Soap composition. Why does soap wash?

As we said earlier, a mandatory ingredient in ancient soap was ordinary ash. The chemical reaction that occurs between fat and ash is the basis of soap making. It's called saponification. When combined, these substances create a large number of bubbles, the properties of which make it possible to remove dirt.

Of course, today soap making no longer uses ashes and animal fat. They were replaced by natural oils and caustic soda. The soap itself, in its chemical composition, is a sodium or potassium salt of higher fatty (carboxylic) acids, which hydrolyze in an aqueous solution to form acid and alkali.

Modern industry uses salts of higher fatty acids - stearic and palmitic. To produce solid soap, sodium salts of these acids are used, and for liquid soap, potassium salts are used. Today, natural raw materials cannot fully satisfy the needs of the soap industry, so surfactants are used, which are obtained from the processing of coal and petroleum products.

Real soap is made from natural oils (such as olive, coconut or palm) and is more suitable for use on the skin.

Oils are added to soap for a specific purpose. Coconut oil makes a delicious lather. Olive oil is used to make high quality soap. Canola oil (vegetable oil from a special variety of rapeseed bred in Canada; unlike traditional rapeseed oil, it has a low content of substances harmful to the body and is used as food), as well as palm oil supply the skin with nutrients, sunflower oil is used to create cream soap .

Glycerin is a skin soothing and softening agent that makes soap more beneficial. Glycerin is very important in skin care because it is a humectant. Humidifiers absorb moisture from the air, which in turn hydrates your skin. A bar of soap is 1/5 glycerin.

Most often, soap consists of artificial ingredients that give a certain smell or color.

Some soaps contain fragrance oils. These are synthetic chemicals that are mixed to imitate a specific scent. In some cases, they may affect people's chemical sensitivities. The odors in soap should come only from essential oils, which are evaporated or squeezed from plants using a special technology. Essential oils are the aroma-emitting components of plants and are the basis of aromatherapy. They not only give off a pleasant smell, but also have beneficial effects on the body, mind and spirit.

The color of the soap should also be natural. Lavender and rose petals can be used for this purpose. A natural pigment can be used, which, unlike artificial dyes, makes the color rich and natural.

So why does soap still wash? Try taking a greasy plate and washing it under cold running water. You can say with complete confidence that nothing will come of this venture. The only way to remove the sticky oily film is to add a little soap to the water. Consisting of a type of fat itself, it miraculously dissolves any dirt and makes objects sparkling clean.

Soap has one very important quality, namely, it can significantly reduce the surface tension of water, and thereby significantly increase its cleaning properties. Soap foam consists of a huge number of small bubbles, each of which has a water shell. It is these bubbles that are the main secret of soap's cleaning abilities.

The laws of physics and chemistry that ensure the existence of a bubble give it unique physical properties. Because the bubble deceives our eyes. For example, it appears to be round like a ball (which it is when there is only one), but in most cases - namely in foam - it prefers to take the shape of a cube. Behind its thin and fragile appearance, the bottle hides whole treasures. He is one of the wizards of the so-called soft matter, both strong and fluid: he forms a foam that is able to maintain its shape in space, but can also flow when required.

Bubbles reduce the surface tension of water, but at the same time its own cleaning properties are enhanced. Small particles of soot, dust and grease stick to the bubbles, and the foam itself is easily washed off with a stream of water.

At the same time, modern surfactants used for soap making have a molecular composition that interacts with water as efficiently as possible. The surface tension of water is reduced due to the fact that a thin soap “film” covers almost its entire surface.

Chemistry and physics of the washing process

Soap belongs to the category of so-called tensides, and, like many other substances, consists of many small particles - molecules. Tenside molecules have one remarkable feature. One side of the molecule is capable of attracting water, while the other, on the contrary, repels it. Scientists call them hydrophiles and hydrophobes, respectively.

Hydrophobes, in turn, are able to attract fat particles. In the presence of water, all these molecules are immersed in water and, pressing against each other, form a thin flexible film that can close and hold air or other bodies.

When a bar of soap is rubbed with wet hands, an emulsion is formed between water, soap molecules and dirt particles. For molecules, this is a desirable prey. They immediately attack these particles and surround them. Thus, three types of bubbles are formed: “clean” (containing only air), “less pure” (containing air and a small amount of dirt) and “dirty” (containing a lot of dirt and little air). "Less clean" bubbles are not as persistent as "clean" ones and do not last long, while "dirty" bubbles are very small in size and unnoticeable. Therefore, with an equal amount of soap, clean water produces a more stable and abundant foam than dirty water.

The resulting alkali emulsifies, partially decomposes fats and thus releases dirt stuck to the surface. Carboxylic acids with water form foam, which captures dirt particles. Potassium salts are more soluble in water than sodium salts and therefore have stronger cleaning properties.

The hydrophobic portion of the soap penetrates the hydrophobic contaminant, resulting in the surface of each contaminant particle being surrounded by a shell of hydrophilic groups. They interact with polar water molecules. Due to this, the ions of the detergent, along with the contamination, are detached from the surface and pass into the aquatic environment. This is how the contaminated surface is cleaned with a detergent.

Making your own soap

To make soap I needed:

Soap base,

Ethanol,

Food colorings,

Fragrances and cosmetic fragrances,

Cosmetic and essential oils,

Silicone and plastic molds,

Dishes and other auxiliary tools.

Soap "Butterfly"

To make this soap, I took: red dye, “Lilac” flavor, titanium dioxide (for white), a rectangular shape and a “Butterfly” shape.

Performance:

1. Cut and melt the clear soap base.

2. Pour the liquid soap base in half into two glasses. Add titanium dioxide to one glass and red dye to the other.

3. Add Lilac flavoring.

4. Spray the mold with alcohol and pour two colors of soap base into it.

5. Using a wooden stick, make a pattern on the soap, mixing the red and white base.

6. From the remaining red base we make a butterfly and glue it to our soap using the melted base.

7. Let the product cool completely and can be used for its intended purpose.

See photo - Appendix 1.

Soap-scrub “Shell”

For this soap I used brown coloring, hot chocolate flavoring, ground coffee and a shell mold.

Performance:

Cut and melt the opaque soap base.
Pour the liquid soap base in half into two glasses.

3. Add brown dye and ground coffee to one glass with soap base.

3. Add hot chocolate flavoring.

4. Spray the mold with alcohol and pour the soap base into it, alternating layers of white and brown.

5. Let the product cool completely.

See photo - Appendix 2.

Experiments I Conducted

In the course of researching my topic, I did three experiments:

1. Determination of pH value

2. Which soap foams better?

3. Relation of soap types to aggressive environments

First experience

For my experiment, I took six types of soap: glycerin, liquid, handmade soap, Dove, baby bar and baby liquid. I made a soap solution with each type. I lowered an indicator that determines hydrogen levels into all flasks. After coloring the indicators, I checked the colors against the reference PH scale.

From 1 to 4 – acidic environment

5.6 – slightly acidic environment

7 – neutral environment

From 8 to 12 – alkaline environment

When studying the acidity of soap solutions, it was found:

Soap type	pH reading	Wednesday
Glycerin	10,5	alkaline
Liquid		slightly acidic
Handmade soap		slightly acidic
Dove		alkaline
Children's pieces		alkaline
Baby liquid		slightly acidic

See photo - Appendix 3.

Conclusion:

The term pH is a pH value. It allows you to determine whether the environment is acidic, alkaline or neutral. Pure water is neutral, its pH is 7. If the pH is less than seven, it is said to be acidic; if it is more, it is alkaline.

Soaps that have an acidic environment do not lather well and do not remove impurities from the skin well; Soaps that have a slightly alkaline environment (this means that the basis of this soap are palmitate and sodium stearate, which form solutions with a slightly alkaline environment) better remove dirt from the skin.

A high pH value indicates the presence of free alkali in the soap.

Human skin can be: normal, irritable, dry, oily, combination. For each skin type, it is necessary to choose the right soap to care for it.

Normal skin - you can use soap with any solution reaction, because... the skin is not particularly sensitive.
Irritable skin - the soap should be neutral so as not to dry the skin, and without dyes and perfume additives, because some of them may cause allergies. Coconut oil salts are allergenic, so it is better to choose soap of a different composition.
Dry skin - only neutral soap and preferably with moisturizing ingredients (glycerin, petroleum jelly, etc.). It is more correct to replace solid soap with liquid soap, or use special tonics, cosmetic milk, and other products.
For oily skin, alkaline soap will help remove excess sebum.
Combination skin – caring for it is difficult, because... it combines areas with different skin types. You need to select different types of soap to care for certain areas or use special cosmetics.

As a result, I came to the conclusion that for hygienic purposes it is necessary to use only those types of soap that contain a minimum amount of alkali, but different skin types require different pH values. It must be taken into account that the skin of the hands and face is different. To care for facial skin, you should use soap with a lower pH value, and for washing your hands - with a higher one.

Alkali is very harmful for children's skin, so the main difference between baby soap and regular soap is a different pH level. The acidity of a small child's skin reaches 7-8.

Thus, from my experience it is clear that the most suitable for a child from the samples I tested is liquid baby soap and handmade soap with a pH level of 6, and for an adult - liquid soap for adults with a pH level of 5.

Second experience

I took the same soap samples as in the previous experiment. I made two solutions with each sample: one with distilled water, the other with tap water. I foamed each solution. In flasks with distilled water, foam formed faster and lasted longer than in flasks with hard water.

See photo - Appendix 4.

Conclusion:

Analysis of soap samples based on water of varying hardness showed that the quality of the washing ability of soap directly depends on the hardness of the water.

The foaming ability of cleaning solutions is characterized by the volume or height of the foam column, as well as foam resistance. In soft water, soap forms a more abundant and stable foam than in hard water.

According to the data I received, soap solutions exhibit the best foaming properties in distilled water.

According to Rospotrebnadzor, in the village of Upravlencheskiy the total hardness of water is noted at the level of 16 mg-equiv./liter with a standard of 7, therefore the foaming in such water is very low, the soap consumption of the residents of our village is very high. And as a result, we spend more money on detergents than residents of other districts of the city of Samara.

Third experience

Stage 1 .

I took the same soap solutions with distilled water. Hydrochloric acid was added to each flask and the following results were obtained:

Glycerin - a flaky sediment has formed

Liquid - no change

Handmade soap - gel-like sediment

Dove – flocculent sediment

Baby lump – flaky sediment

See photo - Appendix 5.

Conclusion: Soaps react with acids: In almost all reactions, stearic acid precipitates in the form of a white amorphous precipitate. There are no visible changes in liquid soap samples.

Stage 2.

I again took the same soap solutions with distilled water. Copper sulfate was added to each flask. Got the following results:

Glycerin - sediment

Liquid - no change

Handmade Soap – Sediment

Dove – blue sediment

Baby lump – blue sediment

Baby liquid – no change

See photo - Appendix 5.

Conclusion:

Soaps react with salts of heavy metals: insoluble salts of higher carboxylic acids are formed.

Stage 3.

Glycerin – “stony” sediment

Liquid - no change

Handmade soap - no change

Dove – white sediment

Baby lump – “rocky” sediment

Baby liquid – no change

See photo - Appendix 5.

Conclusion: When various types of soap were examined for the presence of chloride ions, it was found that the Cl (NaCl) ion was present in every soap. In addition to the fact that NaCl is used due to its ability to attract and bind water molecules, due to the increase in water content in the skin, due to the provision of long-term hydration, due to the reduction of odor, it also has a drying effect, which is bad for the skin and causes discomfort. And when such soap gets into your eyes, it causes a burning sensation.

Soap production process.

The process of industrial soap production includes two main stages: chemical and mechanical. At the first stage, which consists of cooking soap, an aqueous solution of sodium (or potassium) salts of fatty acids or their substitutes is obtained. This production stage is based on the saponification reaction. This is the name given to the hydrolysis of fatty acid esters with alkalis. As a result of this reaction, alkali metal salts and alcohols are obtained.

Unrefined fats undergo special treatment in digesters using caustic alkali (most often caustic soda), resulting in the so-called “soap glue” - a homogeneous viscous liquid that thickens when exposed to low temperatures. It consists of soap and glycerin.

Then the resulting mixture undergoes additional purification: soap cooking is completed by treating the composition with electrolytes - excess alkali or sodium chloride. Under the influence of these substances, the solution stratifies: concentrated soap (“soap core”) appears on the surface, which contains up to 60% fatty acids. Water, glycerin and pollutants collect at the bottom. Often, glycerin undergoes additional purification and is added back to the soap solution or used for other purposes (it is even used in the production of alcoholic beverages and confectionery products).

The soap that is obtained as a result of all these procedures is called “sound”.

This is how laundry soap is produced - purified from protein, coloring and other types of impurities with a high concentration of soap substances. In order to improve the characteristics and reduce the cost of laundry soap, additional fillers are introduced into it: sodium salts, adhesives, starch. When producing various detergent compositions and pastes, crushed sand and/or fatty clays are added to liquid laundry soap, which promotes better mechanical cleaning.

At the second, mechanical, stage of production, the resulting semi-finished product undergoes mechanical processing: cooling, drying, adding various components, finishing and packaging. To do this, the resulting soap core is ground on the rollers of a sawing machine, then the sawn soap is pressed into rectangular pieces. This soap is considered a premium product: the fatty acid content in it increases to 74%. If during production caustic soda is added as an alkali, then the result is solid sodium soap, but if caustic potash is used, then the output is soft or liquid potassium soap.

The water content in toilet soap is reduced to 12% (in laundry soap it reaches 30%), and then perfumes, dyes, bleaches, and moisturizing components are added to it. Soap with moisturizing properties is considered to be a product containing at least 50% coconut or palm oil. Coconut oil foams well and dissolves in water. The higher its content, the more expensive the soap costs. In addition, in expensive products, saponin, which is obtained from soap root, is used to improve foaming. This substance not only forms foam well, but also dissolves well in water.

Depending on the formulation, various flavors, preservatives, fragrances, antioxidants and dyes are added to industrial soap. They give the product an attractive appearance, a pleasant smell, and also increase its shelf life. In some cases, during the production of soap, disinfectants, foaming agents, therapeutic and prophylactic and other additives are added.

Using soap.

Soap plays one role or another in many areas of life and activity of civilized human society:

● its role is essential in preventing the spread of diseases;

● in the textile industry, water-insoluble metal soaps are used to make waterproof fabrics;

● in the metalworking industry, soaps are used to protect metals from corrosion and to lubricate dies when drawing wire;

● in the leather industry, metal soaps are used to make leather waterproof;

● in the rubber industry, petroleum products with emulsified soap are used to produce synthetic rubbers;

● in the cosmetic industry, organic alkali soaps (amines) are used as the main component of many shampoos and creams;

● in the shipbuilding industry, soaps are used as the basis for antifouling coatings and as algae growth inhibitors;

● in the paint and varnish industry, soaps serve as the basis for drying and matting substances;

● Soaps are used as a lubricant in plastic molding and as a disinfectant and cleanser in the food industry.

Interesting facts about soap.

● Before the invention of soap, fat and dirt were removed from the skin using ash and fine river sand.

● To wash clothes, they used lye obtained from processing ash with water.

● The credit for the invention of soap belongs to the Gallic tribes. The galls made an ointment from the tallow and ash of the beech tree, which was used to dye hair and treat skin diseases.

● Our ancestors used soap root (the roots of some plants from which they obtain foam similar to soap), which they used to wash and wash. There was no soap in the form in which it is known now. But there was also no drying of the skin or irritation from chemical additives and fragrances.

● Soap, like cheese and wine, must also ripen. And with age, oddly enough, soap also gets better. “Old” soap is more gentle, foams stronger, and irritates the skin less.

● Surely, many people are tormented by the question: “Can soap be dirty?” No, soap is never dirty. It is very unlikely that any bacteria will live with surfactants. And if you still have doubts (for example, a bar of soap fell on the floor), just hold the soap under running water for a few seconds to wash away the bacteria lying in ambush. But dispensers used to dispense soap in public places can still be dirty. Keep this in mind when dispensing liquid soap and try not to touch the dispenser after washing your hands.

● “Exchange an awl for soap”, “Soap opera”, “I’ll soap my neck!”... how many times have we heard or used these expressions ourselves. Where did they come from? And what does soap have to do with it? What else is interesting about such a familiar subject?

For example, “soap your neck.” Now it means to scold, to punish for some offense. But this comes from the fact that at a time when the death penalty was popular, the hanging rope was soaped so that it would slide better.

The expression “soap your neck” in Russian means to scold, beat, or punish someone. But in Japanese, this means admitting that you were wrong and being ready to atone for it at the cost of your life.

And that’s where the expression “exchange an awl for soap” comes from. Previously, the awl was made of iron and to make it glide better, it was lubricated with soap. That is, if you exchange one necessary thing for another necessary thing in your work, it still won’t work.

● In the 1930s, serial programs with simple tear-jerking stories appeared on American radio. They were sponsored by manufacturers of soap and other detergents, since the main audience for these programs were housewives. Therefore, the expression “soap opera” was assigned to radio and subsequently television series.

● French perfumer Henri Brocard was the first to start producing very cheap children's soap, thanks to which peasant children not only became clean, but also learned to read and write - on each package of soap there was one of the letters of the alphabet.

● English pensioner Carol Vaughn has been collecting soap since 1991. Its collection contains samples from almost all countries of the world. And at the moment, Carol has more than 5,000 pieces of a wide variety of soap!

● And of course there is the most expensive soap in the world. This soap is produced by Plank. This soap is called "Cor" and costs $1041 per kilogram. This cost is due to its composition:

Sericin or silk glue, which is obtained from fresh silk fibers

Chitosan, which is obtained from the shells of red leg crabs

4 types of different collagens

Silver.

Conclusion

I got acquainted with soap and learned the history of its appearance. I studied the properties and functions of soap, its composition. I made my own soap. I conducted several experiments with different samples of soap. Determined the hydrogen values of several types of soap. I found out which soap is better for a child and which for an adult. I found out in what water soap foams better and where soap can be used in industry.

Bibliography:

Devyatkin V.V., Lyakhova Yu.M. “Chemistry for the curious, or what you won’t learn about in class” - Yaroslavl: Development Academy: Academy, Academy Holding, 2000.
E.L. Kulikova Evenings of entertaining chemistry - Minsk: “People's Asveta”, 1966.
Scientific and methodological journal “Chemistry at school” - 2004. No. 2, 8, 9.
V. Kornilova, O. Smirnova “Do-it-yourself soap”: AST-Press, 2011.
G.A. Ryazanov “We make soap at home” 2012.
Publishing house "Astrel", 2012

7. Soros educational journal - Moscow, 1999.

8. Internet resources:

There are many different legends about how soap appeared. People used it about six thousand years ago. Back then it was made from plant and animal fats. Over many centuries, its composition, of course, has constantly changed. And the frequently asked question about why soap washes has not disappeared.

The main function of the product is to clean various surfaces from dirt. And he does a great job with it. So, why does soap wash? Let's try to figure it out.

Why does soap wash? What is his secret?

Let's figure it out. So why does soap wash? The secret of it, like other detergents that belong to surfactants, is to reduce this and enhance its cleaning properties. Soap foam consists of a huge number of soap bubbles with a water shell. Particles of soot, dust and dirt stick to these same bubbles. And the foam is very easily washed off under running water.

Surfactants (more precisely, their molecules) are located on the boundary surface so that hydrophilic groups are directed directly into the water, and hydrophobic ones, on the contrary, are pushed out of it. Thus, the surface of the water is covered with a kind of fence consisting of the above molecules.

This water surface has lower surface tension. This, in turn, helps to completely and quickly wet contaminated surfaces. The particle coated with surfactants is easily separated from the fabric and goes into solution.

In general, soap particles have enveloping properties that result in the formation of emulsions of a variety of contaminants and prevent them from re-depositing on surfaces. They hold insoluble particles in suspension. That is why they are so easily removed with water.

Excellent effect at low cost

However, for most people it is not so important why soap washes. The main thing is that a person is accustomed to cleanliness and accuracy. In principle, in order to get rid of dirt, the most ordinary soap is enough for him. Achieving an excellent effect at a low cost, of course, you can remain satisfied with such a product. The action, as mentioned above, is based on lowering the surface tension of water and strengthening the detergent.

It's a matter of composition

Let us pay attention to one more point. The question of why can be answered directly by its composition. The fact is that it contains sodium stearate, a substance that can dissolve sebum that forms on the surface of the skin. In addition, adhered dirt is washed off. The more alkaline reaction occurs, the better the dirt is removed. Although due to the alkali, the skin noticeably dries out. That’s why manufacturers add all sorts of additives to soap that soften it and give it color and smell. Think, for example, about glycerin. It allows you to achieve a softening effect. Some other additives actually allow the soap to become medicinal. Today the choice is quite large - you can easily choose exactly what you need.

Better than other substances

And finally. Why is soap better than other detergents? Take a simple soot in your hands. Try to wash it. Will not work. Add soap and your hands will immediately become clean. The secret lies in the soap suds. More precisely, in her small, nimble bubbles. It contains natural fat and, when combined, they create a soap mass containing a large number of bubbles, to which particles of dirt stick and are washed off with water.

In general, soap cleans hands and various surfaces much better than other products. Its composition and properties make it possible to cope with all kinds of contaminants without much difficulty. At the same time, you don’t have to worry at all about high costs.

Description of the presentation by individual slides:

1 slide

Slide description:

Ministry of Education and Science of the Russian Federation Ministry of General Education Institution Secondary School No. 48 Scientific research work “Why does soap lather?” Kopeysky urban district 2010 Completed by: Vladislav Kretov, Natasha Suvorova, students of grade 3B. Slide *

2 slide

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It is necessary, it is necessary to wash in the mornings and evenings, And to unclean chimney sweeps - Shame and disgrace! Shame and disgrace! Long live the fragrant soap, And the fluffy towel, And the tooth powder, And the thick comb! Let's wash, splash, swim, dive, tumble in a tub, in a trough, in a tub, in a river, in a stream, in the ocean, and in a bath, and in a bathhouse, always and everywhere. Korney Chukovsky Slide *

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What is unclear should be clarified. What is difficult to create should be done with the greatest perseverance. Confucius Slide *

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In the course of our work, we studied and researched: -the history of soap; -how soap and its composition “work”; -types of soap; - How soap is used nowadays; -how soap is made at home; -conducted an experiment on making soap at home. Slide *

5 slide

Slide description:

Our research work is devoted to the topic "Soap". Hypothesis: “Why soap is an important part of personal hygiene and good health. How did it happen that this product took such an important place in our lives?” Relevance of the topic: It is unlikely that anyone will dispute the enormous importance soap plays for maintaining health and maintaining personal hygiene. People realized that being clean and tidy is a natural human desire, that civilized people simply cannot do without soap. Soap has become a symbol of grace and good manners. Soap is at the height of its fame. The object of the study is Soap and its various types. The subject of the study is Soap and its composition. The purpose of our research is to study the composition of soap, to become familiar with the different types of soap. And understand why soap lathers? The main goal of our work is experience in making soap at home. Slide *

6 slide

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The objectives of our research are: 1. Familiarization with the material on this topic; 2. Get acquainted with the history of the invention of soap; 3. The composition of soap and how it “works”; 4.Study types of soap and their effectiveness; 5.Where is soap used; 6. How soap is made at home; 7. Conduct an experiment on making soap at home. Slide *

7 slide

Slide description:

Once upon a time there was no soap at all - people used only water for washing and washing; later they added ash to the water. Ashes combined with oils are a prototype of soap. And when they combined ash with lime, they invented soap. The word soap, according to legend, comes from the name of Mount Sapo in ancient Rome, where sacrifices were made to the gods. Animal fat released when the victim was burned accumulated and mixed with the wood ash of the fire. The resulting mass was washed away by rain into the clayey soil of the banks of the Tiber River, where residents washed clothes and, they noticed that thanks to this mixture, clothes were washed much easier. Therefore, for a long time the invention of soap was attributed to the Romans Slide *

8 slide

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Archaeologists have found that soap began to be made 6,000 years ago. In ancient times, soap was made from goat, lamb or bovine fat mixed with beech ash. There were three types of it: hard, soft and liquid. They used soap not only for washing, but also for coloring hair. They could not only wash their face, but also dye their hair yellow, pink or red. The Romans learned this from the Gauls, who wore their hair long, and to ensure that it lay well, they lubricated it with vegetable oil, to which they added red earthen dye. When water fell on this mixture, a thick foam formed, thanks to which the hair became clean and fluffy. This is how one of the methods for producing soap was discovered. Slide *

Slide 9

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Soap was known to man before the new era. The earliest written mention of soap in European countries is found in the Roman writer and scientist Pliny the Elder. The development of soap making was facilitated by the availability of raw materials. In Europe, soap making developed in France, Italy, Greece, Spain, and Cyprus, that is, in areas cultivating olive trees. The first German soap factories were founded in the 16th century Slide *

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In 1779, the Swedish chemist Scheele showed that the interaction of olive oil with lead oxide and water produces a water-soluble sweet substance. A decisive step towards studying the chemical nature of fats was taken by the French chemist Chevrel. He discovered stearic, palmitic and oleic acids as products of the decomposition of fats during their saponification with water and alkalis. The sweet substance obtained by Scheele was named glycerin by Chevreul. Forty years later, Berthelot established the nature of glycerin and explained the chemical structure of fats. French chemist Chevreul Swedish chemist Scheele French physiochemist Berthelot Slide *

11 slide

Slide description:

Soap is a product of processing vegetable or animal fats, with the addition of a surfactant (caustic soda or potash). Soap can be toilet (for cleansing the skin and caring for it) and technical (household). Soap can be solid or liquid. Soap contains fats, oils, dyes, perfumes and other additives. The more natural ingredients in the soap, the better it is. If the soap contains synthetic additives, it belongs to a lower quality group Slide *

12 slide

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Types of soap and its effectiveness -Children's hygiene soap -Hygienic antibacterial soap -Exfoliating soap, -Perfume soap -Cosmetic soap -Liquid soap -Iodized soap Slide *

Slide 13

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Natural components included in the soap structure: -Essential oils -Plant extracts -Clay -Healing mud Slide *

Slide 14

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Toilet soap coats the skin with a layer of molecules that remove oil well. Soap at work Slide *

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We conducted a survey among students at our school. 52 students participated in the survey, and we received the following results: The survey included the following questions: Slide * Question No. Question Yes No 1. Is soap production a chemical process? 44 8 2. Does soap play a significant role in maintaining human health? 51 1 3. Is it true that antibacterial soap is considered more hygienic than liquid soap? 29 23 4. Can baby soap be suitable for adults? 37 15 5. Is it possible to make soap at home? 32 20 6. Is it possible to wash your hair with soap? 30 22 7. Do you often wash your face and hands with soap? 43 9 8. What kind of soap do you use? 75% of respondents use solid baby soap

16 slide

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Methods for making soap with your own hands. 1. Cold process method - for people who want to make soap from the very beginning, using a mixture of lye, water, animal and vegetable fats and oils to make soap. This method takes a lot of time and requires skills in working with toxic alkali solutions. 2. Hot processing method - similar to the cold processing process, but heat is required to speed up the process of making soap. The advantage of the hot process is that the soap can be used more or less according to the application. To use this method, you must first master the cold working method. 3. Regrouping method is a method that uses melted soap bars as a base for making soap. 4. Melt and pour method – Similar to the regrouping method, this soap making method is the easiest way for beginners to learn how to make their own soap without mixing lye. The benefit is that you take pre-made natural soap bases and add color, scent and even texture to make your own soap. Knowing how to make natural handmade soap, you can always give wonderful gifts to your loved ones. Slide *

Slide 17

Slide description:

Homemade soap Grind the soap on a grater. It always seemed to me that this was a terribly unpleasant procedure. In fact, it’s not long or difficult at all, and the soap gives curls so beautifully! Slide *

A bubble is primarily air or any other gas enclosed in a thin membrane. If it is foam from soap or washing powders, the shell of the bubble consists of molecules that, if you look at them through a microscope, look like pins with a round head and a long point. The “head” of the molecule is taken from a hydrophilic substance, that is, one that loves water (The word “hydrophilic” comes from the Greek words “hidor” - water and “philia” - love).

The long tail in the soap molecule is borrowed from fat. Fats are “afraid” of water and do not dissolve in it, which is why they are called hydrophobic (from the Greek word “phobos” - fear). In the presence of water, all these pin molecules dip their heads into the water and, pressing against each other, form a thin flexible film that can close and hold air or other bodies. Soap is very rich in these pin molecules - these little rockets that are greedy for everything that is covered with fat.

When a bar of soap is rubbed with wet hands, an emulsion is formed between water, soap pin molecules and dirt particles. For pin molecules, this is coveted prey. They immediately attack these particles and surround them, leaving the heads in contact with water. Thus, three types of bubbles are formed: “clean” (containing only air), “less pure” (containing air and a small amount of dirt) and “dirty” (containing a lot of dirt and little air). “Less clean” bubbles are not as persistent as “clean” ones and do not last long, while “dirty” bubbles are very small in size and unnoticeable. Thus, with the same amount of soap, clean water produces a more stable and abundant foam than dirty water.

And now more seriously about foam and soap

When even a small amount of soap is dissolved in water, it accumulates (adsorbs) at the interface of the water with the surface or fabric being washed. As a result, the adhesion of fat and dirt particles to the fabric is weakened. A thin film of soap on the surface of, for example, a fat drop prevents it from wetting the surface of the fabric. A similar phenomenon can be observed when glass is wetted with water. If the glass is clean, then the droplets spread over its surface, and if it is dirty, then the water does not wet the glass, and the droplets try to retain their shape, i.e. collected in balls.

Adsorbed soap molecules surround the fat droplets and the surface to be washed with a densely filled single (monomolecular) layer, which has high mechanical strength. Soap molecules are tightly bound to each other, and it is very difficult to break the film. Therefore, when washing, films of adsorbed molecules are not destroyed and prevent the re-adhesion of already detached droplets of fat to the surface of the fabric and the merging of the droplets with each other. Particles of dirt and droplets of fat suspended in water are removed along with it.

In the 19th century, the Belgian scientist Joseph Plateau became seriously interested in studying the structure of soap foam. He was the first to notice that in each edge separating the foam polyhedra, three films always converge, no more and no less. It turned out that the films themselves are double, and the ribs between them are channels filled with liquid. The foam settles because the water gradually flows down through the channels.

J. Plateau found a way to use soap films to serve mathematics. He dipped wire frames of various configurations into a soap solution and observed what shape the soap film took. These experiments contributed to the development of spatial geometry (stereometry). Note that due to surface tension, the area of the soap film tends to a minimum. Therefore, soap bubbles, which both children and adults enjoy blowing, have an almost ideal spherical shape.

Foam consists of many bubbles that touch each other. The dodecahedron turned out to be the most advantageous shape of a soap bubble in foam from the point of view of minimizing surface tension. It resembles an angular ball formed from 12 pentagons connected by edges.
By varying the soap ingredients and their proportions, different amounts of foam can be produced. Soaps that leave more lather on the hands and body are in greater commercial demand than those that do not, although their soapiness does not depend on this. And while abundant foam is welcome in products used for personal hygiene, it is completely unnecessary in washing powders for machine washing. This means that additives must be added to the powders to make the bubbles fragile and thereby limit the formation of foam.
This effect can be observed whenever we take a shower or use shampoo. The dirtier our body, the more difficult it is to get a rich lather.

In order to increase the amount of foam, additional vegetable oils (mainly coconut and palm kernel) are added to soaps, or ricinol acid (fatty acid from castor oil), sulforicinol acid, sodium laureth and lauryl sulfates, rosin, lanolin, and spermaceti are added.

Tap water is different in that it usually contains a lot of calcium and magnesium salts. In such water, soap lathers poorly, a coating of sparingly soluble salts forms on the skin, and it becomes unpleasantly tight. All this means that the water is hard.
Water hardness can be partially removed by boiling. You can soften water by adding lactic, tartaric or citric acid, i.e. a spoonful of milk, a spoonful of wine or a little citric acid. These substances form strong complex compounds with calcium and magnesium cations and do not allow them to interact with the fatty acid anions that make up the soap. Even more stable complexes with these cations are formed by ethylenediaminetetraacetic acid (EDTA) or its salt Trilon B (EDTA Na). These substances are usually found in washing and shower gels.
Of course, it is better to use for washing not just softened, but soft natural (rain or snow) water, and, moreover, collected in an area with favorable environmental conditions, and not in a big city, where there is almost more pollution in the atmosphere than in hard water. But you have to be realistic, so after washing your face with tap water, wipe your face with a swab soaked in boiled or even distilled water. This especially applies to those who have dry and very delicate facial skin.

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Slide captions:

MADO "CRR-kindergarten No. 4" Group No. 16 "Rays" Research work: "Soap and soap making" Performed by: Kamalieva Ralina Supervisor: S amigullina G.R.

It all started when my mother bought liquid soap at the store. This interested me. I thought, why is it liquid and not the usual solid? I decided to learn as much as possible about soap. Purpose of the work: To study the history of the origin and process of producing soap, as well as to find out which soap is better: liquid or solid? Objectives: Get acquainted with the history of soap. Find out the composition of the soap. Learn to make soap with your own hands. Find out which soap is better to trust: liquid or solid? Hypothesis: Liquid soap is more trustworthy. Practical significance: Liquid soap is more convenient to use. Research techniques and methods: Observations, literature studies, conversations, Internet resources. Subject of research: soap.

Soap is an integral part of our hygiene. This is a product that people use when they take a bath or wash in the shower to keep their body clean and smell pleasantly fresh.

There are many types of solid soap in our world. For example: household, children's, toilet, cosmetic, etc.

In addition to solid soap, there is also soap in liquid form.

And I wanted to know more about soap. How it is boiled, what people used before the invention of soap, and what its composition is. Now I will try to tell you about it. The history of soap goes back about 6 thousand years. Before the invention of soap, grease and dirt were removed with ash and fine river sand. Various plants were also used to wash hands and bodies, for example, soapwort (saponaria), oak bark.

The discovery of soap as a means of hygienic care is attributed to the famous ancient physician Galen, who lived in the 2nd century AD. In his notes, he left notes about soap, its composition and properties. So he wrote that soap is made from a solution of ash and lime with the addition of fat. In addition, Galen noted that the resulting substance could not only cleanse and soften the skin, but also get rid of dirt on clothing. Over the centuries, people have perfected the process of making soap.

Soap is a cleaning product that we use every day. It comes in different shapes and sizes, and different flavors and colors are added to it. The most important thing in soap is its cleansing properties; it foams well because it contains fatty acids.

What is soap as a substance? Take a glass of water and drop in sunflower oil. The oil will collect on the surface in a single layer. Now let's talk it all out. The oil will break into small droplets.

Add a little soap and mix. As we can see, the soap “ate” the oil droplets. The fact is that soap molecules attacked the droplets of fat, surrounded them, and dissolved them in water.

The same thing happens when we wash dirty and oily hands. Soap molecules surround particles of dirt and grease and dissolve them in water. And the water carries dirt into the sewer. By the way, soap removes not only visible dirt, but also invisible bacteria and germs.

1. From a soap base (special composition for soap production). 2. Soap “from scratch” from fats, oils and alkali (this soap is made in a factory). 3. “Soap from soap” - which I tried to make myself at home: I took baby soap. How to make soap at home?

I grated the soap. Melted it in a water bath.

I laid it out in forms. And this is what I got.

As we already know, soap can be solid and liquid. Which soap should you trust more? Liquid or solid? We all know that we cannot do without soap.

Solid soap - its advantages: - it is quickly washed off, which means it can be used in any situation. -it's cheap. Hard soap - its disadvantages: - it dries quickly. -it dries the skin. - leaves behind a plaque. - germs may remain on it.

Now let's take liquid soap: Its advantages: - it does not dry the skin. -there is a dispenser, which means it is more hygienic. -does not slip out of your hands - foams quickly. - has a persistent aroma - practically anti-allergenic. Disadvantages: - it costs more - it takes a lot of water to wash it off.

And what have we come to? Of course, solid and liquid soap differ little in their composition, but liquid soap has more advantages. Therefore, our hypothesis that liquid soap is better was confirmed. While working on this study, I completed all the assigned tasks. I learned a lot of interesting things and determined the importance of soap in our lives, showed the children in the group and you how you can make soap at home. In the modern world, there are many varieties of soap available on store shelves. We can choose the desired aroma, shape, composition. But handmade soap is more pleasant to receive as a gift. This soap will bring joyful and pleasant moments to a person.

Thank you for your attention.

Preview:

Municipal autonomous preschool educational institution

"Child Development Center - Kindergarten No. 4"

urban district city of Agidel of the Republic of Bashkortostan

Research

on the topic of:

"Soap and soap making"

senior group No. 16

"Rays"

Completed by: Kamalieva Ralina

Head: Samigullina G.R.

It all started when my mother bought liquid soap at the store. This interested me. I thought, why is it liquid and not the usual solid? I decided to learn as much as possible about soap.

Goal of the work – study the history of the origin and process of soap production, as well as find out which soap is better: liquid or solid?

Tasks:

Get acquainted with the history of soap.
Find out the composition of the soap.
Learn to make soap with your own hands.
Find out which soap is better to trust: liquid or solid?

Hypothesis: Liquid soap is more reliable.

Practical significance:Liquid soap is more convenient to use.

Research techniques and methods:Observations, literature studies, conversations, Internet resources.

Subject of study: soap.

Soap is an integral part of our hygiene. This is a product that people use when they take a bath or wash in the shower to keep their body clean and smell pleasantly fresh. There is hardly a house where there is not a single piece of soap!

There are many types of solid soap in our world.

For example: household, children's, toilet, cosmetic, etc. In addition to solid soap, there is also soap in liquid form.

Appendix No. 1

And I wanted to know more about soap. How it is boiled, what people used before the invention of soap, and what its composition is. Now I will try to tell you about it.

The history of soap goes back about 6 thousand years. Before the invention of soap, grease and dirt were removed with ash and fine river sand. Various plants were also used to wash hands and bodies, for example, soapwort (saponaria), oak bark.

The discovery of soap as a means of hygienic care is attributed to the famous ancient physician Galen, who lived in the 2nd century AD.

Appendix No. 2

In his notes, he left notes about soap, its composition and properties. So he wrote that soap is made from a solution of ash and lime with the addition of fat. In addition, Galen noted that the resulting substance could not only cleanse and soften the skin, but also get rid of dirt on clothing. Over the centuries, people have perfected the process of making soap. In Russia, soap production was established by Tsar Peter I. At that time, only rich people used soap, and poor peasants washed themselves with ash. But over time, there were a lot of factories where soap was made and soap became available to everyone.

Soap is a cleaning product that we use every day.

Appendix No. 3

Soap comes in different shapes and sizes, and different flavors and dyes are added to it. The most important thing in soap is its cleansing properties; it foams well because it contains fatty acids.

Practical part:

Experience 1.

What is soap as a substance?

Take a glass of water and drop in sunflower oil. The oil will collect on the surface in a single layer. Now let's talk it all out. The oil will break into small droplets. Now add a little soap and mix. As we can see, the soap “ate” the oil droplets. The fact is that soap molecules attacked the droplets of fat, surrounded them, and dissolved them in water.

Appendix No. 4

How to make soap at home?

1. From a soap base (special composition for soap production).

2. Soap “from scratch” from fats, oils and alkali (this soap is made in a factory).

3. “Soap from soap” - which I tried to make myself at home:

Experience 2

I took baby soap.
Grated it.
Melted it in a water bath.
Added a little honey, oil and glycerin.
Stirred. The finished mass is similar to sour cream.
I added a little dye to make it red.
Added a drop of flavoring.
I laid it out in forms.

Appendix No. 5

And this is what I got.

Appendix No. 6

As we already know, soap can be solid and liquid.

Which soap should you trust more? Liquid or solid?

We all know that we cannot do without soap. It turns out that soap is not so harmless. Let's try to figure it out.

So,

Solid soap - its advantages:

It washes off quickly, which means it can be used in any situation.

It's cheap.

Solid soap - its disadvantages:

It dries quickly.

It dries out the skin.

Leaves behind a residue.

Germs may remain on it.

Appendix No. 7

Now let's take liquid soap:

Its advantages:

It does not dry out the skin.

There is a dispenser, which means it is more hygienic.

Doesn't slip out of your hands - foams quickly.

Has a persistent aroma

Practical anti-allergenic.

Flaws:

It costs more

It takes a lot of water to wash it off.

And what have we come to?

Conclusion :

Of course, solid and liquid soap differ little in their composition, but liquid soap has more advantages. Therefore, our hypothesis that liquid soap is better was confirmed.

Appendix No. 8

While working on this study, I completed all the assigned tasks. I learned a lot of interesting things and determined the importance of soap in our lives, showed the children in the group and you how to make soap at home.

In the modern world, there are many varieties of soap available on store shelves. We can choose the desired aroma, shape, composition. But handmade soap is more pleasant to receive as a gift. This soap will bring joyful and pleasant moments to a person.

Appendix No. 9

List of used literature

"Do it yourself soap"
“We make soap at home”
"Tales of Substance"; edited by Heinrich Ehrlich. – M.: Yauza-press, 2011.-208 p.
“What is everything made of?” Strelnikova L.N.
ru.wikipedia.org›Galen
ru.wikipedia.org›Soap

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