Why does soap wash hands. Why soap is washed? Add your price to the base Comment

There are many legends about how soap came to be. It is known that even six thousand years ago, people used soap made from animal fats and plants. To obtain soap, animal fats were mixed with ash. Of course, the composition of soap has changed significantly over the centuries. But the main function of soap - to clean the surface of dirt, has remained unchanged.

The exact date of the appearance of soap has not been established by scientists. But everyone will agree with the fact that soap appeared a long time ago.

The chemical composition of the soap

Ash along with fat became the prototype of modern soap. When these two components are mixed, chemical reaction, which forms the basis of soap making. As a result of this reaction, soap is obtained. In modern soap production, fat is replaced with natural oils, and ash is replaced with caustic soda. When combined, oils and soda form a mass that contains a large number of bubbles. The shell of each bubble consists of water. Dirt particles stick to bubbles and can be easily washed off with water.

The chemical reaction between ash or soda and fat is called the saponification reaction. This reaction is at the heart of soap making in our time. A chemical composition soap was first installed by a French chemist Michel Eugene Chevreul... It turns out that soap is a sodium salt of a higher fatty (carboxylic) acid.

Each of us in childhood knew 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. The soap dissolves all substances adhering to the skin.

What are the processes taking place in this case?

The composition of modern natural soap includes sodium and potassium salts of higher fatty acids - palmitic C 15 H 31 -COONa and stearic C 17 H 35 -COONa. Solid soap is based on sodium salts of higher carboxylic acids, and liquid soap is based on potassium salts of these acids. But since the production of natural soap requires a large amount of natural raw materials, this raw material was subsequently successfully replaced by surfactants obtained during the processing of petroleum products and coal. This is how synthetic soap and various modern detergents were obtained.

Physics and chemistry of the washing process

How does the soap wash?

The washing process is quite complicated from both physical and chemical points of view.

The chemical formula of the CH3- (CH2) n-COONa soap molecule. It is known that hydrophilicity is the ability of a substance to interact with water at the molecular level. And hydrophobic substances are substances that cannot interact with water. So, the COONa group ensures the hydrophilicity of the soap molecule. Thanks to this group, the soap is water-soluble. A CH3- (CH2) n is a long hydrocarbon radical that is hydrophobic. This radical can contain up to 12 carbon atoms.

Soap, like other detergents, reduces the surface tension of the water by improving the access of the soap molecules to the surface being washed. During the washing process, soap bubbles form on the surface on contact with water. Soap molecules are oriented so that the hydrophilic COONa + groups are directed towards the polar water molecules, that is, inward. They stay in the water. And hydrophobic СН3- (CH2) n are directed upward, towards non-polar particles of dirt. Mud contains grease. And fat is a combination of glycerin with the same fatty acids. CH3- (CH2) n forms a suspension with fat particles, which can be easily removed together with water.

Almost all detergents based on surfactants operate in the same scenario.

Description of the presentation for individual slides:

1 slide

Slide Description:

Ministry of Education and Science Russian Federation Ministry of educational institution Secondary school # 48 Research work "Why does soap wash?" Kopeysk urban district 2010 Completed by: Vladislav Kretov, Natasha Suvorova, 3rd B grade students. Slide *

2 slide

Slide Description:

It is necessary, it is necessary to wash In the mornings and evenings, And to the unclean Chimney sweeps - Shame and disgrace! Shame and disgrace! Long live fragrant soap, And a fluffy towel, And tooth powder, And a thick comb! Let's wash, splash, Swim, dive, somersault 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 bath, Always and everywhere. Roots Chukovsky Slide *

3 slide

Slide Description:

What is unclear should be found out. That which is difficult to create should be done with the greatest perseverance. Confucius Slide *

4 slide

Slide Description:

In the course of work we have studied and researched: - the history of soap; - how the soap "works" and its composition; - types of soap; - How soap is used in our time; - how soap is made at home; - we have had experience in 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 life? " Relevance of the topic: It is unlikely that anyone will dispute how important 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 top of its glory. The object of research is Soap and its various types. The subject of research is Soap and its composition. The purpose of our research is to study the composition of the soap, to get acquainted with different kinds soap. And to understand why soap is washed? The main goal our work is experience in making soap at home. Slide *

6 slide

Slide Description:

The objectives of our research are: 1. Acquaintance with the material on this topic; 2. Get acquainted with the history of the invention of soap; 3. The composition of the soap and how it "works"; 4. To study the types of soap and its effectiveness; 5.Where is the soap used; 6. How soap is made at home; 7. Make experience in making soap at home. Slide *

7 slide

Slide Description:

Once there was no soap at all - for washing and washing people used only water, 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. According to legend, the word soap comes from the name of Mount Sapo in ancient Rome, where sacrifices were made to the gods. The animal fat released during the burning of the victim accumulated and mixed with the wood ash of the fire. The resulting mass was washed off by rain into the clay soil of the banks of the Tiber River, where residents washed their 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

Slide Description:

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 with an admixture of beech ash. It came in three varieties: hard, soft and liquid. Soap was used not only for washing, but also for coloring the hair. They could not only wash, but also dye their hair yellow, pink or red. The Romans learned this from the Gauls, who wore long hair, and so that they lay well, they smeared them with vegetable oil, to which they added red earthy paint. When water got into this mixture, a thick foam was formed, thanks to which the hair became clean and fluffy. This is how one of the ways of producing Slide soap was discovered *

9 slide

Slide Description:

Soap was known to man before the new era of chronology. The earliest written mention of soap in European countries is found by 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, Cyprus, that is, in areas cultivating olive trees. The first German soap factories were founded in the 16th century Slide *

10 slide

Slide Description:

In 1779, the Swedish chemist Scheele showed that when olive oil interacts with lead oxide and water, a water-soluble sweet substance is formed. A decisive step towards studying the chemical nature of fats was taken by the French chemist Chevreul. their saponification with water and alkalis. Scheele's sweet substance 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 or potash). Soap can be toilet (for cleansing and caring for the skin) and technical (household) soap. Soap can be solid or liquid. The soap contains fats, oils, dyes, perfume compositions and other additives. The more natural ingredients in the soap, the better.If the soap contains synthetic additives, it belongs to the lower quality group Slide *

12 slide

Slide Description:

Types of soaps and their effectiveness -Children's hygienic soap -Hygienic antibacterial soap -Exfoliating soap -Perfume soap -Cosmetic soap -Liquid soap -Iodized soap Slide *

13 slide

Slide Description:

Natural components that make up the structure of the soap: - Essential oils - Plant extracts - Clay - Healing mud Slide *

14 slide

Slide Description:

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

15 slide

Slide Description:

We conducted a survey among the students of our school. 52 students participated in the questionnaire, and we got the following results: The following questions were included in the questionnaire: Slide * Question number Question Yes No 1. Soap production is chemical process? 44 8 2. Does soap play a significant role in maintaining human health? 51 1 3. Is it true that antibacterial soaps are considered more hygienic than liquid soap? 29 23 4. Is baby soap suitable for adults? 37 15 5. Is it possible to make soap at home? 32 20 6. Can I wash my 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 baby soap, in solid state

16 slide

Slide Description:

Do-it-yourself soap production methods. 1. Cold working 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 working method - Similar to cold working, but heat is required to speed up the soap making process. The advantage of the hot working 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. The regrouping method is a method in which molten soap bars are used as the basis for the production of soap. 4. Melting and Casting Method - Similar to the regrouping method, this soap making method is the easiest way for beginners to learn how to make soap with their own hands without mixing lye. The advantage is that you take the semi-finished natural soap base and add color, smell, and even texture to make your own soap. Knowing how to do natural soap self made, you can always present wonderful gifts to your loved ones. Slide *

17 slide

Slide Description:

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

To use the preview of presentations, create yourself a Google account (account) and log into it: https://accounts.google.com

Slide captions:

MADOU "CRR- Kindergarten No. 4 "Group No. 16" Luchiki " Research: "Soap and soap making" Completed by: Kamalieva Ralina Supervisor: S. Amigullina G.R.

It all started when my mother bought liquid soap at the store. It interested me. I thought, why liquid, and not ordinary, solid? I decided to find out as much as possible about soap. Purpose of work: To study the history of the origin and the process of making 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 how to make soap with your own hands. Find out which soap is better to trust: liquid or solid? Hypothesis: Liquid soap is more credible. Practical value: Liquid soap is more convenient to use. Research techniques and methods: Observations, study of literature, conversations, Internet resources. Research subject: soap.

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

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

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

And I wanted to know more about soap. How it is brewed, what people used before the invention of soap, and what is its composition. Now I will try to tell you about it. The history of soap is about 6 thousand years old. Before the invention of soap, grease and dirt were removed with ash and fine river sand. Also, various plants were used to wash hands and body, 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, about its composition and properties. So he wrote that soap is obtained 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 clothes. For centuries, people have refined the process of making soap.

Soap is the cleaning product we use every day. It happens different forms and sizes, various 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.

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

Add some soap and mix. As we can see, the soap "ate" the oil droplets. The fact is that soap molecules pounced on the fat droplets, surrounding them and dissolved in water.

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

1. From a soap base (special composition for the production of soap). 2. Soap "from scratch" from fats, oils and alkalis (such a soap is made at the factory). 3. "Soap from soap" - which I tried to make myself at home: I took baby soap. How to get soap at home?

I rubbed the soap on a grater. Melted in a water bath.

Arranged into forms. And here's what I did.

As we already know, soap can be solid or liquid. Which soap to 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 that it can be used in any situation. -it's cheap. Solid soap - its disadvantages: -it dries quickly. -it dries the skin. - leaves behind a raid. - microbes 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 hands - foam quickly. -has a persistent aroma -practical anti-allergenic. Disadvantages: - it is more expensive - it takes a lot of water to wash it off.

And what have we come to? Of course, in their composition, solid and liquid soaps differ little, but liquid soaps have more advantages. Therefore, our hypothesis that liquid soap is better was confirmed. While working on this study, I completed all the tasks. I learned a lot of interesting things and determined the meaning of soap in our life, showed the children in the group, you, how you can make soap at home. In the modern world, many varieties of soap are provided on the shelves of the store. We can choose the desired aroma, shape, composition. But hand-made soap is more pleasant to receive as a gift. Such 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, Republic of Bashkortostan

Research

on the topic of:

"Soap and soap making"

senior group №16

"Rayons"

Completed by: Kamalieva Ralina

Head: G.R Samigullina

It all started when my mother bought liquid soap at the store. It interested me. I thought, why liquid, and not ordinary, solid? I decided to find out as much as possible about soap.

Objective - to study the history of the origin and process of making soap, as well as find out which soap is better: liquid or solid?

Tasks:

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

Hypothesis: Liquid soap is more credible.

Practical significance:Liquid soap is easier to use.

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

Subject of study: soap.

Soap is an integral part of our hygiene. This is a product that people use when taking a bath or taking a shower to keep the body clean and smell pleasantly fresh. There is hardly a house without a single bar of soap!

There are many varieties 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 # 1

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

The history of soap is about 6 thousand years old. Before the invention of soap, grease and dirt were removed with ash and fine river sand. Also, various plants were used to wash hands and body, 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 # 2

In his notes, he left notes about soap, about its composition and properties. So he wrote that soap is obtained 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 clothes. For centuries, people have refined the process of making soap. In Russia, the production of soap 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 the cleaning product we use every day.

Appendix No. 3

Soap comes in a variety of shapes and sizes, with different flavors and dyes 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 a drop of sunflower oil. The oil will collect on the surface in a single layer. Now let’s blab it all out. The oil will break into small droplets. Now let's add some soap and mix. As we can see, the soap "ate" the oil droplets. The fact is that soap molecules pounced on the fat droplets, surrounding them and dissolved in water.

Appendix No. 4

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

How to get soap at home?

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

2. Soap "from scratch" from fats, oils and alkalis (such a soap is made at the factory).

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

Test 2

1. I took baby soap.
2. Grated.
3. Melted in a water bath.
4. I added some honey, oil and glycerin.
5. Stirred. The finished mass looks like sour cream.
6. I added a little dye to make it red.
7. Dropped a drop of fragrance.
8. Arranged into forms.

Appendix No. 5

And here's what I did.

Appendix No. 6

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

Which soap to trust more? Liquid or Solid?

We all know that we cannot do without soap. It turns out that the soap isn't all that harmless. Let's try to figure it out.

So,

Solid soap - its advantages:

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

It's cheap.

Bar soap - its disadvantages:

It dries quickly.

It dries out the skin.

Leaves a bloom behind.

Germs can 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.

Does not slip out of hands - it foams quickly.

Has a persistent scent

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

Appendix No. 8

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

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

Appendix No. 9

List of used literature

1. "DIY soap"
2. "Making soap at home"
3. "Stories about the substance"; edited by Heinrich Ehrlich. - M .: Yauza-press, 2011.-208 p.
4. "What is everything made of?" Strelnikova L.N.
5. ru.wikipedia.org ›Galen
6. ru.wikipedia.org ›Soap

Preview:

To use the preview, create yourself a Google account (account) and sign in to it:

Most types of dirt to one degree or another contain fat, and even if not, the same dust, settling on the skin, mixes with sebum, therefore, simply rinsing your hands with water, you cannot consider them clean. Fat does not dissolve in water. If you mix water with a small amount in a glass vegetable oil, you can see how the liquid separates into 2 components that do not want to have any connections with each other.

You can mix indefinitely, the maximum that can be achieved is an aqueous suspension of oil droplets, the so-called. The picture changes to the sharply opposite, if a little soap is dropped into the same glass. Three substances - water, oil and soap will combine into one, that is, soap will simply dissolve fat in water - finally and irrevocably.

How does soap work?

This dissolution process takes place as follows. Soap belongs to the category of so-called tensides and, like many other substances, consists of many tiny particles - molecules. The surfactant molecules have one remarkable feature. One side of the molecule is capable of attracting water, the other, on the contrary, repels it. Scientists call them hydrophiles and hydrophobes, respectively. Hydrophobes, in turn, are capable of attracting fat particles to themselves.

Thus, a kind of chain is obtained. A water molecule is attached to the tenside particle on one side, and a fat molecule on the other. That is, the fat dissolves, as it were, without leaving the slightest trace behind. All that remains is to wash off the resulting substance from a plate, hands or any other item that needed to be washed.

Soap production

Most of the soaps produced today are made from vegetable or animal fats by adding alkalis to them - potassium or sodium. A reaction occurs, the result of which is the decomposition of fats into glycerin and fatty acid salts. The consistency of the soap obtained depends on the length of the chains of the tensides formed. If stearic acid or palmitic acid salts are formed as a result of the reaction, the soap will be hard.

In this case, it also matters which alkali was used in the production. It is known that potassium salts in soap make it more plastic and hydroscopic, that is, liquid. But any soap, from household to cosmetic, uses the same principle of action on dirt - it dissolves it together with fat and is safely washed off, taking with it newly acquired "friends".



Soap has one very important quality, namely, it is able to significantly reduce the surface tension of water, and thereby significantly increase its detergent properties.

The soap foam consists of huge amount small bubbles, each of which has a water shell. It is these bubbles that are the main secret of the washing abilities of soap, they seem to absorb all the particles of dirt and dust that we have on our hands.

And then, under the influence of a stream of clean water, dirty soap suds are easily washed off from the surface of the hands and body. Soap can be used to clean industrial floors, as well as parquet in the house.

A deeper study of the question of why soap washes will require you to have a certain knowledge of chemistry, and more specifically, knowledge of the composition of the soap molecule. The peculiarity of soap is that upon contact with water, its molecules completely cover the entire water surface, forming a kind of palisade.

It is this property of soap that makes it possible to reduce the surface tension of water, and therefore to enhance its wetting ability. And this, in turn, helps to better wet the surface of hands, matter or any other contaminated object.

So what happens next?

Particles of dirt or dust are completely covered with soap molecules, and then are easily separated from the surface of the skin and matter, immersed in the mash solution, turning into an emulsion or suspension.

Soap molecules have a very strong enveloping property, which prevents dirt and dust from reattaching to the surface of hands and fabrics, which facilitates their speedy rinsing with a stream of clean water.

So, if we simply explain why soap washes at the same time, without plunging deeply into science, it is necessary to say the following that soap foam has an excellent property to easily absorb all particles of dirt, grease and dust located on a contaminated surface, after which it is no less easy wash off with plain clean water.

After such a procedure, the previously contaminated surface becomes absolutely clean and safe.

Today there are many types cosmetic soap, which has not only washing, but also caring properties. Various useful supplements included in the composition of cosmetic soap, you can endow it with a variety of properties, such as moisturizing, emollient or antibacterial. Each manufacturer gives their soap a different color, shape and scent.

And yet the most important quality of soap is its amazing ability to easily and simply remove a variety of contaminants from the surface of hands and fabric.