This article is a summary of the main work. Full text scientific work, applications, illustrations and other Additional materials available on the website of the II International competition of research and creative works of students "Start in Science" at the link: https://www.school-science.ru/2017/13/26922.
Water is the beauty of nature! We see this beauty everywhere: in a quiet river shrouded in fog, and in the depths of the lake, on which swans sail in white boats, and in the blue sea, where a fast ship cuts the waves. This beauty is also in the thin stream of water with which we wash ourselves. She is in the clouds running across the boundless ocean of air. And in the mushroom rain, which watered every bush with moisture. What if there was no water? It's scary to even think about it. There would be no rain, no snow, rivers, seas, lakes would dry up, grasses and trees would burn. This means that there would be no fish, birds, animals and humans. There would be no life on Earth.
Water is not just an ordinary liquid. It is the most common substance in nature and the main component of all living organisms. How much water is on earth? Many or few? Earth is sometimes referred to as the "Blue Planet". It turns out that water covers 70% of the Earth's surface. Scientists have calculated that 97% of all water reserves on planet Earth are in the salt waters of the seas and oceans, and only 3% of the water reserves are fresh water, which is very small.
In nature, it fills the bowls of the oceans, seas, lakes, rivers, swamps. There are also artificial reservoirs - ponds, reservoirs and canals. It is also in the depths of the Earth, and in its atmosphere. She constantly makes a cycle in nature. When the sun heats the Earth's surface, water turns into vapor and enters the atmosphere. When water in the atmosphere cools, it forms clouds. Then some of this water again falls to Earth in the form of rain. Among all the blessings given to us by nature, water occupies a special place. Water is a unique wealth of living nature. There is no such person who does not know what water looks like. Every day we wash our faces, brush our teeth, wash our hands, take a shower, but often we don’t think about how clean water gets into our house and where does it come from? What properties does it have? And can it happen that suddenly there is no water? What is clean, high-quality water like?
One day I asked myself this question. That is why I chose this topic.
Relevance of the topic: Water is the main component of life. It is necessary for the life of humans, plants and animals, therefore, it is necessary to study it.
The goal is to clarify and expand knowledge about water, its properties, and its significance for humans.
Analyze scientific information on the topic;
To study the role of water in human life;
Analyze the impact of water quality on human health, water ecology;
Learn how water is purified, what properties it has;
Conduct a survey;
Do experiments with water.
Object of study: water.
Subject of research: water quality and its properties.
I put forward the hypothesis of the study that a person treats water unreasonably and needs it. Everyone should save water!
During my work, I used the following research methods:
Observation;
Collection of information from books, magazines, newspapers;
Questioning;
Experiences, comparison;
Generalization.
experimental part
Hypothesis. Water has no taste, smell, color, shape, and is fluid.
a) define properties liquid water, pour water into one glass, milk into another, cherry compote into the third. Let's compare with the help of the senses water, compote and milk, determine the color, taste and smell of water. Let's drop one spoon into a glass of water, another - into a glass of milk, the third - with compote). Water is colorless, tasteless, odorless. Water has no form. It takes the form of the vessel it fills. Drop water on any surface. Let's look at its shape. Let's add three or four more drops. A large drop of water spread out. This property of water is called fluidity. All liquids have it.
Conclusion: water has no smell, taste, shape, it is transparent and fluid.
Hypothesis. Substances dissolve in water.
b) Pour water into a glass, add a spoonful of granulated sugar and stir. The water will become sweet. Pour a spoonful of salt into another glass and stir. The water will become salty. Other substances also dissolve in water. Minerals can be absorbed by plant roots only by dissolving in water.
Conclusion: water is a good solvent.
Experiment #2
Hypothesis. Water retains heat.
We have pipes throughout the house for heating, and in these pipes there is water. Pipes heat our house and retain heat for a long time.
Conclusion: the ability of water to retain heat for a long time is a property of heat capacity.
Experiment #3
Hypothesis. Water is the only substance on Earth that exists in three different states at once: liquid, gaseous and solid.
1. Pour water into the kettle and bring to a boil. Boiling water turns into transparent water vapor, which we cannot see. This process of transition of liquid water into gaseous state called evaporation. Cooling in air, the vapor turns into fog. Fog is tiny droplets of liquid water. This is what we see when it bursts upward from the spout of the kettle with a jet.
2. Put a cold spoon to the teapot spout. It is instantly covered with the smallest droplets of water. We take out a spoon with drops in the cold or put it in the freezer - the spoon will be covered with an ice crust. We bring it into warm room- there will be water in the spoon again. We returned the water to its original state.
Conclusion: water has three states of aggregation - solid, liquid and gaseous.
Experiment #4
Hypothesis. One of the properties of water completely contradicts all the laws of nature and at the same time is one of its most important laws. We know that when heated, all substances expand, when cooled, they contract, and when they freeze, the volume of water increases.
If you pour water into the bottle up to the neck, close it tightly and put it in the cold. The bottle will burst. So, when the water freezes, it became not less, but more!
Note: Water expands when heated and contracts when cooled.
Experiment No. 5. "The structure of water and how to prepare structured water at home?".
Hypothesis. To date, there are several ways to prepare structured water at home.
There are two ways to get healthy structured water at home.
1. We take clean filtered water, pour it into an enamel pan and put it in the freezer of the refrigerator. The first ice that appeared, such an ice edge, is the same heavy water with deuterium that freezes at + 3.8 ° C. We don’t need it, we get rid of it, leave it in a saucepan, and pour the rest of the water into another bowl and put it back in the freezer.
Water begins to freeze again, and when it freezes somewhere by 2/3, in the middle there will be water with ultralight isomers (they freeze last at below -1 ° C), which will contain all the dirty chemical impurities. We also get rid of this water, and the ice that we received as a result is the purest and most useful water, alive and ideally structured for our body.
Conclusion: structured water acts in a complex way, contributing to the healing and rejuvenation of the body, stimulating the metabolism, and releasing energy for a quality life. This structured water therapy gives quick results. Remember that fresh fruits, vegetables, greens contain structured water. Make the most of summer time to nourish your body cells, cleanse and renew your water structure!
But what are microspheres? I will probably study and write about how medical products with Alsariya microspheres are made in my next project, because. You also need to know chemistry.
Experiment No. 6. Sociological survey.
In order to find out the level of knowledge of schoolchildren about the quality of drinking water and its effect on the human body, I conducted a survey among schoolchildren.
The result of the survey showed that more than half of the respondents do not consume raw water. When asked what kind of water you drink more often, 30 people out of 50 said boiled, 10 people filtered, and 10 people raw.
During a survey on water quality, it turned out that more than 60 people out of 100 believe that it is necessary to improve the purification system, 38 people believe that water should be tested more often for suitability for use. The reason is that the population is not sufficiently informed about the consequences of the impact of low-quality water on the body of each of us. Adults and schoolchildren underestimate the harm caused by such drinking water all living beings and the human body.
Based on the results of the survey, it was concluded that this problem is relevant and important for each of us. Many people have superficial, fragmentary knowledge about the problem of the impact of water on living organisms, including the human body. Not every one of the respondents connects the existing diseases, various ailments with the quality of drinking water. Draw conclusions about the importance of water.
Conclusion
Today, the water problem has become one of the most important. Thanks to water, life originated on our planet and still exists. We are accustomed to water and often forget that water is the greatest treasure on Earth. But water resources are not unlimited. If water disappears, life will also disappear. Our planet will become the same lifeless planet as other planets in the solar system.
Water is part of every cell! Forests and fields drink water. Without it, neither animals, nor birds, nor people can live.
Everyone needs clean water. She is the basis healthy life. But clean water is becoming less and less. And the people themselves are to blame. Wastewater from factories and plants, as well as water used in everyday life, merge into rivers and lakes. All living things suffer from water pollution.
Let's save water, the same simple water that flows from a water tap, splashes in rivers and lakes, the one that we drink from a spring, because saving water means saving life!
Saving water is not greed. This is frugality, care for the generations of people who will live after us.
Water is a wonderful object of inanimate nature! Water is unique!
Bibliographic link
Nizamov E.Z. AMAZING PROPERTIES OF WATER // Start in science. - 2016. - No. 6. - P. 100-102;URL: http://science-start.ru/ru/article/view?id=511 (date of access: 09/02/2019).
Fundamentals of modern understanding physical and chemical properties waters were laid about 200 years ago by Henry Cavendish and Antoine Lavoisier, who discovered that water- it's not simple chemical element, as medieval alchemists believed, and the combination of oxygen and hydrogen in a certain ratio. (see fig. 3)
Actually, its name is hydrogen ( hydrogene) - giving birth to water - received only after this discovery, and water acquired a modern chemical designation, now known to every schoolchild, is H2O.
2.1. Water standard for measuring temperature, mass, amount of heat and height
Swedish physicist Anders Celsius, (see Fig. 4) a member of the Stockholm Academy of Sciences, created in 1742 the centigrade thermometer scale, which is now used almost everywhere. The boiling point of water is 100° and the melting point of ice is 0°. (see fig. 5)
When developing metric system, established by decree of the French revolutionary government in 1793 to replace various ancient measures, water was used to create the main measure of mass (weight) - kilogram and gram: 1 gram, as you know, is the weight of 1 cubic centimeter(milliliter) of pure water at the temperature of its highest density + 40C. Therefore, 1 kilogram is the weight of 1 liter (1000 cubic centimeters) or 1 cubic decimeter of water: and 1 ton (1000 kilograms) is the weight of 1 cubic meter of water. (see fig. 6)
Water is also used to measure the amount of heat. One calorie is the amount of heat needed to heat 1 gram of water from 14.5° to 15.50 C. (See Fig. 7)
All heights and depths on the globe are measured from sea level. (see fig. 8)
2.2 Three states of water
Despite the centuries-old history of study, the simplest chemical composition and exceptional importance for life on Earth, the nature of water is fraught with many mysteries. Only water we can see at once in its three states. (see Fig. 9) When severe frosts hit, you can observe how steam rises above the surface of the water of a lake or river, and a crust of ice has already formed near the shore.A very rare property of water is manifested during its transformation from a liquid to a solid state. This transition is associated with an increase in volume and, consequently, with a decrease in density. As water solidifies, it becomes less dense - so ice floats instead of sinking. The ice thereby protects the underlying layers of water from further cooling and freezing.
In addition, it was found that water has the highest density at a temperature of +4°C. When the water in the reservoir cools, the heavier upper layers sink, resulting in good mixing of the warm, lighter deep water with the surface water.
Therefore, reservoirs do not freeze to the bottom and life in the water continues. Unique properties waters appear when heated. Its heat of vaporization is extremely high. For example, to evaporate 1 gram of water heated to 100°C, it takes 6 times more heat than to heat the same amount of water from 0 to 80°C.
2.3 "Supercooled" water
Everyone knows that water always turns to ice when it cools down to zero degrees Celsius... except when it doesn't! " Supercooling' is the tendency of water to remain liquid even when cooled to temperatures below freezing.
This phenomenon is made possible by the fact that Environment does not contain centers or nuclei of crystallization, which could provoke the formation of ice crystals. That is why water remains in liquid form, even when cooled to temperatures below zero degrees Celsius.
When the crystallization process starts, one can observe how " supercooled» water turns to ice in an instant. But under any circumstances, at -38°C, the most supercooled water will suddenly turn into ice.
What happens when the temperature drops further? At -120°C, ice becomes viscous like molasses, and at -135°C and below, it turns into " glass" or " vitreous» Water is a solid with no crystals.
2.4" Mpemba effect»
In 1963, high school student Erasto B. Mpemba (see Figure 10) noted that hot water Freezes faster in the freezer than cold. The physics teacher, with whom the young man shared his discovery, made him laugh.
Fortunately, the student was persistent and convinced the teacher to conduct an experiment, which proved him right. Now the phenomenon of hot water freezing faster than cold water is called " Mpemba effect". Scientists do not fully understand the nature of this phenomenon.
2.5 Change in properties of ice under pressure
Another interesting water property: an increase in pressure causes the ice to melt. This can be observed in practice, for example, the sliding of skates on ice. The area of the ridge blade is small, so the pressure per unit area is large and the ice under the ridge melts.
It is interesting that if you create over water high pressure and then it is cooled to freezing, then the ice formed under conditions of increased pressure does not melt at 0 ° C, but at a higher temperature. So, ice, obtained by freezing water, which is under a pressure of 20,000 atm., Under normal conditions, melts only at 80 ° C.
In addition, water practically does not compress, which determines the volume and elasticity of cells and tissues. So, it is the hydrostatic skeleton that maintains the shape of roundworms and jellyfish.
2.6 Heat capacity of water
The specific heat capacity is understood as the amount of heat that can heat 1 g of the mass of a substance by 1 °. This amount of heat is measured in calories. Water perceives at 14-15 ° more heat than other substances; for example, the amount of heat required to heat 1 kg of water by 1° can heat 8 kg of iron or 33 kg of mercury by 1°.
Water has a huge heat capacity and it is no coincidence that it is used as a coolant in heating systems. For the same reason, water is also used as an excellent coolant.
The high heat capacity of water protects the tissues of organisms from a rapid and strong increase in temperature. Many organisms cool themselves by evaporating water.
2.7 Thermal conductivity of water
Thermal conductivity is understood as the ability of various bodies to conduct heat in all directions from the point of application of a heated object. Water has a very high thermal conductivity and this ensures a uniform distribution of heat throughout the human body and warm-blooded animals.
2.8 Surface tension of water
One of the very important properties water is the surface tension. It determines the strength of adhesion between water molecules, as well as geometric shape its surface. For example, due to surface tension forces, a drop, a puddle, a jet, etc. are formed in different cases.
There are whole species of insects that move along the surface of the water precisely due to surface tension. The most famous are water striders, which rely on the water with the tips of their paws. The foot itself is covered with a water-repellent coating. The surface layer of water bends under the pressure of the foot, but due to the force of surface tension, the water strider remains on the surface.
We are so accustomed to the effects caused by surface tension that we do not notice them unless we have fun blowing soap bubbles. However, they play a significant role in nature and our life.
The unusually high surface tension of water has led to its good ability to wet surfaces. solids and show capillary properties, which gives it the ability to rise up the pores and cracks of rocks and materials in spite of gravity. It is this property of water that ensures the movement of nutrient solutions from the root to the stem, leaves, flowers and fruits of plants.
2.9 Water is the universal solvent
We look at a mountain spring and think: “ This is truly pure water!» However, this is not so: there is no ideally pure water in nature. The fact is that water is almost a universal solvent.
It contains nitrogen, oxygen, argon, carbon dioxide- and other impurities in the air. The properties of the solvent are especially pronounced in sea water. It is generally accepted that almost all elements of the table can be dissolved in the waters of the World Ocean. periodic system elements, including rare and radioactive.
Most of all, it contains sodium, chlorine, sulfur, magnesium, potassium, calcium, carbon, bromine, boron and strontium. Only 3 kg of gold is dissolved in the World Ocean for each inhabitant of the Earth!
There are hydrophobic (from the Greek hydros - wet and phobos - fear) substances that are poorly soluble in water, such as rubber, fats, and the like. And also, hydrophilic (from the Greek philia - friendship, inclination) substances, those that dissolve well in water, such as alkalis, salts and acids.
The presence of fat does not allow the human body to dissolve in water, since the cells of the body have special membranes containing certain fatty components, thanks to which water not only does not dissolve our body, but also contributes to its vital activity.
Many modern scientists and thinkers have long come to the conclusion that the space around us is a single living organism, with its own properties and laws, which are still far from being fully revealed to mankind. Great amount scientific discoveries made only in the last century, more and more convinces us of this.
Today, environmentalists around the world are sounding the alarm: our civilization is in danger. Natural resources are mercilessly depleted, the natural habitats of all living things are changing before our eyes, the number of threats to the existence of life on Earth is steadily increasing. After all, even such simple thing Just as ordinary drinking water may well become more expensive than oil in the foreseeable future, the terms "water purification" and "water treatment" are already well-known not only among specialists.
For so many years we thoughtlessly squandered our water resources, poured industrial waste into reservoirs and Agriculture, poisoned everything around with domestic sewage, that ordinary clean water is now sold in bottles, and that which flows through city water pipes needs to be filtered.
Preliminary water treatment today is an integral stage of all industries whose products are manufactured using ordinary water. Entire scientific organizations are working on the creation of new, more advanced water treatment and purification systems. Wastewater.
Meanwhile, in nature there is no more mysterious substance than water. And while some experts are improving water purification methods, others are discovering more and more new features of this liquid, so widespread on the planet, which exists contrary to many laws of physics.
Even schoolchildren know that when cooled below +4 °C, water does not shrink, but expands. All bodies in the solid state are heavier than in the liquid state, and water is lighter. Gases, mixing with each other, do not form liquids, but oxygen and hydrogen give us water.
Regardless of passing through water treatment systems, any volume of water is one giant molecule. Water remembers everything that happened and spreads information not only throughout the cell, but throughout the body. Water even has its own energy and "genetic memory". Just imagine, like any other impact, water remembers both water purification and water treatment.
Very interesting experiments with water, which are engaged in the Japanese researcher Masaru Emoto. The scientist did not look for new methods of water treatment, he experimentally proved that if two samples of water are frozen, the crystals will always differ from each other, and their shape reflects information about the effects that were exerted on it.
In the process of research, Emoto studied water samples from sources around the world. AT laboratory conditions the water was exposed to electromagnetic radiation from a TV and a mobile phone, the sounds of music and various images. Groups of people directed their thoughts and prayers to the water, the water was exposed to oral speech in different languages. All changes occurring in the structure of water were recorded on film.
When processing the results of the experiments, it was found that water reacts to the thoughts and emotions of others. Crystals of the usual hexagonal shape were obtained from distilled water. Then it was noticeable how they change their structure in the process of accumulation of positive information and collapse under the influence of negative information.
It turns out that water, as a highly qualified cryptographer, encodes the information it receives. And we still can't decipher it. It is known for certain that information is perceived and reflected by water in the form of a geometric structure of crystals, which are its images.
Wolfgang Ludwig proved that even after complete purification of water from heavy metals, nitrates, bacteria by double distillation, information about these substances is stored in the form electromagnetic oscillations. That is, water treatment frees water from harmful impurities, and information about their past existence can still be read.
The purpose of the lesson: discover the amazing properties of water.
Lesson objectives:
1. Based on the structure of water molecules, get acquainted with its properties.
2. Explore the properties of water, prove its uniqueness.
3. Form the concept of water as a priceless gift.
Lesson plan.
- Introduction by the teacher. The world is not made by hands.
- Viewing a fragment of the film "The Great Mystery of Water".
- The structure of water molecules and its properties.
- Group work.
- Presentation of musical impressions of water.
- Another mystery is baptismal water.
- Ecology of water.
- Findings. Why should water be conserved?
- Homework.
Introduction.
So, we watched a clip from the movie. What properties of water seemed surprising to you, what did you write down in your notebooks?
Suggested student responses:
- The molecule is small.
- Three aggregate states: solid, liquid and gaseous.
- The density of ice is less than that of water (it expands at sub-zero temperatures).
- High surface tension;
- Water is a powerful solvent;
- Creates huge pressure (rises up through the vessels of plants).
Teacher: Well done guys, you are very attentive! Now let's take a closer look at listed properties. Now you have to work in groups. Each group will receive task cards. Check out their content. Answer the questions or write down the missing words. The time allotted for work with cards is 3 minutes. The guys are divided into 6 groups and, according to the proposed questions, they make up a plan for the answer. The conclusion in each group is the definition of one of the amazing properties of water. Group cards: (See Appendix 2.)
At the end of the lesson in notebooks, there should be an entry:
Water is a small molecule that has very specific properties:
- Water under normal conditions is a liquid, because. its molecules are polar and connected by hydrogen bonds, i.e. form large associations.
- The density in ice crystals decreases at 4°C, so the ice floats on the surface (life continues under the ice).
- Water is a powerful solvent, thermostat.
- Water has a high surface tension.
- Water has mobility (freezing, evaporation and melting); water circulates (water cycle in nature). Water takes the form of a vessel.
- Water can rise up through the vessels of plants, creating a large Atmosphere pressure transporting minerals.
Completing tasks in cards, students must draw conclusions and name one of the amazing properties of water (each group). The teacher corrects the answers and talks about those concepts that will complement the answers of the children, introducing them to new concepts for them.
Teacher: What is the composition of a water molecule?
Student: A water molecule consists of one oxygen atom and two hydrogen atoms.
Teacher: What type of chemical bond is there between atoms in a water molecule?
Student: Between atoms O-N connection covalent polar.
Teacher: What is the molar mass of water?
Student: The molar mass of water is 18 g/mol.
Teacher: The molar mass of air is 29 g/mol, which is more than 1.5 times the mass of water, so why isn't water a gas? Let's figure it out.
Teacher: The water molecule looks like an isosceles triangle, the vertices of which carry partial charges O δ- and H δ+.
The structure of the water molecule.
Like a magnet, it has two poles - positive and negative. Therefore, the water molecule is depicted as a dipole.
Dipoles can be attracted to each other and form associates (associations), which become thousands of times more in mass than the mass of one water molecule. Therefore, water is not a gas, but a liquid. Water molecules are connected to each other through hydrogen bonds. A hydrogen bond is a chemical bond that connects different molecules. It occurs between the hydrogen atom of one water molecule and the oxygen atom of another water molecule. Such a bond is much weaker than all other types of chemical bonds.
Water can be in three states of aggregation - liquid, solid and gaseous.
Boiling point of water is 100°C, melting point is 0°C. These are also abnormally high values. Scientists explain this fact by the fact that water molecules are able to combine into aggregates using hydrogen bonds. On the gap, which, and is spent a large number of thermal energy when heated.
When heated, the distance between water molecules increases, hydrogen bonds between them are destroyed and therefore the water turns into gas, or water vapor.
1. When cooling, the distance between molecules decreases, at t = 0 ° C, water turns into solid crystals. One of the amazing properties of water is that at t = 4 ° C, the density in ice crystals decreases and due to this property, water in lakes does not freeze to the bottom, preserving life under the ice.
2. Thanks to the same ability (lower ice density than cold water), the resulting icebergs float on the surface.
3. Water is a powerful solvent. Absolutely pure water does not exist in nature. Absolutely pure water is distilled water, it is also called dead water. Various salts are always dissolved in natural water. Penetrating into all layers of the Earth, water dissolves the minerals that are in it. Water can dissolve and solids both liquid and gaseous. Water also plays a huge role in various life processes of a living organism, because. exactly at aqueous solutions there is an interaction between substances. Water accelerates many processes in the body, and is also a powerful thermoregulator.
In a planetary sense, water also plays a huge role. Its heat capacity does not allow our planet to cool down or overheat much, because. Water cools very slowly and heats up very slowly. Thanks to this ability of water, the climate on our planet is regulated.
4. Another amazing property of water is its high surface tension. Surface tension is one of the important parameters of water. It determines the strength of adhesion between water molecules, as well as the shape of the surface of the liquid. For example, a drop is formed due to surface tension forces.
The surface tension of pure water is greater than that of any other liquid. Absolutely pure water has such a surface tension that one could skate on it. Due to the presence of impurities, the surface tension of water decreases sharply.
5. One of the main properties of water is its mobility, due to the rapid change of form, which entails constant freezing, evaporation and melting.
It should be noted that water is underground, ground and air. These forms of water do not exist separately from each other. Water constantly circulates between these three points. This circulation is called the water cycle in nature.
An amazing property of water is that water is able to rise up through the vessels of plants, carrying with it mineral (inorganic) substances dissolved in it. Water is capable of creating enormous pressure of several hundred atmospheres, thanks to this property, a gentle sprout easily breaks through asphalt.
Water is an unusual substance. There is no substance on Earth more important for us than ordinary water, and at the same time there is no other substance of the same kind, in the properties of which there would be as many contradictions and anomalies as in its properties.
There is another amazing property of water. S. will tell you about this amazing property (advance task).
Two more properties of water appear in notebooks - these are:
- Water has memory.
- Amazing riddle- Epiphany water.
On the board, the teacher fixes cards with the conclusions that the students make on magnets. (Appendix 4.)
Teacher: Can we say that water is a priceless gift?
Student: Yes, because...
Teacher: A person can be a creator when he builds beautiful buildings, architectural structures. It can turn river beds, launch a rocket into space, and so on. But to create the sky, the sea, mountains, water is not subject to him, the human mind has not reached such a level. Water also has a CREATOR. For an Orthodox person, the Creator is God.
“Consciousness precedes the embodiment of ideas. God is a great architect." D.S. Likhachev (1906–1999), historian, culturologist.
Teacher: Guys, another message about the ecology of water was prepared for you by M. Let's see her presentation. (Presentation 4. Ecology of water.)
Teacher: There is a lot of water on our planet. But in everyday life we use only fresh water. Is there a lot of fresh water on the planet?
Almost 70% of the surface of our planet is occupied by oceans and seas. Of the total amount of water on Earth, equal to 1 billion 386 million cubic kilometers, 1 billion 338 million cubic kilometers falls on the share of salty waters of the World Ocean, and only 35 million cubic kilometers falls on the share of fresh waters. For each inhabitant of the Earth, there are approximately 0.33 cubic kilometers of sea water and 0.008 cubic kilometers of fresh water. But the difficulty is that the vast majority of fresh water on Earth is in a state that makes it difficult for humans to access. Almost 70% of fresh water is contained in the ice sheets of the polar countries and in mountain glaciers, 30% is in aquifers underground, and only 0.006% of fresh water is simultaneously contained in the channels of all rivers.
Teacher: So much or little water on Earth?
Student: Not much! Most of the water is salty, and every day a person needs more and more fresh water. Humanity is threatened by a crisis due to water pollution. Some countries are already experiencing a shortage of clean fresh water and are forced to import it from abroad. Water must be saved!
Let's summarize the lesson. Why is water unique? Why save water?
Homework.
Prepare a message about how water is purified before it enters our tap. Draw a diagram of a water treatment plant.
MUNICIPAL BUDGET GENERAL EDUCATIONAL
INSTITUTION SCHOOL №19 OF THE CITY DISTRICT OF KINESHMA
NAMED AFTER 212 TOMASHOVSKY KINESHEMSKY
RIFLE REGIMENT OF THE 49TH IVANOVO DIVISION
(MBOU school No. 19 named after the 212th regiment)
Scientific - research project
"The Amazing Properties of Water"
I've done the work:
student 4 "G" class
Semyonov Stepan
Supervisor:
Tsvetkova
Svetlana Vladimirovna
teacher primary school
Kineshma 2017
Content.
1. Introduction.
2. Goals and objectives.
3. Relevance.
4.History.
5. Composition.
6. Questioning.
7.Practical part.
8 .Conclusion and conclusions.
9 .References.
1. Introduction.
Water! You have no taste, no color, no smell.
You cannot be described, you are enjoyed
without knowing what you are! You can't say that you
necessary for life: you are life itself. You
You fill us with a joy you can't explain
our feelings ... You are the greatest wealth
in the world…
Antoine de Saint-Exupery
Water is a liquid composition that is odorless, tasteless and colorless. This is a secret of secrets. A person should look deeper into its essence. Water is the main miracle of the planet, it is the source from which life feeds!
Water occupies a special position among the natural resources of the Earth, it is irreplaceable, it has been necessary in all ages and wherever terrestrial life forms exist.
2. Topic of research work:
"The Amazing Properties of Water"
I decided to start my research work, puttinggoal : to find out what properties water has in different states and when interacting with various substances.
I then formulatedtasks :
Find information about what properties water can have;
Ask classmates if they know about the properties of water;
Get answers from the chemistry teacher to my questions;
Conduct experiments.
Object of study : water.
Subject of study : what are the properties of water.
Research methods:
Experiments, photo and video recording;
Work with informative sources;
Social survey, conversation;
Analysis and generalization of information.
3. Relevance : Watercovers about 2/3 of the surface of our planet. A person consists of about 65% water. A person needs living water just like most animals. Plants also need water in the soil. Life, as we understand it, is impossible without water. At least that's why it can be considered magical.
Hypothesis : water in various states and in interaction with other substances has amazing properties.
4.History.
Water is everywhere; she touches the past
and prepares the future; it flows under the poles and
present at high altitudes. If there
something truly mysterious on this planet,
so it's water.
Lauren Eisley
The origin of the word "water" is not exactly known. It arose in ancient times, and since then, they have been talking about any “living” liquid, without which our existence is impossible, as well as all of nature. The origin of the word "water" has another explanation. Water is very similar to the word "Veda" - Yes, which means - good truth. Thus, the name of the water is encrypted. And this property is given to her precisely in the Russian language.
Since ancient times, the highest minds of mankind have been asking themselves the question: what is the essence of water, what is its significance in human life? First scientific discovery in this area, which has come down to us, is called "The Teaching of the Four Elements." It was written inIVcentury BC e. ancient Greek philosopher Aristotle. The four elements are earth, fire, water and air. Moreover, water serves as a source of cold and moisture. In subsequent times, water still attracted the attention of the best scientists of its time. BeforeXVIIIcentury AD e. this substance was considered a separate chemical element.
Information about the presence of water chemical compound became known only in the 19th century. It was only through experiments that it was proved that water is a chemical compound, and not a chemical element. Thus, through long-term research, the classical formula of water was obtained.
5. Composition.
Water is a special liquid. The water molecule consists of 2 hydrogen atoms and one oxygen atom. Thus, her chemical formula – H2O .
AT Everyday life we can meet water in any of its three states, and its form is constantly changing. liquid waterevaporates
that is, it changes from liquid to gaseous state. The gaseous form of water iswater vapor.
water vaporcondenses
or changes from vapor to liquid. If you heat water to 100 degrees, it boils and turns into hot water vapor. At 0 degrees, water freezes and turns into solid ice.
6. Questioning:
In my class, I conducted a small questionnaire.
Target: ask your classmates if they know that water has amazing properties and if they want to learn about them.
Questions:
1. Have you ever experimented with water at home?
2. Do you think that if you put a paper clip in a glass of water, it will sink?
3. What do you think is heavier water or oil?
a) oil;
b) water;
c) are the same.
4. Would you like to test this on the example of my experiments with water and see clearly?
As a result of the survey:
1. Experiments with water were carried out at home by 10 people, which is 44%;
2. 9 people, 39%, thought that a paper clip would sink in a glass of water;
3. To the question: what is the hardest thing, 10 people, 44%, answered that oil;
9-39% of people thought that water and 4 people, 17%, wrote that they are the same.
4. 22 out of 23 respondents, 96%, would like to see all the experiments visually.
Conclusion : my classmates became interested and would like to see these experiments visually.
7.Practical part.
Experiments 1, 2,3,4.
Target : Prove that water has a large surface tension.
Experience 1.
Would need:
Water;
Coin;
Pipette.
Instruction:
one). I took the coin and laid it on a flat surface.
2). He carefully began to drip water from a pipette onto the coin.
3). 45 drops of water were removed on a two-ruble coin. At the same time, the water did not drain from the coin and took on a convex shape.
Conclusion: water has a high surface tension. And it is precisely because of him that drops of water do not drain from the coin, but firmly hold the convex shape.
Video attached.
Experience 2.
Would need:
Water;
Cup;
Metal clip.
Instruction:
one). I poured water into a glass.
2). Then he tried to put a paper clip on the water. First the paperclip sank.
3). Then I tried to make everything neat. Experience turned out! The paperclip floated on the surface of the water
Conclusion: water has a high surface tension. It keeps the small metal clip from sinking.
Video attached .
Experience 3.
Would need:
Water;
Plate;
Ground pepper;
Liquid soap.
Instruction:
one). I poured water on a plate.
2). Sprinkled ground pepper. It spread over the surface of the water.
3). I put some liquid soap on my finger and dipped my finger into the center of the plate. All the peppers are drawn to the edges of the plate.
Conclusion: water has a high surface tension. The soap, on the other hand, loosened the surface tension of the water in the center of the plate, and so the pepper was attracted to the edges of the plate, where the surface tension remained high.
Video attached .
Experience 4.
Would need:
soap solution;
Straw.
Instruction:
1). We have prepared a soap solution in advance.
2). I went to blow bubbles on the street. The air temperature was below -15 degrees. I wanted to see what would happen to soap bubbles in the cold.
3). I gently blew bubbles onto the snowy surface. They did not burst, but froze, and eventually broke like a film. This was very beautiful.
Conclusion: water has a high surface tension. The soap reduced the surface tension and allowed the surface of the water to stretch and create soap bubbles. .
Video attached .
Conclusion: After a few experiments, I came to the conclusionthat water has a high surface tension.
Experiments 5.6.
Target: Prove that water pressure is less than air pressure.
Experience 5.
Would need:
Water;
Empty bottle;
Plastic ball.
Instruction:
1). I poured a full bottle of water.
2). Put a plastic ball on the neck and turned the bottle over. He didn't fall.
Conclusion: on the one hand, water presses on the ball, and on the other hand (from the very bottom) - air! The water pressure in the bottle is less than the air pressure, so the ball does not fall.
Video attached .
Experience 6.
Would need:
Water;
Dye;
Plate, glass;
Coin;
Chewing gum;
Matches.
Instruction:
1). I poured water, tinted with dye, onto a plate.
2). I put chewing gum on a coin and attached three matches to it.
3). I put this design in a plate with water and set fire to the matches.
4). Quickly covered the burning matches with a glass. When the matches went out, the water was drawn into the glass.
Conclusion: the fire heated the air inside the glass. As a result, the air expanded, which means that its pressure also increased. As a result, part of the air from the glass began to come out. When the fire went out, the air cooled down and again decreased in volume, which means that its pressure also decreased and became less than the pressure of the outside air. It was this external pressure that pressed the water into the glass.
Video attached .
Conclusion: water pressure is less than air pressure.
Experience 7.8.
Target: Prove that passing through water, light can change its direction.
Experience 7.
Would need:
Water;
Empty jar;
Several coins.
Instruction:
one). I poured water into a jar. I put two coins under the jar. Then he looked through the water on the side of the jar and did not see a coin.
3). To add more interest to the experience, I dropped a coin into the jar. You could see it through the glass. Looking down, I saw all three coins.
Conclusion: When light passes from a less dense medium - air, into denser water, at the border of these two substances, the direction of the light rays changes. Passing from water to air. When light passes from the denser medium of water to the less dense medium of air, the light is deflected in the opposite direction. Therefore, we do not see the coin.
Video attached .
Experience 8.
Would need:
Water;
A sheet of paper with drawn arrows;
Empty jar.
Instruction:
one). I placed the sheet with the drawn arrows behind the empty jar.
2). Then I began to pour water into the jar. As the water reached the arrows, they changed their direction.
Conclusion: a can of water works like a lens. When a beam of light passes through a lens, it bends towards the center. The point where the rays come together is called the focus, but beyond that point the image flips because the rays change direction.
Video attached.
Conclusion: A ray of light passing through water can change its direction.
Experience 9.
Target: prove that the density of cold water is greater than the density of hot water.
Would need:
Two glasses with cold water;
Two glasses with hot water;
Dyes;
Plastic card.
Instruction:
one). I added yellow dye to glasses of cold water, and red to glasses of hot water.
2). I put a plastic card on a glass of cold water. I turned the glass upside down, placed it on top of a glass of hot water, and carefully removed the card. Cold and hot water mixed.
3). Then, in the same way, we put the glass of hot water on top of the glass of cold water. Cold and hot water did not mix.
Conclusion: The density of cold water is greater than the density of hot water.
Video attached.
Experience 10 "Lava lamp":
Target: prove that water is heavier than sunflower oil.
Would need:
Water;
Sunflower oil;
Dye;
Aspirin effervescent tablet;
Jar.
Instruction:
one). I filled 1/3 of the jar with water and topped up the rest with oil.
3). Dropped an effervescent aspirin into the jar.
4). Water is heavier than oil. In addition, they have the property of not mixing. When I added effervescent tablets inside the jar, they, when dissolved in water, begin to release carbon dioxide and set the liquid in motion.
Conclusion: water is heavier than oil.
Video attached .
8 .Conclusions and Conclusions:
Conclusions: for each individual experiment, you need to createthe following conditions:
one). The water temperature for each experiment should be different.
2). To perform experiments, various substances or objects may be required.
3). Some experiments require care and accuracy of execution.
4). A certain group of experiments requires the help of an adult assistant.
5). Under all conditions, all the above experiments can be performed at home.
Conclusion: water is an interesting substance for experiments, which has many different properties.
Important to remember!
The role of water in the life of our planet is amazing and has not yet been fully disclosed. It’s even scary to think about what would be the seas and oceans, lakes and rivers on earth. How would all living things develop in this case? In this case, life on our planet could not even appear. It is water that the Earth owes the emergence and development of life, therefore, if it were not for it, there would be no us. Without water, we would not know its structure, its properties, its value, its features.
Water is one of the most important natural resources any territory. The rapid growth of water consumption, pollution of rivers caused by the discharge of sewage into them, reduce the quality of water in water bodies. Lakes are polluted and overgrown. The need for drinking water in the world is constantly growing.Today, we often do not appreciate this treasure, which many feel lacking.
Though ultimately from pollution natural waters the person himself and his activities suffer. Due to these circumstances, people's health is at serious risk. Therefore, it is necessary to create all conditions for the conservation of water resources. It is necessary to rationally use water resources and prevent their pollution. Only in the presence of clean water will our civilization develop. At home, you can also purify water. I will talk about ways to purify water in the next video.
Video attached
9 .Materials used :
Experiments with water// Lessons of magic (Electronic resource).
Experiments with water for schoolchildren (Electronic resource)
Physical properties of water// All about water (Electronic resource).
Y. Perelman "Entertaining Physics".
