Presentation "properties of water". Physics presentation "the amazing properties of water" Presentation on the topic of the unusual properties of water
Water does not wet everything The molecules of a liquid are attracted to each other more strongly than to the molecules of a solid. As a result of the attractive force between the molecules of the liquid, it is collected into a droplet. This is how mercury behaves on glass, water on paraffin or greasy surfaces.
Surface tension The thermodynamic characteristic of the interface between two phases in equilibrium, determined by the work of the reversible isotherm of kinetic formation per unit area of this interface, provided that the temperature, volume of the system and the chemical potentials of all components in both phases remain constant.
Why is water the universal solvent? Water is electrically neutral. But the electric charge inside the molecule is unevenly distributed: in the region of hydrogen atoms, a positive charge prevails, in the region where oxygen is located, the negative charge density is higher. Therefore, a particle of water is a dipole. This property of the water molecule explains its ability to orient itself in an electric field and attach itself to other molecules that carry a charge. If the energy of attraction of water molecules to the molecules of a substance is greater than the energy of attraction between water molecules, then the substance dissolves.
19 states of water Scientists distinguish at least 5 different states of water in liquid form and 14 states in frozen form. no matter what you do, at -38°C even the purest super-chilled water will suddenly turn into ice. What happens as the temperature drops further? At -120°C, something strange begins to happen to water: it becomes super-viscous or viscous, like molasses, and at temperatures below -135°C, it turns into "glassy" or "glassy" water - a solid that lacks crystalline structure.
Water surprises physicists In 1995, scientists conducted a neutron scattering experiment with an unexpected result: physicists found that neutrons directed at water molecules "see" 25% fewer hydrogen protons than expected. It turned out that at the speed of one second (seconds) an unusual quantum effect takes place, and the chemical formula of water instead of H 2 O becomes H 1.5 O!
Conclusion Water cannot wet greasy surfaces Water is electrically neutral Hot water freezes faster than cold water Scientists identify 19 states of water: 5 in liquid form and 14 in frozen form At the speed of one second (seconds), the chemical formula of water instead of H 2 O becomes H 1.5 O
References D.E., Technique and production. M., 1972 Khomchenko G.P., Chemistry for applicants to universities. M., 1995 Prokofiev M.A., Encyclopedic Dictionary of a Young Chemist. M., 1982. Glinka N.L., General chemistry. Leningrad, 1984. Akhmetov N.S., Inorganic chemistry. Moscow, 1992
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PROBLEM SITUATION Water is the most important substance in the world. Without it, there would be no life on Earth. Everyone uses water every day and cannot live without it even for a week. But then we thought, how could such an ordinary object be unusual? What unusual properties does it have? What does it consist of? So, we decided to find out and figure it out. Maybe the water is not what it seems to be. The time has come to answer these questions.
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PURPOSE OF THE WORK The purpose of the work is to find out everything about water; What water consists of What properties it has What it and these properties are unusual
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RESEARCH We got acquainted with the relevant Internet sites and learned a lot about water. Like what it consists of. And it turns out that it has many amazing properties. Now we will tell you about this and many other things related to water.
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COMPOSITION OF WATER OR WHAT IS WATER A water molecule consists of two hydrogen and one oxygen atoms, which are interconnected by a covalent bond. Under normal conditions, it is a transparent liquid that has no color (with a small layer thickness), odor and taste. TERM: Water is a binary inorganic compound with the chemical formula H2O.
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STRUCTURE OF THE WATER MOLECULE Structure of the water molecule The simplest model of the water molecule accepted today is the tetrahedron. In reality, single water molecules do not exist at normal temperature and pressure. There are several hypotheses describing the structure and properties of water associates. However, a common understanding has not yet been reached.
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FACTS ABOUT WATER The chemical formula of heavy water is D₂O In science, it is customary to call water containing deuterium heavy water. Discovered in 1932 by Americans G. Urey and E. Osborne Boiling point +101.4 °C Freezing point +3.8 °C Heavy water 11% heavier than normal Heavy water has a negative effect on organisms
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AMAZING PROPERTIES OF WATER Anomalous thermal properties of water At +4 C Water at this temperature is heavier than at any other, and therefore will always sink to the bottom in a reservoir. As a result of these processes, mixing of water layers will always occur in the reservoir. And this is very important for life, since the water at the bottom of any quiet pond or lake is always poor in oxygen, and if there was no mixing of water, the inhabitants of the reservoir would begin to suffocate from its lack.
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Abnormally high heat capacity Water, when heated by one degree, absorbs 5 to 30 times more heat than any other substance. Therefore, those processes that occur in our body during intense muscular work do not cause such a high rise in temperature as it would be in the case of other liquids. AMAZING PROPERTIES OF WATER
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The ability to give off heat to the environment during evaporation. The ability to give off heat to the environment during evaporation. As you know, water, evaporating from the surface of the body of a person, animals and plants, protects them from overheating. The ability to give off heat to the environment during evaporation is inherent in any liquid. However, when scientists compared these abilities in different liquids, it turned out that water is a kind of champion of thermal conductivity here. Compared to any other substance in the liquid state, it gives off the largest amount of heat to the environment when it evaporates, which makes it the best regulator of our body temperature. Therefore, with intensive muscular work, our body does not overheat. AMAZING PROPERTIES OF WATER
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Another extremely important property of water is its exceptionally high surface tension. Molecules on the surface of water experience the action of intermolecular attraction from one side. Since the forces of intermolecular interaction in water are abnormally large, each molecule floating on the surface of the water is, as it were, drawn into the water layer. AMAZING PROPERTIES OF WATER
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The ability to expand when frozen. All substances during freezing, that is, during the transition from a liquid to a solid state, are compressed, and water, on the contrary, expands. Its volume increases by 9%. This is due to the fact that when water molecules freeze, they begin to move away from each other. As a result, the mass remains the same as it was, and the volume increases. Or in another way: if you put a liter jar of water and a liter jar of ice on the scales, the jar of water will be heavier than the same jar of ice. AMAZING PROPERTIES OF WATER
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Let's try to imagine what would happen in nature in winter if ice sank (and it should sink, because the density of all substances increases during the transition from a liquid to a solid state). Rivers, lakes, polar seas and oceans would freeze to the very bottom, and all living organisms in them would die. But, when ice forms on the surface of the water, it, being between cold air and water, prevents further cooling and freezing of water bodies. AMAZING PROPERTIES OF WATER
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Another property of water that helps us cope both with overheating of our body, and, by the way, with its hypothermia, is its abnormally high heat capacity. Water, when heated by one degree, absorbs 5 to 30 times more heat than any other substance. AMAZING PROPERTIES OF WATER
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AMAZING PROPERTIES OF WATER Another amazing property of water, which is important for the life of the entire planet, is its high latent heat of fusion. This property of water saves us from catastrophic spring floods. Due to the slow melting of ice and snow, the soil absorbs a sufficient amount of moisture and thereby prevents, in some cases, the death of plants during a drought.
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AMAZING PROPERTIES OF WATER Viscosity. And here again we are faced with something inexplicable: unlike the viscosity of other liquids, it decreases with increasing pressure. An increase in temperature also lowers the viscosity of water. This fact explains why groundwater, even at great depths at high pressures and temperatures, is quite mobile - it can move, including towards the surface of the earth, and can eventually be used by plants or humans.
"Chemical properties of water" - Pure water is a transparent liquid that has no color, taste or smell. Theoretical (analysis of articles, publications.). Therefore, water boils at about 180? With higher than should boil. Fundamental question. Moisture rises from the roots to the tops of tall trees. Ice is lighter than water (?=0.92 g/cm?).
"Substance water" - Water ... Group work Water! What kind of water do we use? Subject CHEMISTRY Performers "Theorists" - students of group 29 - PKD. Water affects the cooking and taste of food. Subject BIOLOGY, BASICS OF ECOLOGY Performers "Ecologists" - students of group 28 - PKD. Has a taste; has no taste. Water? Has an odor; has no smell.
"Water and its properties" - In fact, single water molecules do not exist at normal temperature and pressure. There are several hypotheses describing the structure and properties of water associates. Experience 1. Expansion. But water with salt in 2 hours only acquired a slight coating on the surface. The ability to give off heat to the environment during evaporation.
"Mineral waters" - Different layers of soil serve as a kind of filter. Otherwise, you can get the opposite effect of the treatment. HOW TO BE TREATED CORRECTLY? The second - to the medical-dining rooms, which cannot be overdone. It would seem that it could be simpler - minerals and gases dissolved in water. The impact of mineral waters is very diverse and affects all organs and systems.
"Physical properties of water" - Water by chemical composition can be called oxygen hydride. But water behaves differently here too. Well, who doesn't know that water freezes at 00C? H2Te, H2Se and H2S are chemical analogues of water. What is water? Dependence of boiling and freezing points on molecular weight. At what temperature does water boil?
"Properties of water" - For example, we can take coals. Water is one of the most common substances in nature. Let's deal with oxides first. 1. Reactions of water with basic oxides. Chemical properties of water. March 22 - World Water Day according to the UN calendar, Water Day. #4 Experimental Chemists Does solubility depend on temperature?
There are 13 presentations in total in the topic
Nikitin Ivan
Research work for participation in the scientific-practical conference.
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The amazing properties of water were completed by: Nikitin Ivan MBOU Gymnasium No. 4 3 "A" class
Purpose of the work To find out what properties water has and how a person uses them
Work plan Study information about water, find interesting facts in books, the Internet. Conduct experiments to study the properties of water. Find out where a person uses the considered properties of water.
Quotes about water “Water, you have no taste, no color, no smell, you cannot be described, you are enjoyed without knowing what you are. You are not only necessary for life, you are life.” Antoine de Saint-Exupery "Although there is no object in the world that would be weaker and softer than water, it can destroy the hardest object." Lao Tzu “Water is the beauty of all nature. Water is alive, it runs or is agitated by the wind, it moves and gives life and movement to everything around it. S.A. Aksakov
Interesting facts about water A person needs about 2 liters of water a day Without water, a person can only live for six days The body of an adult consists of 70% water, a child - 80% During his life a person drinks about 35 tons of water And 33 liters of water can be boiled with energy human body excreted per day Contaminated groundwater is purified over several millennia
Marvelous! The largest raindrop was 9.4 centimeters in size! Such drops fell on the USA. The longest continuous rain fell in India for almost two years! The largest hailstone weighed one kilogram and two grams! She landed in Bangladesh. The thickness of the cloud in the sky can be more than Mount Everest, its thickness can reach sixteen kilometers! An iceberg can melt for as long as ten years.
DEW POND CLOUDS SNOW FOG VAPOR HORROW WHAT WATER WE KNOW
Water properties
In order to learn more about the properties of water, I conducted a series of experiments. Will the needle sink? (surface tension) Match star Real flowers Does salt water freeze? Water expands when it freezes
Will the needle sink? (surface tension) A piece of a napkin with a needle was placed on the surface of the water With the help of another needle, the napkin was lowered to the bottom of the cup The needle remained on the surface of the water The water molecules try to be as close as possible and are attracted to each other, "pulling" the surface of the water. Surface tension keeps the needle in the water
Star from matches (capillary phenomenon) We take 5 matches, break them in half and bend them at an angle Fold them with corners towards the center This is how the figure turned out Drop a few drops of water into the center After a while, the matches straighten out, forming a star The reason for the phenomenon called capillarity is that wood fibers absorb moisture. She crawls further and further along the capillaries. The tree swells, and its surviving fibers "get fat", and can no longer bend much and begin to straighten out.
Fresh flowers We cut out flowers from colored paper We twist the petals to the center and lower them into a bowl of water After a while, the petals will begin to straighten The petals have straightened completely Paper consists of fibers. They look like very thin tubes. When the paper gets wet, the tubes fill with water and the paper swells. At the fold, the paper also swells and the petals straighten. (capillary phenomenon)
Does salt water freeze? We took two identical cups of water In the cup under the letter "B" they put a large amount of salt and put it in the freezer overnight. After standing in the freezer all night, the salt water in the cup "B" did not freeze, but ice crystals formed in the cup. The fresh water in the glass "A" turned into ice.
Water expands when it freezes. Ordinary tap water was poured into a glass ... ... and put into the freezer for the night. The next day we took out a glass of frozen water. It can be seen that the ice has risen in a tubercle. In water, the molecules move randomly, so it takes the shape of the vessel in which it is poured. Ice, on the other hand, has a clear crystalline structure, while the distances between ice molecules are greater than between water molecules, so ice takes up more space than water, that is, it expands.
What properties of water are used in everyday life In everyday life, all the properties of water that I have considered are used
What properties of water are used in industry Capillarity No form Solvent Evaporates Fluidity Colorless Odorless Tasteless
What properties of water are used in agriculture and animal husbandry Fluidity Evaporation Capillarity Solvent Surface tension Colorless Tasteless Odorless No definite form Transparent
What properties of water are used in shipping and power plants Fluidity Evaporation Surface tension Colorless, tasteless and odorless
Rest Colorless, tasteless and odorless Fluidity Surface tension
Water is the greatest human wealth The earth is 70% covered with water and the natural cycle of water is constantly maintained in nature: it evaporates from the surface of water bodies, and then falls in the form of precipitation: rain or snow. But still, some areas of the globe are constantly suffering from a lack of fresh water. That is why it is worth remembering that water is the greatest wealth given to us by nature, and every drop of it is precious, because human life is impossible without water.
While doing the work, I learned a lot of interesting things about water. But there are still many questions: What is living and dead water? What is hard water and what is soft water? Water can give life, it can also destroy How is water treated?
