The role of water in nature - presentation. Presentation - water cycle in nature Aquatic environment water in nature presentation

Water (hydrogen oxide) is a binary inorganic compound, chemical formula H 2 O. A water molecule consists of two hydrogen atoms and one oxygen, which are connected by a covalent bond. Under normal conditions, it is a transparent liquid, colorless (in small volumes), odor and taste.

Distribution of water On Earth, approximately 96.5% of the world's water is in the oceans, 1.7% of the world's reserves are groundwater, another 1.7% in glaciers and ice caps in Antarctica and Greenland, a small portion in rivers, lakes and swamps, and 0.001% in clouds (formed from particles of ice and liquid water suspended in the air). An interesting fact is that the Earth’s mantle contains several times more water than the amount of water in the World Ocean.

Three aggregate states of water Liquid Gaseous Solid Water on Earth can take on various forms that can simultaneously coexist with each other: water vapor and clouds in the sky, sea water and icebergs, glaciers and rivers on the surface of the earth, aquifers in the ground.

High Specific Heat Capacity Water has the highest specific heat capacity. A physical quantity numerically equal to the amount of heat that must be transferred to a body weighing 1 kg in order for its temperature to change by 1 °C is called the specific heat capacity of a substance.

The main climate thermoregulator Due to its high heat capacity, water in the seas and oceans, when heated in summer, absorbs a large amount of heat. Therefore, in areas located near water bodies, it is not very hot in summer and very cold in winter. This is due to the fact that in winter the water cools and gives off a large amount of heat.

Water vapor The optical properties of water vapor play a significant role in plant life. The fact is that water vapor strongly absorbs infrared rays with a wavelength of 5.5 to 7 microns, which is important for protecting the soil from frost. An even more effective remedy for frost is dew and the formation of fog: moisture condensation is accompanied by the release of a large amount of heat, which delays further cooling of the soil.

Biological role Water plays a unique role as a substance that determines the possibility of existence and the very life of all creatures on Earth. The human body consists of 70-80% water, some plants contain up to 90% or more water. On average, the body of plants and animals contains more than 50% water

Universal solvent Water acts as a universal solvent in which the basic biochemical processes of living organisms occur. Each molecule of the solute is surrounded by water molecules, and the positively charged parts of the molecule of the solute attract oxygen atoms, and the negatively charged hydrogen atoms. Since a water molecule is small in size, many water molecules can surround each solute molecule.

Water is of key importance in the creation and maintenance of life on Earth, in the chemical structure of living organisms, in the formation of climate and weather. It is the most important substance for all living beings. Water is necessary for the life of all unicellular and multicellular living beings without exception. Without water there would be no life on Earth.

Used literature and website materials: baltecopool.ru dic.academic.ru teme-mirovoy-okean-tixii/ teme-mirovoy-okean-tixii/ Water-Posters_i _.htm Water-Posters_i _.htm ru.wikipedia.orgWater Physics. 8kl. : textbook for general education institutions / A. V. Peryshkin.

Abstract "Water on Earth" (with introspection)

Geography teacher MKOU Secondary School No. 21

Lesson objectives:

To consolidate knowledge about the atmosphere - introduce the three states of water and its properties; - develop a careful attitude towards the water resources of our planet.

Equipment: - a globe, - a physical map of the hemispheres, - a poster with a rebus and the properties of water, - glasses of water and milk for experiments, salt, sugar, a spoon, - children's drawings about water in nature

Educational film "Hymn to Nature"

Presentation "Water in Nature"

Lesson preparation:

It is written on the board: number. Each child has a printed notebook prepared for checking their homework.

During the classes

1. Checking homework.

We check workplace equipment .

The officers on duty check the weather calendars.

a) Conversation.

What topic did we study in previous lessons? -Open the textbook on pages 78-79 and work with questions according to the rubrics.

b) Individual work in a workbook. The teacher reads each task, and the children fill out a workbook.

At the end of work there will be a physical education session.

2. Setting the goal of the lesson.

It is difficult for us to live without many minerals. But there is one wealth that is absolutely impossible to do without. What kind of wealth this is, we learn from the riddle.

• “What can’t be rolled up a mountain, carried away in a sieve, or held in one’s hands?” (Water).
• Why can’t we roll it up the mountain? (Flows from top to bottom)
• Why can’t you carry it away in a “sieve”? (It will leak through the holes)
• Why can’t you hold it in your hands? (It will pour out)

Today in class we will talk about water. The topic of our lesson is “Water on Earth”. (The teacher writes the topic on the board, and the children in their notebooks).

3. Explanation of new material.

A). The role of water in the life of humans, plants and animals.

Guys, what role does water play in human life? Why and why is it necessary? How does a person use water? (Washes, drinks, cooks, washes dishes, floors, laundry, bathes, in heating systems, etc.).

Human blood consists of 98% water, human muscles - 70% water, and in general the human body, brain, body tissues are more than half made of water. A lack of water is more dangerous for a person than starvation: a person can live more than one month without food, but only a few days without water. A person consumes from 3 to 6 liters of water per day (depending on the climate).

Water is necessary for both animals and plants. All plants “drink” water and receive the necessary substances for growth and development. Water is contained in the root, leaves, trunk, and bark of a tree.

For example, to grow 1 kg of potatoes, 300 liters of water are needed.

Without water, plants wither and may die. Animals also need water to live.

What conclusion can we draw?

Conclusion: All plants, animals, and people need water for nutrition and cooling. Without water there will be no life.

b) Water forms the water shell of our planet - the hydrosphere (from the Greek words “gyra” - water, “sphere” - ball.

In front of you is a globe - a model of the Earth. It has the same symbols as on the map. Remember what the colors blue and cyan mean? (Water). Green and brown? (Plains and mountains).

On the globe these are continents or land. I spin the globe around its axis. Which color is dominant? (blue). What follows from this?

On Earth, most of the water spaces are occupied by the oceans: the Pacific, Atlantic, Indian and Arctic. (The teacher shows the oceans on the map, the children show on the map in the textbook p. 82-83).

Draw a diagram on the board:

Three quarters of the globe is occupied by water.

4. “Water in nature” presentation demonstration.

Guys. Have you now seen where water can be found in nature? (Rivers, lakes, seas, springs, wells, puddles, dew, rain, fog, clouds, ice, snow, hail, frost)

5. Three states of water.

You said that cloud (fog), dew, snow are water. But somehow it is different in dew, snow, fog. How is it different? (Cloud, fog is steam (water in the form of steam), dew is water in liquid form, snow is water in solid form, crystals).

What kind of substance is water: liquid, solid or steam?

Conclusion. Water is a special mineral because it can be in three states at the same time.

A diagram is drawn on the board and in notebooks.

Give examples where at home you can see water in the form of liquid (from the tap), in the form of steam (cooking food - steam), in solid form (in the refrigerator)?

I wonder if water can go from liquid to vapor? (Yes).

Under what conditions will this happen faster? (It needs to be heated).

And from liquid to solid? (Cool).

And vice versa from solid to liquid? (We need to heat it up, because ice and snow melt in warmth).

How about going from a solid state to a vapor? (Yes)

Give examples. (In winter, my mother dries her laundry on the balcony. It immediately freezes, that is, liquid water becomes ice, but still it dries out (almost), therefore, solid water can turn into steam.)

Can steam become a liquid again or become a solid? (Yes, if you cool it down. Clouds, drops in the bathroom on the ceiling, hail).

Conclusion: Water is a wonderful mineral. It can be in three states at once and move from one to two others. There is no other mineral like this!

Properties of water.

Let's look at the properties of water and determine what properties it has.

On the board there is a poster “Properties of water”. The listed properties are revealed gradually as they are determined as a result of experiments.

What word is encrypted? How did you guess?

Let's conduct experiments and figure out what properties of water are hidden on the poster.

Experience No. 1. What will happen to water if I drop it on glass? (Spread)

Water doesn't hold its shape. I'll pour water from the jar into a glass. What form did the water take? (Shape of a glass).

Conclusion: Water has no form and takes the form of the vessel into which it is poured.

What property of water allowed us to pour it from a jar into a glass? (Fluidity).

Experience No. 2. Two glasses - with milk, with water, a spoon. What can you say about the color of milk? (White) What about water? (colorless) Immerse the spoon in a glass of water. The spoon is visible from all sides.

Conclusion: Therefore, the water is clear.

Experience No. 3. I take sugar and salt. Which one is a mineral? (Salt) Why not sugar? (Manufactured by humans). I put sugar and salt into glasses with water, spoonfuls at a time, and stir. What happened to salt and sugar? (Melted) Why? (Water dissolved them)

Conclusion: Water is a universal solvent. It completely dissolved the salt and sugar and remained transparent. For example, one liter of ocean water contains on average 35 grams of salt (mostly table salt), which gives it a salty taste and makes it unsuitable for drinking and use in industry and agriculture.

Experience No. 4. If we smell plain water, what does it smell like? What about the taste?

Conclusion: The water is odorless and tasteless.

Which water tastes better: rainwater, tap water or spring water? Why? You said that water has no taste.

Rain water does not have the salts the body needs, so it seems tasteless. Tap water is poorly purified; filters are needed - means for water purification. Rodnikovaya- dissolves minerals underground, passes through sand (natural filter), but it is better to boil before use.

How is mineral water different from regular water?

Fairy tales often talk about living and dead water. Most likely, these fairy tales were born from life. Is there really water that has life-giving, healing powers?

Student's story about mineral water (advanced task). Regional component.

Distribution of water on Earth (drawing in the textbook p. 80)

6. Careful attitude towards water.

There is a lot of water on Earth, but clean water is becoming less and less. This is not because water supplies are depleting. And why? The threat of pollution looms over the water. Who is polluting it?

Plants, factories, hydroelectric power stations consume large amounts of water and at the same time pollute it with various waste products. Various toxic substances enter rivers and lakes with waste (used) water from enterprises. Life, fish, plants, animals die in water. Decaying waters poison the air and become a source of serious diseases. The river is “sick”; its waters cannot be used by humans.

We must save water! By taking care of the purity of water, we take care of our health and the beauty of the surrounding nature. Our country has adopted a number of laws aimed at protecting waters. Their implementation is monitored by government authorities and environmentalists.

How can you guys take care of the cleanliness of water bodies? (Do not throw cans, bottles, or other garbage. Use water sparingly).

You can show posters and drawings calling for saving water.

“Close the tap tightly so the ocean doesn’t leak out.” “Pour water sparingly, know how to value water.”

7. Students read poems and show their drawings.

We study the hydrosphere,

We answer questions.

Water - mineral, water - ash - two - oh,

Water is above all else in the Universe.

Let me ask you then

What state is water in?

/ Students’ answers - in solid, liquid and gaseous./

The little neighbor asked the other day

At the stream pouring from the tap:

Where are you from?

Water in response:

From afar;

From the ocean!

Then the baby walked in the forest

The whole clearing sparkled with dew

Where are you from?

I asked Dew.

Believe me too

From the ocean!

A gray fog lay on the field

The kid asked the fog too

Where are you from?

Both me and I are a friend from the ocean!

Amazing isn't it?

In soup, tea, in every drop,

In a ringing piece of ice

And in the rain,

And in the dewdrop and in the river

Will always respond to us

Ocean water!

8. Work according to the textbook(pp.80-81, pp.84-85)

9. Summing up the lesson - presentation “Water in Nature”.

Local history material

Cold, hot, fresh and mineral underground waters are common in our region. 12 types of Mineral water from our region are known all over the world.

The waters of Pyatigorye are unique natural underground factories of medicines.

In the cracks of failed volcanoes, water accumulates, saturated with hot solutions and gases coming from deep pockets of frozen magma, and then rushes to the earth's surface, forming dozens of springs at the foot of the mountains.

Our area has underground interstratal waters:

thermal, fresh, salt and mineral.

Thermal waters have a temperature of 90 degrees, with a very high salt content, these waters are still little used.

Mineral waters have not been fully studied and taken into account, but the local population has been using them for a long time. In the area of ​​the village of Podgornaya there is a spring that treats skin diseases,

In the village of Nezlobnaya and in the area of ​​the Georgievsky flour mill there are springs that treat the gastrointestinal tract. In the area of ​​Mount Lysaya there are diseases of the musculoskeletal system. In the area of ​​the city lake, a hydropathic clinic was built, using iodine-bromide waters