Liquid bodies are examples of the world around us 3. Bodies, substances, particles. Surface tension is a property of water

Class: 3

Presentations for the lesson

Back forward

Attention! Slide previews are for informational purposes only and may not represent all the features of the presentation. If you are interested in this work, please download the full version.

Back forward

Age: 3rd grade.

Subject: Bodies, substances, particles.

Lesson type: learning new material.

Lesson duration: 45 minutes.

Lesson objectives: form the concept of body, substance, particle, teach to distinguish substances according to their characteristics and properties.

Tasks:

Introduce children to the concepts of body, matter, particle.
Teach to distinguish substances in different states of aggregation.
Develop memory and thinking.
Improve self-esteem and self-control skills.
Increase the psychological comfort of the lesson, relieve muscle tension (dynamic pauses, change of activities).
Form friendly relationships in the team.
Cultivate interest in the world around you.

Equipment:

1. Multimedia interactive presentation (Annex 1). Presentation Control Appendix 2.

2. Drawings (solid, liquid, gaseous substances).

3. Metal ruler, rubber ball, wooden cube (from the teacher).

4. For the experiment: glass, teaspoon, piece of sugar; boiled water (on children's tables).

During the classes

I. Organizational moment.

The teacher welcomes the children, checks their readiness for the lesson, addressing the students: “Today you will complete all tasks in groups. Let’s repeat the rules of working in a group” (slide No. 2).

Treatment of comrades – “politeness”;
Opinion of others - “learn to listen, prove your point of view”;
Working with sources of information (dictionary, book) - highlight the main thing.

II. Learning new material.

Setting a learning goal: today we are starting to study the topic “This Amazing Nature” - we will take a virtual excursion (slide No. 3). On the slide: a drop of water, a sugar bowl (storage container), a hammer, a wave (water), clay, metal.

The teacher asks the question “Did all the words allow you to accurately represent the subject?”

Those words that accurately help to represent an object, namely, have an outline, a shape, are called bodies. What these objects are made of are called substances.

Working with a source of information (dictionary by S.I. Ozhegov):

Write down the definition in your notebook: “Those objects that surround us are called bodies”(slide number 4).

Slide number 5. The teacher invites students to compare the pictures located on the slide: a rubber ball, an envelope, a wooden cube.

Task 1: find the commonality. All bodies have size, shape, etc.

Task 2: identify the main characteristics of bodies. Answer on slide number 6: control button “answer 2”.

Slide number 6. Pictures are triggers. The ball is round, rubber, bright. Envelope – rectangular, paper, white. The cube is wooden, large, beige.

Together with the guys we conclude: “Every body has a size, shape, color.” We write it down in a notebook.

Slide number 7. What is nature? Choose the correct answer from three answer options:

Slide number 8 – working with cards. Students have cards with pictures of bodies (objects) on their desks. We invite students to divide the cards into two groups: table, sun, tree, pencil, cloud, stone, books, chair. Let's write down the answers in our notebooks. We ask students to read the names of the bodies, this will be 1 group. On what basis did they place the words in this group? We do the same with the second group.

Correct answer:

We draw a conclusion. How we divided the words (by what principle?): There are bodies that are created by nature, and there are those that are created by human hands.

We draw up the block in a notebook (Figure 1).

Slide number 9. “Interactive feed” technique. The slide shows natural and artificial bodies. Using the scroll button, which is also a trigger, we look through natural and artificial bodies (each time you press the button, the grouped pictures change).

We consolidate the acquired knowledge with the help of the game “Traffic Light” (slides 10-12). The game is about finding the correct answer.

Slide 10. Task: find natural bodies. From the proposed bodies on the slide, you must select only natural bodies. The picture is a trigger - when pressed, a traffic light signal (red or green) appears. Sound files help students ensure they have chosen the correct answer.

Teacher. Let us remember what we talked about at the beginning. We found it difficult to accurately determine whether metal, water, and clay are bodies and came to the conclusion that they do not have exact outlines or shapes, and therefore are not bodies. We call these words substances. All bodies are made of substances. Write down the definition in your notebook.

Slide 13. On this slide we will look at two examples.

Example 1: scissors - body, what they are made of - substance (iron).

Example 2: drops of water are bodies, the substance of which the drops are made is water.

Slide number 14. Let's consider bodies that consist of several substances. For example, a pencil and a magnifying glass. On the slide we look separately at the substances that make up a pencil. To demonstrate, click on the control buttons: “graphite”, “rubber”, “wood”. In order to remove unnecessary information, press the cross.

Let's consider what substances the magnifying glass consists of. Press the triggers “glass”, “wood”, “metal”.

Slide No. 15. To reinforce this, let’s look at two more examples. What is a hammer made of? The hammer consists of iron and wood (handle). What are knives made of? Knives are composed of iron and wood substances.

Slide number 16. Consider two objects that consist of several substances. Meat grinder: made of iron and wood. Sled: made of iron and wood.

Slide 17. We conclude: bodies can consist of one substance, or they can consist of several.

Slides 18, 19, 20. “Interactive feed” technique. We show it to the students. One substance can be part of several bodies.

Slide 18. Substances consist entirely or partially of glass.

Slide 19. Substances consist entirely or partially of metal.

Slide 20. Substances consist entirely or partially of plastic.

Slide 21. The teacher asks the question “Are all substances the same?”

On the slide, click the “Start” control button. Notebook entry: all substances consist of tiny invisible particles. We introduce a classification of substances according to their state of aggregation: liquid, solid, gaseous. The slide uses triggers (arrows). When you click on the arrow, you can see a picture of particles in a given state of aggregation. Click on the arrow again and the objects will disappear.

Slide 22. Experimental part. It is necessary to prove that the particles are tiny, invisible to the eye, but retaining the properties of the substance.

Let's do an experiment. On the students' tables are trays with a set of simple laboratory equipment: a glass, a spoon for stirring, a napkin, a piece of sugar.

Place a piece of sugar in a glass and stir until completely dissolved. What are we seeing? The solution has become homogeneous, we no longer see a piece of sugar in a glass of water. Prove that there is still sugar in the glass. How? To taste. Sugar: a white substance that tastes sweet. Conclusion: after dissolution, sugar did not cease to be sugar, because it remained sweet. This means that sugar consists of tiny particles invisible to the eye (molecules).

Slide 23. Let's consider the arrangement of particles in substances with a solid state of aggregation. We demonstrate the location of particles and matter (examples) using the “interactive tape” technique - the scroll button allows you to show the pictures the required number of times. We write down the conclusion in our notebook: in solids, particles are located close to each other.

Slide 24. Arrangement of particles in liquid substances. In liquid substances, particles are located at some distance from each other.

Slide No. 25. The arrangement of particles in gaseous substances: the particles are located far from each other, the distance between them significantly exceeds the particle size itself.

Slide 31. It's time to summarize. Together with the teacher, they remember what they learned new in the lesson. The teacher asks questions:

Everything that surrounds us is called... bodies
There are bodies natural And artificial.
Write down the diagram in your notebook. Teacher: Let's look at the diagram. Bodies can be natural and artificial, substances can be solid, liquid, gaseous. Substances are made up of particles. The particle retains the properties of the substance (remember that sugar remained sweet when dissolved). The slide uses triggers. Click on the “Body” shape, arrows appear, then shapes labeled “Artificial” and “Natural”. When you click on the “substance” figure, three arrows appear (liquid, solid, gaseous).

Slide number 30. Fill out the table. Read the instructions carefully.

(Mark with “ + ” in the corresponding column, which of the listed substances are solid, liquid, gaseous).

Substance	Solid	Liquid	Gaseous
Salt
Natural gas
Sugar
Water
Aluminum
Alcohol
Iron
Carbon dioxide

Checking the progress of the work (slide 30). Children take turns naming the substance and explaining which group it belongs to.

Lesson summary

1) Summing up

You worked together.

Let's find out which group was the most attentive in the lesson. The teacher asks the question: “What are called bodies, what characterizes a body, give an example.” Students answer. Everything that surrounds us is called bodies. What are the types of substances based on their state of aggregation: liquid, solid, gaseous. What do substances consist of? Give examples of how particles retain the properties of substances. For example, if we add salt to soup, how do we know that the properties of the substance have been preserved? To taste. Fill out the diagram (Figure 2)

Discussion: what we agree with, what we disagree with.

What new did you learn? Children report. ( All objects surrounding us are called bodies. Bodies are made up of substances. Substances are made from particles).

Homework

The teacher tells the children their homework (optional):

solve a small test (Appendix 5).
interactive test (Appendix 3).
view presentation about water (Appendix 7). In the presentation you can get acquainted with six well-known facts about water. Think, guys, why do you need to get to know this substance better? Answer: the most common substance on Earth. What other substance would you like to invite to your place (creating virtual excursions).
study the electronic textbook (Appendix 4).

Note: the teacher can additionally use slides No. 32, 33, 36.

Slide number 32. Task: test yourself. Find products (interactive test).

Slide number 33. Task: test yourself. Find living and inanimate bodies (interactive test).

Slide number 36. Task: divide bodies into bodies of animate and inanimate nature (interactive test).

Literature.

Gribov P.D. how a person explores, studies, uses nature. 2-3 grades. Volgograd: Teacher, 2004.-64 p.
Maksimova T.N. Lesson developments for the course “The World around us”: 2nd grade. - M.: VAKO, 2012.-336 p. - (To help the school teacher).
Reshetnikova G.N., Strelnikov N.I. The world. Grade 3: entertaining materials. - Volgograd: Teacher, 2008. - 264 pp.: ill.
Tikhomirova E.M. Tests on the subject “The world around us”: 2nd grade: for the educational set A.A. Pleshakova “The world around us. 2nd grade.” - M.: Publishing house “Exam”, 2011. - 22 p.

Bodies, substances, particles

Any object, any living creature can be called a body. A stone, a lump of sugar, a tree, a bird, a wire - these are bodies. It is impossible to list all the bodies; there are countless of them. The sun, planets, and the moon are also bodies. They are called celestial bodies.

Bodies can be divided into two groups.

Bodies created by nature itself are called natural bodies.
Bodies created by human hands are called artificial bodies.

Look at the pictures. Under natural bodies, fill in the circles with green, under artificial bodies, with brown.

Bodies are made up of substances. A piece of sugar is a body, and sugar itself is a substance. Aluminum wire is the body, aluminum is the substance. There are bodies that are formed not by one, but by several or many substances.

Substances- this is what bodies are made of.

Distinguish between solid, liquid and gaseous substances.
Sugar, aluminum are examples of solids. Water is a liquid substance. Air consists of several gaseous substances (gases).

Write down what substance the body is made of.

Which body has a certain shape?
Answer: Solids have a constant shape.

Fill out the table

Aluminum, silver, notebook, wood, TV, kettle, water, saw, wardrobe, starch.

Substances, and therefore bodies, consist of particles.
Each substance consists of special particles that differ in size and shape from the particles of other substances.
Scientists have found that there are gaps between particles. In solids these gaps are very small, in liquids they are larger, and in gases they are even larger. In any substance, all particles move.
Particles can be represented using models, such as balls.

H2O - water, Liquid metal - mercury! The liquid state is usually considered intermediate between a solid and a gas: a gas retains neither volume nor shape, but a solid retains both.

The shape of liquid bodies can be determined entirely or partly by the fact that their surface behaves like an elastic membrane. So, water can collect in drops. But a liquid is capable of flowing even under its stationary surface, and this also means that the form (internal parts of the liquid body) is not preserved.

Liquid molecules do not have a definite position, but at the same time they do not have complete freedom of movement. There is an attraction between them, strong enough to keep them close.

A substance in a liquid state exists in a certain temperature range, below which it turns into a solid state (crystallization occurs or transformation into a solid-state amorphous state - glass), above which it turns into a gaseous state (evaporation occurs). The boundaries of this interval depend on pressure.

As a rule, a substance in the liquid state has only one modification. (The most important exceptions are quantum liquids and liquid crystals.) Therefore, in most cases, a liquid is not only a state of aggregation, but also a thermodynamic phase (liquid phase).

All liquids are usually divided into pure liquids and mixtures. Some mixtures of liquids are of great importance for life: blood, sea water, etc. Liquids can act as solvents.
[edit]
Physical properties of liquids
Fluidity

The main property of liquids is fluidity. If an external force is applied to a section of a liquid that is in equilibrium, then a flow of liquid particles arises in the direction in which this force is applied: the liquid flows. Thus, under the influence of unbalanced external forces, the liquid does not retain its shape and relative arrangement of parts, and therefore takes the shape of the vessel in which it is located.

Unlike plastic solids, a liquid does not have a yield limit: it is enough to apply an arbitrarily small external force for the liquid to flow.
Volume conservation

One of the characteristic properties of a liquid is that it has a certain volume (under constant external conditions). Liquids are extremely difficult to compress mechanically because, unlike gases, there is very little free space between the molecules. The pressure exerted on a liquid enclosed in a vessel is transmitted without change to each point in the volume of this liquid (Pascal’s law is also valid for gases). This feature, along with very low compressibility, is used in hydraulic machines.

Liquids generally increase in volume (expand) when heated and decrease in volume (contract) when cooled. However, there are exceptions, for example, water contracts when heated, at normal pressure and at temperatures from 0 °C to approximately 4 °C.
Viscosity

In addition, liquids (like gases) are characterized by viscosity. It is defined as the ability to resist the movement of one part relative to another - that is, as internal friction.

When adjacent layers of liquid move relative to each other, collisions of molecules inevitably occur in addition to that caused by thermal motion. Forces arise that inhibit orderly movement. In this case, the kinetic energy of ordered movement turns into thermal energy - the energy of chaotic movement of molecules.

The liquid in the vessel, set in motion and left to its own devices, will gradually stop, but its temperature will increase.

Class 2 dangerous goods include pure gases, mixtures of gases, mixtures of one or more gases with one or more other substances, as well as products containing such substances. Substances and products of class 2 are divided into compressed gas; liquefied gas; refrigerated liquefied gas; dissolved gas; aerosol sprays and small containers containing gas (gas cartridges); other products containing gas under pressure; non-pressurized gases subject to special requirements (gas samples). Transporting Class 2 dangerous goods involves the risk of explosion, fire, suffocation, frostbite or poisoning.

Air- a natural mixture of gases consisting by volume of 78% nitrogen, 21% oxygen, 0.93% argon, 0.3% carbon dioxide and very small amounts of noble gases, hydrogen, ozone, carbon monoxide, ammonia, methane, sulfur dioxide and others. Density of liquid air 0.96 g/cubic. cm (at -192°C and normal pressure). Air is necessary for many processes to occur: combustion of fuel, smelting of metals from ores, industrial production of various chemical compounds. Air is also used to produce oxygen, nitrogen and noble gases; as a refrigerant, heat and sound insulating material, working fluid in electrical insulating devices, pneumatic tires, jet and spray devices, pneumatic machines, etc.

Oxygen- a chemical element with pronounced oxidizing properties. Oxygen is mainly used in medicine. In addition to medicine, oxygen is used in metallurgy and other industries, and liquid oxygen serves as an oxidizer for rocket fuel.

Propane– a colorless, flammable, odorless, explosive gas contained in natural and associated petroleum gases, in gases obtained from CO and H2, as well as during oil refining. Propane has a negative effect on the central nervous system; if liquid propane comes into contact with the skin, frostbite can occur.

Nitrogen- colorless gas, tasteless and odorless. Nitrogen is used in many industries: as an inert medium in various chemical and metallurgical processes, for filling free space in mercury thermometers, when pumping flammable liquids, etc. Liquid nitrogen is used in various refrigeration units. Nitrogen is used for the industrial production of ammonia, which is then processed into nitric acid, fertilizers, explosives, etc.

Chlorine- poisonous gas of yellow-green color. The main quantities of chlorine are processed at the site of its production into chlorine-containing compounds. Chlorine is also used for bleaching cellulose and fabrics, for sanitary needs and chlorinating water, as well as for chlorinating some ores to extract titanium, niobium, zirconium, etc. Chlorine poisoning is possible in the chemical, pulp and paper, textile, pharmaceutical industries, etc. d. Chlorine irritates the mucous membranes of the eyes and respiratory tract; often, a secondary infection joins the primary inflammatory changes. The concentration of chlorine in the air is 500 mg/m3. m. with fifteen minutes of exposure is fatal. In order to prevent poisoning, it is necessary: sealing production equipment, effective ventilation, and, if necessary, using a gas mask.

Ammonia- colorless gas with a sharp characteristic odor. Ammonia is used to produce nitrogen fertilizers, explosives and polymers, nitric acid, soda and other chemical products. Liquid ammonia is used as a solvent. In refrigeration technology, ammonia is used as a refrigerant (717). Also, a 10% ammonia solution (ammonia) is widely used in medicine. According to its physiological effect on the body, it belongs to the group of substances with asphyxiating and neurotropic effects, which, if inhaled, can cause toxic pulmonary edema and severe damage to the nervous system. Ammonia has both local and resorptive effects. Ammonia vapors strongly irritate the mucous membranes of the eyes and respiratory organs, as well as the skin, causing excessive lacrimation, eye pain, chemical burns of the conjunctiva and cornea, loss of vision, coughing attacks, redness and itching of the skin. When liquefied ammonia and its solutions come into contact with the skin, a burning sensation occurs, and a chemical burn with blisters and ulcerations is possible. In addition, liquefied ammonia absorbs heat when it evaporates, and when it comes into contact with the skin, frostbite of varying degrees occurs.

Svetlana Viktorovna Politova, chemistry teacher at State Budgetary Educational Institution Secondary School No. 1352 with in-depth study of the English language in Moscow.

Lesson summary.

Subject: Bodies, substances, particles.

Teacher: Politova Svetlana Viktorovna.

Lesson type: learning new material.

Lesson duration: 45 minutes.

Lesson objectives:

Form the concept of body, substance, particle, teach to distinguish substances according to their characteristics and properties.

Introduce children to the concepts of body, matter, particle.

Teach to distinguish substances in different states of aggregation.

Introduce the concept of mixtures and pure substances.

Test students' knowledge on the topic covered.

Develop memory and thinking.

Improve self-esteem and self-control skills.

Increase the psychological comfort of the lesson, relieve muscle tension (dynamic pauses, change of activities).

Form friendly relationships in the team.

Cultivate interest in the world around you.

Equipment:

1. Multimedia interactive presentation.

1. Drawings (solid, liquid, gaseous substances).

2. Metal ruler, rubber ball, wooden cube (from the teacher).

3. For the experiment: glass, teaspoon, piece of sugar; boiled water (on children's tables).

During the classes

Organizing time

The teacher welcomes the children, checks their readiness for the lesson, addressing the students: “Today you will complete all tasks in groups. Let’s review the rules of working in a group” (slide No. 2).

Treatment of comrades - “politeness”;

Opinion of others - “learn to listen, prove your point of view”;

Working with sources of information (dictionary, book) - highlight the main thing.

Learning new material

Setting a learning goal: today we are starting to study the topic “This Amazing Nature” - we will take a virtual excursion (slide No. 3). The slide shows pictures:

water drop

sugar bowl

(storage container)

wave (water)

The teacher asks the question “Did all the words allow you to accurately represent the subject?”

Those words that accurately help to represent an object, namely, have outlines and shapes, are called bodies. What these objects are made of are called substances.

Working with a source of information (dictionary by S.I. Ozhegov):

The body is a separate object

in space, as well as part of space filled with matter, some substance...

Body - the human or animal organism in its external, physical forms.

The body is a part of the organism...

Body - the main part, the body of something.

Write down the definition in your notebook: “Those objects that surround us are called bodies"(slide number 4).

Slide number 5. The teacher invites students to compare the pictures located on the slide: a rubber ball, an envelope, a wooden cube.

Task 1: find the commonality. All bodies have size, shape, etc.

Task 2: identify the main characteristics of bodies. Answer on slide number 6: control button “answer 2”.

Slide number 6. Pictures are triggers. The ball is round, rubber, bright. Envelope – rectangular, paper, white. The cube is wooden, large, beige.

Together with the guys we conclude: “Every body has a size, shape, color.” We write it down in a notebook.

Slide number 7. What is nature? Choose the correct answer from three answer options:

Anything made by human hands

Everything that surrounds us

Everything that surrounds us and exists independently of man

Slide number 8 – working with cards. Students have cards with pictures of bodies (objects) on their desks. We invite students to divide the pictures into two groups: table, sun, tree, pencil, cloud, stone, books, chair. Make a note in your notebook. We ask students to read the names of the bodies, this will be 1 group. On what basis did they place the words in this group? We do the same with the second group.

Correct answer:

Artificial

Natural

pencil

We draw a conclusion. How we divided the words (by what principle?): There are bodies that are created by nature, and there are those that are created by human hands.

We draw up the block in a notebook.

We consolidate the acquired knowledge with the help of the game “Traffic Light” (slides 10-12). The game is about finding the correct answer.

Flowers

Bird

Slide 11. Task: find artificial bodies.

Bed

Hat

Bag

Slide number 12. Task: find artificial bodies.

Alarm

Car

Slide 13. On this slide we will look at two examples.

Example 1: scissors - body, what they are made of - substance (iron).

Example 2: drops of water are bodies, the substance of which the drops are made is water.

Let's consider what substances the magnifying glass consists of. We press the triggers “glass”, “wood”, “metal”.

Slide No. 15. To reinforce this, let’s look at two more examples. What is a hammer made of? The hammer consists of iron and wood (handle). What are knives made of? Knives are made of iron and wood.