The subject of chemistry. Substances and their physical properties. Presentation on the topic "Subject of chemistry. Substances" Natural sciences

slide 4

Task: Show the winning path that the names make up:

2) substances

slide 5

Questions: 1. What particles are shown in the pictures? 2. How many particles are shown? 3. Count the number of chemical elements. 4. Which of the pictures shows simple substances? How many? 5. Where are complex substances depicted? How many?

slide 6

Task: Arrange the terms as the particle size increases:

molecule electron atom atomic nucleus

Slide 7

Task: Move the drawings depicting atoms and molecules to the corresponding concepts

Chemical element Free atoms Complex substances Simple substances

Slide 8

Simple substances

Sulfur Bromine Properties of substances Phosphorus Copper Mercury Sodium

Slide 9

Complex Substances

Quartz Properties of substances Table salt Zinc blende Water Brown gas

Slide 10

Properties of substances

Get five cents! Find the properties of copper! Task thermally conductive Red-brown Metallic luster liquid gas light electrically conductive smooth hard soft stable malleable plastic Answer

slide 11

And collect a pound of salt! You go up the stairs, Find the properties of salt! Task Water-soluble refractory Glass luster liquid gaseous free-flowing solid tasty white soft malleable viscous Answer

slide 12

Homework

§1,2, entries in exercise book. 3,4 Using a sheet of cardboard and small transparent bags, assemble a collection of simple or complex substances used in everyday life.

slide 13

List of used literature.

O.S. Gabrielyan handbook for a teacher of chemistry. 8th grade. M. "Blik plus", 2000 O.S. Gabrielyan Chemistry - 8, M. Bustard, 2007 O.S. Gabrielyan, T.V. Smirnova. We study chemistry in the 8th grade. M. "Blik plus", 1997 CD Electronic lessons and tests "Substances and their transformations"

Slide 14

Links to used images

Image of copper http://upload.wikimedia.org/wikipedia/commons/d/dc/Copper_crystals.jpg Image of quartz http://upload.wikimedia.org/wikipedia/commons/c/ce/Quartz_Brésil.jpg Image of sulfurhttp:/ /upload.wikimedia.org/wikipedia/commons/4/44/Sulfur-sample.jpg Picture of phosphorus http://upload.wikimedia.org/wikipedia/commons/8/88/PhosphComby.jpg Picture of mercury http://upload. wikimedia.org/wikipedia/commons/9/99/Pouring_liquid_mercury_bionerd.jpg Image of bromine http://upload.wikimedia.org/wikipedia/commons/b/bd/Brom_amp.jpg Image of brown gas http://upload.wikimedia.org/wikipedia /commons/3/31/Diossido_di_azoto.jpg Picture of sodium chloride http://upload.wikimedia.org/wikipedia/commons/e/ea/Halit-Kristalle.jpg Picture of zinc blende http://upload.wikimedia.org/wikipedia/commons /2/2f/Sphalerite4.jpg Water Image http://upload.wikimedia.org/wikipedia/commons/f/fd/Splash_2_color.jpg

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Ideal task Level 1. Compare the physical properties of: a) mercury and aluminum; b) copper and zinc; c) chalk and coal. Level 2. According to what two most characteristic signs is it enough to oppose two substances: a) mercury and aluminum; b) copper and zinc; c) chalk and coal. Level 3. What are the most well-known uses of the following substances: a) glass, b) aluminum? The presence of what properties can be considered a disadvantage in this practical application of them?

Chemistry is a miracle science! In any area stretches out his hands! Chemistry in clothing, food and water, In the home, in the air, everywhere! The color of the liquid will quickly change, The fire will spread without a match, The natural product will replace The person needs to know her habits! Agriculture, medicine, space... There is a demand for chemistry everywhere. We will teach it from now on and until the century, After all, chemistry is also the human body. Call her a maid or a queen, It's not about the name, Our whole life is the knowledge of chemistry. exit

To help the teacher Slide 2. The teacher begins the lesson with an introductory conversation, emphasizing that at present it is impossible to imagine life without chemistry and the chemical industry. Modern chemistry has penetrated into all areas of the national economy. “Chemistry spreads its hands widely in human affairs. Wherever we look, wherever we look back - everywhere the successes of its application turn before our eyes, ”M.M. Lomonosov back in 1751. Next, the topic of the lesson and its objectives are announced. Slide 3. Reflection. The teacher asks students to assess their readiness to receive new information. Slide 4. The teacher asks questions: - What are called bodies? What properties do bodies have? - What is a substance? Then he clarifies these concepts. Introduces a clear distinction between the concepts of "substance", "body". Shows samples of granite, indicating that the body may be composed of several substances. Slide 5. The teacher invites students to complete the task: distribute the names of bodies and substances into columns. Then it does a self test. Slide 6. The teacher asks the question: - What properties do substances have? Next, the teacher organizes work according to the scheme "The most important physical properties of substances"

Slide 7. The teacher invites students to choose a feature by which the proposed substances can be distributed. Students note this sign and distribute substances according to their state of aggregation. Cross-checking is underway. Slide 8. Vision correction is being carried out. Slide 9. Noting the variety of known and newly obtained substances, the teacher explains the difference and similarity of substances in properties. Draws students' attention to the fact that it is possible to compare substances if the main features of comparison are highlighted. Next, the teacher organizes work on filling out the table "Comparison of the properties of substances." They draw a conclusion about the first task of chemistry. Slide 10. After discussing examples of transformations of substances, the students, together with the teacher, draw a conclusion about the second problem of chemistry and define chemistry as a science. Slide 11. The teacher offers students to complete one of the tasks of their choice: Level 1 (lowest). Compare the physical properties of: a) mercury and aluminum, b) copper and zinc, c) chalk and coal. Level 2 (medium). According to what two most characteristic signs is it enough to contrast two substances (see the first question)? Level 3 (highest). What properties are associated with the known use of the following substances: a) glass, b) aluminum. The presence of what properties can be considered a disadvantage in this practical application of them? Slide 12.13. the teacher shows the role of chemistry in scientific and technological progress. Reads a poem, accompanied by color illustrations. Addresses environmental issues.

Stage 1 - mythological thinking

Stage 2 - the formation of scientific knowledge (ancient Greek natural philosophy)

Heraclitus: "The world is one of everything, not created by any of the gods and by any of the people, it is an eternal fire, naturally igniting and naturally fading."

Empedocles (490-430 BC) - 4 elements (fire, water, air, earth) and 2 forces (love and enmity).

Aristotle (384-322 BC) - the unity of opposites began: dryness and humidity, heat and cold. Combining with each other, these principles form 4 elements of Empedocles.

Francis Bacon (1561-1626) English philosopher. The main method of studying chemistry should be EXPERIMENT.

Antoine Lavoisier towards the end of the 18th century. Completed the so-called. "chemical revolution". Since that time, chemistry has been considered the science of obtaining and properties of simple and complex substances.

Which row contains only substances?

salt, sugar, candle

Water, iron, sulfur

Copper, nail, oxygen

Brick, baking soda, ceramic glass

1) Table salt, sugar, candle

2) Water, iron, sulfur

3) Copper, nail, oxygen

4) Brick, copper coin, ceramic glass

Write down the names of the substances from the list: nail, glass, graphite, ruler, aluminum, iron, funnel, starch, acetic acid, glucose.

State of aggregation

Density

Solubility

Melting and boiling point

Electrical conductivity

Lesson motto:

"Chemistry stretches its hands wide in the affairs of men"

M.V. Lomonosov

www.pmedia.ru

The purpose of the lesson:

meet to

• - the subject of chemistry;
• - simple and complex substances;
• -properties of substances;
• - forms of existence of a chemical element.

natural sciences

1 . What sciences study nature?

2. What does biology study; physics; geography; astronomy; geology?

3. Why did you start studying physics in the 7th grade and chemistry in the 8th grade?

What does chemistry study?

CHEMISTRY STUDIES

SUBSTANCES

"Father of Chemistry" Robert Boyle (1627 - 1691)

PROPERTIES SUBSTANCES

TRANSFORMATIONS SUBSTANCES

Chemistry - the science of substances properties and transformations.

Body

Substance

molecules

atoms

Substance – is what physical bodies are made of Chemical element is a certain type of atom

Substances

Substances

Simple

(hydrogen,

oxygen)

Complex

(water, sugar)

Natural

(carbonic

gas)

Synthetics

cal

(polyethylene)

Consider molecular models. What are the similarities and differences between them? Which of the substances is simple and which is complex? Why?

• Substances

Hydrogen

Water

Oxygen

Forms of existence chemical elements

simple substance

complex substance

Substances that are formed by atoms of one chemical element are called simple

Substances that are formed by atoms of different chemical elements are called complex

Properties of substances

Physical

Chemical

• state of aggregation
• smell
• solubility in water
• thermal conductivity
• electrical conductivity
• density

• ability to react with other substances

Liquid substances

Sulphuric acid

Vegetable oil

Gaseous substances

Oxygen

Carbon dioxide

Exercise #1

Determine which of the proposed substances is simple and which is complex.

Properties

Compound

Chemistry

Application

Properties of substances are signs by which substances differ from each other or are similar to each other.

Exercise #2

• Indicate where oxygen is spoken of as a chemical element, and where - as a simple substance:
• A) oxygen is slightly soluble in water;
• B) water molecules consist of two hydrogen atoms and one oxygen atom;
• C) the air contains 21% oxygen (by volume);
• D) Oxygen is part of carbon dioxide.

Plan for describing the physical properties of a substance

1. In what state of aggregation - gaseous, liquid or solid - is the substance under these conditions?

2. What color is the substance? Does it have shine?

3. Does the substance have an odor?

4. Does the substance show plasticity, fragility, elasticity?

5. Does the substance dissolve in water?

6. What is the melting point and boiling point of the substance? (See reference books.)

7. What is the density of matter? (See reference books.)

8. Does the substance have thermal and electrical conductivity? (See reference books.)

Exercise #3

Describe the physical properties of acetic acid, sugar, salt, copper, aluminum according to the proposed plan.

(S.10 textbook)

Show the correspondence between the names of substances and their properties.

• Iron
• Oxygen
• Aluminum
• Chlorophyll
• Sugar

• Brilliant
• Colorless
• Transparent
• Light
• red brick
• Sweet
• Green

Choose the right word

A) Glass - flask

Steel - (ore, cast iron, spoon)

B) Aluminum - solid

Mercury - (shiny, silvery white, liquid)

C) Oxygen - odorless

Ammonia - (lighter than air, colorless, has a pungent odor)

D) Battery - cast iron

Vase - (water, glass, substance)

Chemistry and environmental protection

Homework

Paragraph 2

RT s. 4 - 5 (completely),

With. 8 - 9 #10-13

Lesson Objectives:

• educational: form an understanding of the subject of chemistry. To give the initial concepts of matter, a chemical element, about simple and complex substances, about the three forms of the existence of a chemical element.
• Educational: development of logical and semantic thinking of students, memory, chemical language, as well as the ability to carry out independent activities in the classroom.
• nurturing: to cultivate a culture of mental work, to develop the communicative qualities of the individual.

Lesson type: learning a new topic.

Teaching method: partially search, research, problematic.

Organizational forms: conversation, independent work, practical work.

Material support of the lesson: Computer, projector, screen.
On the display table: a collection of glass and aluminum products. Iron filings, sulfur, a magnet, a sheet of white paper and a glass of water.
On student tables: sugar, vegetable oil, sand, aluminum - in test tubes and water in a flask, blanks for designing a laboratory experiment.

Motivation: Knowledge update.

We start with the question “What do you know about chemistry?”
In the course of the conversation, we bring the conversation to the mainstream of the meaning of chemistry,
using stand " Chemistry in our life”.
Chemistry has enormous potential, creates previously unknown materials,
It facilitates the work of a person, clothes, saves time, creates coziness and comfort, and even changes the appearance of people.
But the same chemistry can become hazardous to health, even deadly ...
Science fiction writer and biochemist Isaac Asimov wrote: “Chemistry is death packed in jars and boxes…”
What has been said is sometimes true not only in relation to chemistry, but also in relation to electricity, household appliances, and transport.
We cannot live without electricity, but a bare wire is deadly, we all love to watch TV, but behind its back panel there is a voltage of thousands of volts, we need a car, but people often die under its wheels.
So the use by people of the achievements of modern chemistry requires a high general culture, great responsibility and, of course, knowledge.

Next, we bring students to the idea that a modern person cannot do without what chemistry gives him, and in order not to become like a child who plays with fire and does not understand what he is playing with, a modern person must have at least a general idea of ​​​​the subject of chemistry . Our task today is to find out how this ancient science arose and what is the subject of study of this science?

Study of new material and primary control:

Demonstration of the presentation in the PowerPoint program “The History of Chemistry” (Appendix 1)*.

What does the science of chemistry study? Chemistry is studying: (writing on the board and in a notebook):

• Substances.
• Properties of substances.
• Transformations of substances.

Demonstration collections of products from glass and separately aluminum.
- question: what do all these items have in common (test tubes, flasks, a glass are demonstrated). Answer: they are made of glass;
- question: why can't the same test tube be made of aluminum? What is the difference between glass and aluminum? The answer is properties;

Demonstration: the action of a magnet on iron filings and sulfur,
put iron filings and sulfur in a glass of water.
Frontal discussion of the properties of iron filings and sulfur.

Anchoring: let's perform a laboratory experiment, filling out the result in the proposed blank forms according to the model:

Sample :

Laboratory experience.

Topic: The study of the physical properties of various substances.
Target:________________________________

The result of the work.

1. Add some water to the contents of each of the four test tubes.
2. Describe what happens in the test tube.
3. Of the substances whose properties you have just described, indicate those that:
a) are in the same aggregate state;
b) practically insoluble in water.
4. Compare the properties of sugar and sand, indicate the similarities and differences in the properties of these substances.
CONCLUSION: Various substances can have both _____________ and
And ________________ properties.

Question to the class: What is a physical body? Give examples?
Conclusions: (notebook entry)

1. Matter is what physical bodies are made of.
2. Chemistry is the science of substances, their properties and transformations.

Question: why do you need to know the properties of certain substances? The answer is to use them to your advantage.

The conclusion of this conversation is summarized as follows:

Let's remember what we know from physics:
Substances are made up of molecules, and molecules are made up of
tiny atoms, which in turn
differ as brands of cars: Volga, Muscovite,
Zhiguli, etc. There are about 118 such types of atoms in total.
Thus, the entry in the notebook:

A certain type of atom is called a chemical element.

We explain that each chemical element has
three forms of existence. (transfer the diagram from the board to notebooks)

For instance:

Express fastening:

1. It is suggested that students listen to the statement and raise their right hand if it is a simple substance, and the left hand if it is about an element:
-nitrogen does not support combustion;
- iron has the ability to be magnetized;
- the oxygen content in sulfur(IV) oxide is less than in sulfur(VI) oxide;
- the ammonia molecule consists of nitrogen and hydrogen;
- yellow sulfur;
- iron is a part of many multivitamins.

2. Complete the diagram:

Assimilation control:
Test self-control with self-test - the answers are prepared in advance. (Appendix 2).
Assimilation is judged by the number of correct answers.

1. Any object that surrounds us is:
a) physical body
b) substance

2. Glass vase, glass cup, glass flask is:
a) bodies
b) substances.

3. The substance is:
a) what the physical body consists of;
b) any object around us.

4. Which of the following sentences refers to glass as a physical body?
a) he broke the window pane;
b) the vase is made of glass.

5. The properties of a substance are:
a) features by which substances are similar or different from each other;
b) the color of the substance.

6. Write down what quality adjectives - fragile, short, mirror, fetid, crumbly, symmetrical, porous, curved, silvery, melting - can be attributed:
a) to substances;
b) to bodies;
c) both to bodies and to substances.

7. Choose a simple substance:
a) oxygen
b) water
c) sulfuric acid
d) aluminum oxide

8. Choose a mixture of substances:
a) air
b) magnesium oxide
c) aluminum
d) iron sulfide.

Reflection and summing up:

At the end, share your impressions of the lesson. To do this, complete the sentences dedicated to today.
Today I found out
I was surprised
I would like to______________________________________________

Homework:

When telling the children homework, they should explain the order of its implementation. Which exercises can be performed orally, and which in writing §1., ex. 1 (oral).

Literature:

1. Gabrielyan O.S. Chemistry Grade 8 Textbook for educational institutions Moscow "Business Bustard", 2006
2. Gabrielyan O.S., Voskoboynikova N.P., Yashukova A.V. Handbook of the teacher, 8th grade Moscow "Businessbust", 2002
3. Gorkovenko M.Yu. "Pure lesson development lessons grade 8" Moscow "Vako", 2005
4. Bocharova S.V. “Chemistry grade 8. Lesson plans "Volgograd. "Teacher - Ast", 2004

Internet resources:

• Alchemist.ru - Kunstkamera
• http://a-ivan.by.ru
• http://ru.wikipedia.org/wiki/History_of_chemistry
• http://www.physchem.chimfak.rsu.ru/Source/History/Sketch_2.html