Lesson using the electronic textbook "simple substances - metals". Technological map of a chemistry lesson

Out of 114 chemical elements In the periodic table of D.I. Mendeleev, 92 elements form simple substances with a metal bond in a free state.

Even in ancient times, people paid attention to the special properties of metals: they can be melted and then given any shape, making arrow and spear tips, shields and swords, dishes and plows... In the clock of human history, the Stone Age gave way to the Copper Age , then - bronze, then - iron...

All metals except mercury are in their normal state solids and have a number general properties. Metals are malleable, plastic, viscous substances that have a metallic luster and are thermally and electrically conductive.

In past centuries, metals were credited with many miraculous properties. Known back in Ancient Egypt the seven metals were considered representatives of the seven planets on Earth.

Our ancestors associated gold with the Sun, silver with the Moon, copper with Venus, iron with Mars, tin with Jupiter, lead with Saturn, mercury with Mercury (Fig. 44). The coincidence of the number of metals familiar to the ancients with the number of planets that they saw in the sky would seem to confirm the relationship of earthly metals with celestial bodies. When in the 16th century Alchemists became aware of metallic antimony, but for a long time they refused to recognize it as a metal - after all, there was not enough planet in the sky for antimony.

Rice. 44.
Designation of chemical elements by alchemists

M.V. Lomonosov defined metal “as a light body that can be forged,” and attributed this property to metals: gold, silver, copper, tin, iron and lead. A. Lavoisier in “ Beginner course Chemistry,” written in 1789, already mentioned 17 metals. IN early XIX V. followed by the discovery of platinum metals. To date, the number of known metals has increased to 92.

Plasticity is the most important property of metals to change their shape upon impact, to be rolled into thin sheets and drawn into wire. At the same time, mobile socialized electrons soften the movement of positive ions, shielding them from each other. Therefore, the processing of metals with a change in shape occurs without destruction.

The most ductile of precious metals is gold. One gram of gold can be drawn into a wire two kilometers long.

All metals, as you know, are solid substances under ordinary conditions. The exception, as already noted, is mercury, which under normal conditions is a liquid, shiny silvery-white metal.

Metals vary in hardness. Soft ones are alkaline, for example, or lead, and hard ones are chromium, titanium, molybdenum.

You can get an idea of ​​the melting points and densities of some metals if you carefully examine Figure 45.

Rice. 45.
Melting points and densities of some metals

The presence of socialized electrons also explains such characteristic properties of metals as their thermal and electrical conductivity. Even a small potential difference is enough, and randomly moving electrons begin to move in a strictly ordered manner. The best conductors of electric current are silver, copper, gold, aluminum. In the above list they are arranged in order of decreasing electrical conductivity.

Free electrons also give rise to such properties as metallic luster. Light is absorbed by the surface of the metal, and its electrons begin to emit their own, secondary, waves of radiation, which we perceive as metallic shine. Palladium, mercury, silver, and copper reflect light perfectly.

Laboratory experiment No. 5
Familiarization with the metal collection

Check out the metal collection. Write down the chemical symbols of the metals given to you, arrange them in ascending order:

1. density;
2. plasticity;
3. hardness;
4. metallic shine;
5. electrical conductivity;
6. thermal conductivity.

To complete the task, use Appendices 1 and 2, additional sources of information.

Key words and phrases

Physical properties of metals: malleability, plasticity, ductility, hardness, boiling point, metallic luster, electrical and thermal conductivity.

Work with computer

1. Refer to the electronic application. Study the lesson material and complete the assigned tasks.
2. Find email addresses on the Internet that can serve as additional sources that reveal the content of keywords and phrases in the paragraph. Offer your help to the teacher in preparing a new lesson - send a message by keywords and phrases in the next paragraph.

Questions and tasks

1. Which of the substances named in the poem below is not a metal?

   Seven metals created light
   According to the number of seven planets:
   Copper, iron, silver...
   He gave us the Cosmos for good.
   Gold, tin, lead...
   My son, Sera is their father.
   And you should also know:
   Mercury is their mother to all of them.

2. How to understand the figurative expressions given in this poem: “sulfur is their father” and “mercury is their own mother”?
3. What property of metals is mentioned in the opening line of A. S. Pushkin’s poem “The Dagger”?

   The god of Lemnos has bound you...

   What property of metals is discussed in the lines below?

   Like a hellish ray, like the lightning of the gods,
   A silent blade shines in the villain's eyes,
   And, looking around, he trembles
   Among their feasts...

4. Why are airlines prohibited from transporting devices and equipment containing mercury?
5. Using additional literature, prepare a message about the appearance of mirrors in a person’s life and the improvement of methods for making them.

Taimyr municipal government educational institution"Karaul Secondary Boarding School"

Bugrim Larisa Valerievna, chemistry teacher.

Routing chemistry lesson.

Lesson topic: “Simple substances - metals”

The purpose of the lesson: study the physical properties and applications of simple substances - metals based on their structure.

Planned educational results:

1. Personal: formation of cognitive interest in the study of chemistry; motivating students to gain new knowledge and form a scientific worldview.

Cognitive: establish cause-and-effect relationships, conduct observations.

Regulatory: formulate the purpose of the lesson; work according to plan; draw up a report including a description of the observation, its results, and conclusions.

Communicative: construct speech statements in oral and written form; argue your point of view.

3. Subject : describe the situation elements - metals in the PSHE of D.I. Mendeleev, classify simple substances into metals and non-metals, characterize the general physical properties of metals, establish cause-and-effect relationships between the structure of the atom and chemical bonds in simple substances - metals.

Lesson type: a lesson in learning new knowledge

Means of education: textbook, workbooks, presentation, task cards, metal collections.

Equipment: spoon, mug, paper clip, thermos, school bell, pencil sharpener, glasses of hot water, aluminum and copper wire.

Lesson steps	Teacher activities	Student activities
1) Organizational stage.	Greets students and determines readiness for class	Teachers greet and check their jobs.	Communicative: learn the culture of communication.
2) Setting the goals and objectives of the lesson. Motivation educational activities students.	Teacher: each group has a task on their desks. You need to complete them and determine the topic of our lesson. The teacher organizes work to formulate the goals of educational activities, to master generalized methods of acquiring new knowledge	They work in groups, complete tasks and determine the topic of the lesson. Group 1: examines objects, determines what is common: all objects are made of metals. Group 2: solves puzzles Group 3: determines chemical elements using an electronic formula. Determine the topic of the lesson: “Metals.” They answer questions and express their assumptions. They formulate the specific goal of their future educational actions, eliminating the cause of the difficulty that has arisen (i.e., they formulate what knowledge they need and what they need to learn). They propose and agree with the teacher the topic (main question) of the lesson. Realize the purpose of the upcoming activity.	Personal: personal self-determination. Communicative: learn to express their thoughts, culture of communication. Cognitive: learn to construct statements; learn to analyze, compare
3) Updating knowledge.	Teacher: let’s remember what we already know about metals by completing the “True-False” task. The teacher organizes the work to complete the task on cards.	Complete the task on cards, using their answers, fill in the gaps in the text. Carry out mutual verification	Regulatory: control, assessment, correction. Cognitive: general educational – the ability to structure knowledge, choosing the most effective ways solving a task, the ability to consciously and voluntarily build speech utterance. Communicative: creating a written response – control, correction
4) Primary assimilation of new knowledge.	1. Invites the group to work with the collection of metals according to the instructional map and answer the questions: do we meet in Everyday life these metals; what is their position in the PSHE, is it possible to draw a parallel between the structure of metal atoms and the peculiarities of their physical properties. 2. Organizes independent work with textbook, filling out table	1. In a group (3-4 people) they work with metal collections, perform laboratory work, and answer questions. They observe, analyze, and draw conclusions about the physical properties of metals. 2. Work individually with the textbook (semantic reading), highlight the main thing, write it down in a notebook (fill out the table). 3. Together with the teacher, answer questions and make a generalization.	Cognitive: they learn to navigate the textbook, find and use the necessary information (semantic reading), learn to construct statements; learn to analyze, compare, generalize, and establish cause-and-effect relationships. Communicative: they learn to listen and understand the speech of another person, learn to independently organize educational interaction when working in pairs, and develop the ability to express their thoughts. Regulatory: learn to exercise self-control and correction; Personal: formation of life self-determination.
5) Initial check of understanding
6) Primary consolidation.	Organizes the work of filling out the text in workbook;self-test.	Fill in the text with the missing words in the workbook and carry out a self-test.	Cognitive: learn to construct statements; analyze, compare, generalize, establish cause-and-effect relationships. Communicative: learn to listen and understand another person’s speech, develop the ability to express their thoughts. Regulatory: learn to exercise self-control and correction
7) Information about homework, instructions on how to complete it	tasks on pp. 53-55 for a choice of 3-5 tasks. Creative task: make puzzles, riddles, crosswords or cinquains on the topic	Write down homework, ask questions, comprehend assignments
8) Reflection (summarizing the lesson)	The teacher organizes students’ self-assessment of their own learning activities in the lesson, the measure of their progress towards the goal. Select 1-2 sentences and complete them in your notebook: today I found out... it was difficult… I realized that... I learned… It was interesting to know that... I was surprised...	Determine the degree of compliance with the set goal and performance results. Determine the degree of their progress towards the goal, express value judgments. Formulate and write down what they learned in class.	Cognitive: learn to navigate a workbook, find and use the necessary information, learn to construct statements; learn to analyze, compare, generalize, and establish cause-and-effect relationships. Communicative: learn to listen and understand another person’s speech, learn to express their thoughts. Regulatory: learn to exercise self-control and correction. Personal: formation of personal self-determination.

Work in groups.

1 group.

Exercise: You have objects on your desktop: a spoon, a mug, a paper clip, a thermos, a school bell, a pencil sharpener. Determine what all these items have in common.

2nd group.

Exercise: solve puzzles. How, in one word, can these elements be called?

3rd group.

Exercise: Use the electronic formula to determine the chemical elements. How can one describe them in one word?

b) 1s 2 2s 2 2p 6 3s 1

c) 1s 2 2s 2 2p 6 3s 2

d) 1s 2 2s 2 2p 6 3s 2 3p 6 4s 1

Exercise. "True False"

Statement			"Don't know"
1.Metal atoms have big number electrons on the outer layer (from 4 to 8)
2.Metal atoms have a small number of electrons in the outer layer (from 1 to 3)
3. The radius of a metal atom is greater than the radius of a non-metal atom
4. The radius of a metal atom is less than the radius of a non-metal atom
5.Metal atoms tend to accept missing electrons before completing the level
6. Metal atoms tend to give up outer electrons
7. Metal atoms, when they donate electrons, turn into cations
8. Metal atoms, when accepting electrons, turn into anions
9.Metal ions cause two types of chemical bonds: metallic and covalent
10. Metal ions cause two types of chemical bonds: ionic and metallic

Using your correct answers, fill out the text on the topic “Metals” - task No. 2-3 p. 52 in the workbook.

Laboratory work “Physical properties of metals”.

Target: get acquainted with the physical properties of metals

Equipment: a collection of metals (or a set of metals: aluminum wire, copper wire), glasses with hot water.

Safety regulations:

Exercise: check out the metal collection. Write down the chemical symbols of the metals given to you, study the physical properties. Enter the results in the table.

1. Examine the samples and determine in what state of aggregation the given metals are.

2.Look at samples of metals and determine their color.

3.Look at samples of metals and determine whether they have shine.

4. Bend the metal wire several times and determine whether they are ductile.

5.Dip the wire into a glass of hot water and determine whether the metals conduct heat.

6.Remember from life experience, physics course, do metals conduct? electricity.

7.Draw a conclusion.

	State of aggregation			Plastic	Thermal conductivity	Electrical conductivity

Conclusion: metals have general physical properties:

Fill out the table using the textbook materials on p.

Physical property	What is the reason	Examples of metals in which this property is most pronounced

Part I

1. Position of metals (M) in Periodic table D. I. Mendeleev.

Conditional diagonal from B to At through elements of A groups: IV→ V→ VI.OndiagonalsAndaboveherlocatednonmetals, Aunderher- metals.
OnlyfromMconsistINgroups. Totalfrom 110 elementsTometalsinclude 88 elements.
I.A.group- Thisalkalinemetals.
IIAgroup- Thisalkaline earthmetals.

2. Features of the structure of M atoms:

1) the number e in the outer layer of the atom is 1-3;
2) R atom - large size.

3. The relativity of dividing elements into M and NM (give examples):

1) gray tin - NM, white tin - M.
2) graphite is NM, but electrically conductive.
3) Cr, Zn, Al - M, but amphoteric.

4. Metal chemical bond- This connection in metals and alloys between atom-ions through socialized e.

General scheme for the formation of a metallic bond:

5. Fill out the table “Structure and properties of metals.”

6. Write down the signs by which you can distinguish plates made:

a) from aluminum and copper - color, density, electrical and thermal conductivity
b) from lead and aluminum - color, density, melting point
c) from silver and graphite - color, shape, electrical conductivity.

7. Using the pictures, fill in the blanks to create a sequence: name of metal(s), properties(s), area(s) of application.

a) cast iron battery - cast iron, thermal conductivity, strength, wear resistance. In the economy, everyday life, metallurgy.
b) aluminum foil - aluminum, easy to roll out, plasticity, high electrical and thermal conductivity, corrosion resistance. IN Food Industry, production of alloys.
c) steel buttons and paper clips - steel, “soft” steel, elastic, easy to bend, does not rust, strong and hard. In all sectors of the national economy.
d) metal support - iron (steel), durable, solid, not exposed to the environment. In all sectors of the national economy.
e) domes - gold, inert, appearance. Used in construction - rolling, in jewelry.
f) thermometer - mercury (liquid metal), expands when heated, in medical thermometers. Obtaining alloys for gold mining. Lamps.

8. Fill out the “Classification of Metals” table.

9. Alloy is is a homogeneous metallic material consisting of a mixture of two or more chemical elements with a predominance of metal components.

10. Ferrous alloys:

1) cast iron, carbon content >2%
2) steel, carbon content<2%.

11. Fill out the table “Alloys and their components.”

12. Write the names of the alloys from which the objects shown in the pictures can be made.

a) steel
b) cupronickel
c) duralumin
d) bronze
e) bronze
e) cast iron

Part II

1. Metal atoms having in the outer layer:

a) 5e - Sb (antimony), Bi (bismuth)
b) 6e - Po (polonium)

Why?
They are located in 5 and 6 groups respectively

2. Metal atom having 3e in the outer layer , - boron.
Why?
It is located in group 3.

3. Fill out the table “Atomic structure and chemical bonding.”

4. Eliminate the “extra element.”
4) Si

5. Which of the following groups of elements contains only metals?
There is no right answer

6. What physical property is not common to all metals?
3) solid state of aggregation under standard conditions

7. Which statement is true?
4) metal atoms and metals - simple substances exhibit only reducing properties.

8. All elements of the main subgroups are metals if they are located in the Periodic Table below the diagonal:
3) boron - astatine

9. The number of electrons in the outer electronic level of a metal atom located in the main subgroup of the Periodic Table cannot be equal to:
4) 7

Summary of a chemistry lesson on the topic "Metallic bond" 8th grade

teacher of chemistry and biology MBOU KSOSH

Babeshko E.V.

Lesson type: Learning new material.

Type of lesson: Combined lesson.

The purpose of the lesson: Form ideas about metal bonding.

Lesson objectives:

1) find out how atoms of metal elements interact with each other; find out how a metal bond affects the properties of the substances formed by it; generalize knowledge about chemical bonds.

2) formation of a scientific worldview.

3) developing interest in the subject through playful moments.

Equipment:

Computer, projector, presentation.

Organizing time.

2.Updating knowledge, checking homework.

In previous lessons, you learned how atoms of metal elements and non-metal elements interact with each other, as well as atoms of non-metal elements with each other. I hope you have a good understanding of these topics and can answer the following questions without difficulty.

Questions:

What types of chemical bonds do you already know?

What is an ionic bond?

What is a covalent bond?

What types of covalent bonds do you know? How can you tell them apart?

Now let's do the following exercises.

Exercise 1

Write down the schemes for the formation of ionic bonds in the following substances:

a) CaS

b) MgCl2

c) Na3N

Exercise 2

Write down the schemes for the formation of covalent bonds in the following substances:

a) N2

b) CH4

c) HF

3. Learning new material:

Today we will get acquainted with how atoms of metal elements interact with each other.

Therefore, what is the topic of today's lesson? (students name the topic of the lesson). Metal chemical bond.

Metals usually do not exist as isolated atoms, but in the form of a piece, ingot, or metal product. Let's find out what holds the metal atoms in a single volume.

The atoms of most metals at the outer level contain a small number of electrons - 1,2,3. These electrons are easily stripped off and the metal atoms become ions.

Meh 0 –nē⇆ Me + n + atoms-metal ions

The detached electrons move from one ion to another, binding them into a single whole. It is impossible to figure out which electron belongs to which atom. Therefore, all the detached electrons become common.

Electrons can combine with cations, then atoms are temporarily formed, from which electrons are again stripped. This process continues endlessly. Thus, in the volume of the metal, atoms are continuously converted into ions and vice versa.

The detached electrons move freely from one ion to another as atoms approach each other. In this case, a small number of shared electrons binds a large number of metal atoms and ions. Since the number of electrons in a metal is equal to the total charge of the positive ions, the metal as a whole remains electrically neutral.

You can imagine that metal ions are in a cloud of electrons. Such an electron cloud is called an “electron gas.”

Let's write down the definition: The bond in metals between atoms and ions, formed due to the sharing of electrons, is called metallic.

Now let's think about what type of bond a metal bond is like.

Student answers:

✓ Ionic bond (cations are formed and Me ions are bonded due to electrostatic attraction).

✓ The covalent bond is based on the socialization of ē. Only in a covalent bond do the electrons of neighboring atoms unite, while in a metallic bond do electrons belong to all atoms.

Metallic bonding is characteristic of both pure metals and mixtures of various metals - alloys in solid and liquid states.

Metal pairs consist of individual molecules (monatomic and diatomic). Metal atoms are linked together by covalent bonds.

For example:

Na. + .Na → Na:Na → Na – Na

The metallic bond determines the basic properties of metals

- electrical conductivity and thermal conductivity

Electrons move randomly throughout the metal. But even a small potential difference is enough for the electrons to begin to move in an orderly manner. The best current conductors are Ag, Cu, Au, Al.

- plasticity

Electrons soften the movement of ions under external influence. The most ductile are Au, Ag, Cu.

- metallic shine

The light is absorbed by the metal and the electrons begin to emit their own waves of radiation. Ag, Cu, Al, Pd, Hg reflect light better than others.

Metals vary in hardness . Soft ones are alkaline, for example, or lead, and hard ones are chromium, titanium, molybdenum.

Picture ofmelting points and density You can get some metals if you look carefully at Figure 45 on page 83.

4. Reflection.

1.Laboratory experience .

Familiarization with the collection of metals.

Check out the metal collection. Write down the chemical symbols of the metals given to you, arrange them in ascending order:

1) density;

2) plasticity;

3) hardness;

4) metallic luster;

5) electrical conductivity;

6) thermal conductivity.

To complete the task, use appendices 1 and 2 of the textbook, additional sources of information.

2.Now let’s fill out the general table “Types of chemical bonds”

Between what atoms does it occur?

Difference in EO of 2 neighboring atoms

Examples

covalent

polar

neMe(1) + neMe(2)

< 1,7

H 2 O

non-polar

neMe(1) + neMe(1)

Cl 2

ionic

Me + neMe

> 1,7

CaCl 2

metal

Me + Me

Perform the following exercise.

Exercise

Find the odd one out:

A)CuCl 2 , Al, MgS

b) N 2 , HCl, O 2 V) Ca, CO 2 , FeG) MgCl 2 , N.H. 3 , H 2

Answer:

A)CuCl 2 , Al , MgS

b)N 2 , HCl , O 2

V)Ca,CO 2 , Fe

G) MgCl 2 , N.H. 3 , H 2

First, students do the exercises in their notebooks on their own., individual students comment on the exercises,and thenThe correct answers to these questions are projected on the screen.

Checking this work will show the quality of assimilation of the studied material, will allow you to correct moments of misunderstanding in the next lesson, and provide differentiated assistance to students.

5. Homework

§13,

Exercises 1-4.