Summary of a lesson in chemistry in 9th grade On the topic: “Alloys”

Chemistry lesson in 9th grade “Obtaining metals”

Author, developer:

Teacher Talitskikh M.V. MBOU Secondary School St. Lukovskaya named after S.G. Astanin, Mozdok district, North Ossetia-Alania

Item:

Chemistry

(the work program is compiled on the basis of the Federal State Educational Standard, the author’s chemistry program by O.S. Gabrielyan and is focused on the use of the textbook “Chemistry. 9th grade” by O.S. Gabrielyan - M.: Bustard, 2013)

Class:

9th grade

Lesson type:

For the leading didactic purpose:

lesson on learning new material;

By way of organizing activities:

individual-group;

According to the leading teaching method:

problem-search.

Lesson duration:

1 lesson of 40 minutes.

Technology

: developmental education, critical thinking technology, problem-based learning, collaborative learning, ICT, health-saving technologies.

Lesson objectives.

Educational:

To introduce students to natural compounds of metals and native metals;

Give the concept of ores and metallurgy;

Consider its varieties such as pyro-, hydro- and electrometallurgy, metallothermy.

Educational:

Strengthen the ability to find oxidation states;

Development of students’ cognitive activity, developing the ability to observe, analyze, draw conclusions, explain the course of the experiment;

Formation of basic educational competencies: educational, communicative, personal;

Develop the ability to think outside the box, creatively;

Educational:

Develop communication skills, the ability to express one’s own opinion, and cooperate in pairs;

Orienting students towards a healthy lifestyle;

Formation of correct self-esteem of students;

Fostering the need for knowledge, increasing cognitive interests, instilling interest in chemistry.

Health-saving technologies:

monitor students’ posture; carry out exercises to relieve eye strain; ventilation of the room.

Methods - see Appendix

Main: problem-search

Means of education:

1) textbook “Chemistry. 9th grade” Gabrielyan O.S. – M.: Bustard, 2013.

2) multimedia projector, screen, computer, speakers, videos (“Unified Collection of Digital Educational Resources”), table of chemical elements.

3) on the students’ desks there is a notebook in which students take notes throughout the lesson.

4) chemical reagents for laboratory experiments.

Formation of UUD - see in the Appendix:

Subject:

P 1:

Know the characteristic properties of amphoteric elements and their compounds;

P 2:

Have an idea of solving new types of problems;

P 3:

analysis and synthesis of information;

Student activities - see Appendix

During the classes

(see technological map).

Subject:

“General methods of obtaining metals” 9th grade.

The purpose of the lesson:

introduce natural compounds of metals and native metals; give the concept of ores and metallurgy, consider such varieties as pyro-, hydro-, electrometallurgy, thermal decomposition of metal compounds, demonstrate laboratory methods for producing metals and, using fragments of the media lecture, introduce the industrial production of metals.

Equipment:

computer, video projector,

I. Organizational moment. Greeting

II. Checking homework.

1. Write equations for reactions of interaction between substances:

a) Li, Na, Ca, Fe with O2, Cl2, S, N2, C:

b) Na, Ca, Al with H2O;

c) Zn with H2SO4; Al with HCl;

d) Zn with CuSO4; Al with NaOH; Be with KOH.

2. Carry out the following. reactions: Al Al(OH)3 _ Al2 O3 AlCl3  Al(OH)3

Mg  MgO  MgSO4  Mg(OH)2

III.
Natural metal compounds.
Metals occur in nature in three forms:

1) gold and platinum are found in free form; gold occurs in a dispersed state, and sometimes collects in large masses? nuggets. So in Australia in 1869 they found a block of gold weighing one hundred kilograms. Three years later, they discovered an even larger block weighing about two hundred and fifty kilograms. Our Russian nuggets are much smaller, and the most famous one, found in 1837 in the Southern Urals, weighed only about thirty-six kilograms. In the middle of the 17th century in Colombia, the Spaniards, panning for gold, found heavy silver metal along with it. This metal seemed as heavy as gold, and it could not be separated from gold by washing. Although it resembled silver (plata in Spanish), it was almost insoluble and stubbornly resisted smelting; it was considered an accidental harmful impurity or a deliberate counterfeit of precious gold. Therefore, the Spanish government ordered at the beginning of the 18th century to throw this harmful metal back into the river in front of witnesses. Platinum deposits are also located in the Urals. It is a massif of dunite (igneous rock consisting of iron and magnesium silicates with an admixture of iron ore). It contains inclusions of native platinum in the form of grains.

2) silver, copper, mercury and tin can be found in nature in native form and in the form of compounds;

3) all metals that are located before tin in the voltage series are found only in the form of compounds.

Most often, metals are found in nature in the form of salts of inorganic acids: chlorides? sylvinite KCl • NaCl, rock salt NaCl;

nitrates – Chilean saltpeter NaNO3;

sulfates – Glauber's salt Na2SO4 ? 10 H2O, gypsum CaSO4 • 2H2O;

carbonates – chalk, marble, limestone CaCO3, magnesite MgCO3, dolomite CaCO3 • MgCO3;

sulfides? sulfur pyrite FeS2, cinnabar HgS, zinc blende ZnS;

phosphates – phosphorites, apatites Ca 3(PO4)2;

oxides – magnetic iron ore Fe3O4, red iron ore Fe2O3, brown iron ore containing various iron (III) hydroxides

Fe2O3 • H2O.

Back in the middle of the 2nd millennium BC. e. In Egypt, the production of iron from iron ores was mastered. This marked the beginning of the Iron Age in human history, which replaced the Stone and Bronze Ages. On the territory of our country, the beginning of the Iron Age dates back to the turn of the 2nd and 1st millennia BC. e.

Minerals and rocks containing metals and their compounds and suitable for the industrial production of metals are called ores.

The industry that deals with the extraction of metals from ores is called metallurgy. The same name is given to the science of industrial methods for obtaining metals from ores.

III. Obtaining metals.

— What is the main chemical process that underlies the production of metals?

Most metals are found in nature as part of compounds in which the metals are in a positive oxidation state, which means that in order to obtain them in the form of a simple substance, it is necessary to carry out a reduction process.

But before restoring a natural metal compound, it is necessary to convert it into a form that can be processed, for example, the oxide form, followed by the reduction of the metal. The pyrometallurgical method is based on this

. This is the reduction of metals from their ores at high temperatures using non-metallic reducing agents? coke, carbon monoxide (II), hydrogen; metal? aluminum, magnesium, calcium and other metals. .

Pyrometallurgical method:

Obtaining copper from oxide using hydrogen.

Cu +2O + H2 = Cu0 + H2O (hydrothermy)

Preparation of iron from oxide using aluminum.

Fe+32O3 +2Al = 2Fe0 + Al2O3 (aluminothermy)

To obtain iron in industry, iron ore is subjected to magnetic enrichment: 3Fe2 O3 + H2 = 2Fe3 O4 + H2O or 3Fe2O3 + CO = 2Fe3O4 + CO2, and then the reduction process takes place in a vertical furnace:

Fe3O4 + 4H2 = 3Fe + 4H2O

Fe3O4 + 4CO = 3Fe + 4CO2

View media lecture. (CD)

Hydrometallurgical method

is based on the dissolution of a natural compound in order to obtain a solution of a salt of this metal and the displacement of this metal by a more active one. For example, the ore contains copper oxide and is dissolved in sulfuric acid:

CuO + H2SO4 = CuSO4 + H2O, then carry out a substitution reaction

CuSO4 + Fe = FeSO4 + Cu.

Electrometallurgical method.

These are methods of producing metals using electric current (electrolysis). View a fragment of the media lecture. (CD)

This method produces aluminum, alkali metals, and alkaline earth metals. In this case, melts of oxides, hydroxides or chlorides are subjected to electrolysis:

NaCl -> Na+ + Cl?

cathode Na+ + e > Na0 ¦ 2

anode 2Cl? ?2e > Cl20 ¦ 1

overall equation: 2NaCl = 2Na + Cl2

A modern, cost-effective method for producing aluminum was invented by the American Hall and the Frenchman Héroult in 1886. It involves electrolysis of a solution of aluminum oxide in molten cryolite. Molten cryolite dissolves Al2O3, just as water dissolves sugar. Electrolysis of a “solution” of aluminum oxide in molten cryolite occurs as if the cryolite was only a solvent, and aluminum oxide? electrolyte.

Al2O3 —> AlAlO3 —> Al3+ + AlO33–

cathode Al3+ +3e —> Al 0 ¦ 4

anode 4AlO33– – 12 e —> 2Al2O3 +3O2 ¦ 1

overall equation: 2Al2O3= 4Al + 3O2.

In the English “Encyclopedia for Boys and Girls,” an article on aluminum begins with the following words: “On February 23, 1886, a new metal age began in the history of civilization - the age of aluminum. On this day, Charles Hall, a 22-year-old chemist, walked into his first teacher's laboratory with a dozen small balls of silvery-white aluminum in his hand and with the news that he had found a way to make the metal cheaply and in large quantities." So Hall became the founder of the American aluminum industry and an Anglo-Saxon national hero, as a man who turned science into a great business.

Thermal decomposition of compounds.

Iron reacts with carbon monoxide (II) at elevated pressure and temperature 100-2000, forming pentacarbonyl: Fe + 5CO = Fe (CO)5

Iron pentacarbonyl is a liquid that can be easily separated from impurities by distillation. At a temperature of about 2500, carbonyl decomposes, forming iron powder: Fe (CO)5 = Fe + 5CO.

If the resulting powder is sintered in a vacuum or in a hydrogen atmosphere, the result is a metal containing 99.98–99.999% iron. An even deeper degree of iron purification (up to 99.9999%) can be achieved using the zone melting method.

Thus, we became acquainted with natural compounds of metals and methods for isolating metal from them as a simple substance.

IV. Securing the topic.

Complete test tasks:

1. Indicate the following true statements: a) all elements of the d- and f-families are metals; b) there are no metals among the elements of the p-family; c) metal hydroxides can have both basic, amphoteric and acidic properties; d) metals cannot form hydroxides with acidic properties.

2. In which row are the symbols of the hardest and most refractory metals, respectively?

a) W, Ti; b) Cr, Hg; c) Cr, W; d) W, Cr,

3. Indicate the symbols of metals that can be oxidized by H+ ions in an aqueous acid solution: a) Cu; b) Zn; c) Fe; d) Ag.

4. Which metals cannot be obtained in sufficiently pure form by reducing their oxides with coke? a) W; b) Cr; c) Na; d) Al.

5. The following react with water only when heated: a) sodium; b) zinc; c) copper; d) iron.

6. Which statements are incorrect for metals: a) metals make up the majority of the elements of the Periodic Table; b) the atoms of all metals at the outer energy level contain no more than two electrons; c) in chemical reactions, metals are characterized by reducing properties; d) in each period the alkali metal atom has the smallest radius.

7. Mark the formula of the metal oxide with the most pronounced acidic properties:

a) K2O; b) MnO; c) Cr2O3; d) Mn2O7.

8. In which pairs do both of the reactions, the schemes of which are given below, allow one to obtain a metal?

a) CuO + CO—> and CuSO4 + Zn —> b) AgNO3 —> and Cr2O3 + Al c) ZnS + O2 and Fe2O3 + H2 —> d) KNO3 —> and ZnO + C.

9. Which metal atoms contain five electrons in the ground state at the energy d-sublevel?

a) titanium; b) chromium; c) antimony; d) manganese.

10. What minimum volume (no.) of carbon (II) monoxide is needed to reduce 320 g of iron (III) oxide to magnetite? a) 14.93 l; b) 15.48 l; c) 20.12 l; d) 11.78 l.

V. D/Z repeat

2. In which row are the symbols of the hardest and most refractory metals, respectively?

a) W, Ti; b) Cr, Hg; c) Cr, W; d) W, Cr,

3. Indicate the symbols of metals that can be oxidized by H+ ions in an aqueous acid solution: a) Cu; b) Zn; c) Fe; d) Ag.

4. Which metals cannot be obtained in sufficiently pure form by reducing their oxides with coke? a) W; b) Cr; c) Na; d) Al.

5. The following react with water only when heated: a) sodium; b) zinc; c) copper; d) iron.

7. Mark the formula of the metal oxide with the most pronounced acidic properties:

a) K2O; b) MnO; c) Cr2O3; d) Mn2O7.

8. In which pairs do both of the reactions, the schemes of which are given below, allow one to obtain a metal?

a) CuO + CO—> and CuSO4 + Zn —> b) AgNO3 —> and Cr2O3 + Al c) ZnS + O2 and Fe2O3 + H2 —> d) KNO3 —> and ZnO + C.

9. Which metal atoms contain five electrons in the ground state at the energy d-sublevel?

a) titanium; b) chromium; c) antimony; d) manganese.

10. What minimum volume (no.) of carbon (II) monoxide is needed to reduce 320 g of iron (III) oxide to magnetite? a) 14.93 l; b) 15.48 l; c) 20.12 l; d) 11.78 l.

2. In which row are the symbols of the hardest and most refractory metals, respectively?

a) W, Ti; b) Cr, Hg; c) Cr, W; d) W, Cr,

3. Indicate the symbols of metals that can be oxidized by H+ ions in an aqueous acid solution: a) Cu; b) Zn; c) Fe; d) Ag.

4. Which metals cannot be obtained in sufficiently pure form by reducing their oxides with coke? a) W; b) Cr; c) Na; d) Al.

5. The following react with water only when heated: a) sodium; b) zinc; c) copper; d) iron.

7. Mark the formula of the metal oxide with the most pronounced acidic properties:

a) K2O; b) MnO; c) Cr2O3; d) Mn2O7.

8. In which pairs do both of the reactions, the schemes of which are given below, allow one to obtain a metal?

a) CuO + CO—> and CuSO4 + Zn —> b) AgNO3 —> and Cr2O3 + Al c) ZnS + O2 and Fe2O3 + H2 —> d) KNO3 —> and ZnO + C.

9. Which metal atoms contain five electrons in the ground state at the energy d-sublevel?

a) titanium; b) chromium; c) antimony; d) manganese.

10. What minimum volume (no.) of carbon (II) monoxide is needed to reduce 320 g of iron (III) oxide to magnetite? a) 14.93 l; b) 15.48 l; c) 20.12 l; d) 11.78 l.

2. In which row are the symbols of the hardest and most refractory metals, respectively?

a) W, Ti; b) Cr, Hg; c) Cr, W; d) W, Cr,

3. Indicate the symbols of metals that can be oxidized by H+ ions in an aqueous acid solution: a) Cu; b) Zn; c) Fe; d) Ag.

4. Which metals cannot be obtained in sufficiently pure form by reducing their oxides with coke? a) W; b) Cr; c) Na; d) Al.

5. The following react with water only when heated: a) sodium; b) zinc; c) copper; d) iron.

7. Mark the formula of the metal oxide with the most pronounced acidic properties:

a) K2O; b) MnO; c) Cr2O3; d) Mn2O7.

8. In which pairs do both of the reactions, the schemes of which are given below, allow one to obtain a metal?

a) CuO + CO—> and CuSO4 + Zn —> b) AgNO3 —> and Cr2O3 + Al c) ZnS + O2 and Fe2O3 + H2 —> d) KNO3 —> and ZnO + C.

9. Which metal atoms contain five electrons in the ground state at the energy d-sublevel?

a) titanium; b) chromium; c) antimony; d) manganese.

10. What minimum volume (no.) of carbon (II) monoxide is needed to reduce 320 g of iron (III) oxide to magnetite? a) 14.93 l; b) 15.48 l; c) 20.12 l; d) 11.78 l.

2. In which row are the symbols of the hardest and most refractory metals, respectively?

a) W, Ti; b) Cr, Hg; c) Cr, W; d) W, Cr,

3. Indicate the symbols of metals that can be oxidized by H+ ions in an aqueous acid solution: a) Cu; b) Zn; c) Fe; d) Ag.

4. Which metals cannot be obtained in sufficiently pure form by reducing their oxides with coke? a) W; b) Cr; c) Na; d) Al.

5. The following react with water only when heated: a) sodium; b) zinc; c) copper; d) iron.

7. Mark the formula of the metal oxide with the most pronounced acidic properties:

a) K2O; b) MnO; c) Cr2O3; d) Mn2O7.

8. In which pairs do both of the reactions, the schemes of which are given below, allow one to obtain a metal?

a) CuO + CO—> and CuSO4 + Zn —> b) AgNO3 —> and Cr2O3 + Al c) ZnS + O2 and Fe2O3 + H2 —> d) KNO3 —> and ZnO + C.

9. Which metal atoms contain five electrons in the ground state at the energy d-sublevel?

a) titanium; b) chromium; c) antimony; d) manganese.

10. What minimum volume (no.) of carbon (II) monoxide is needed to reduce 320 g of iron (III) oxide to magnetite? a) 14.93 l; b) 15.48 l; c) 20.12 l; d) 11.78 l.

2. In which row are the symbols of the hardest and most refractory metals, respectively?

a) W, Ti; b) Cr, Hg; c) Cr, W; d) W, Cr,

3. Indicate the symbols of metals that can be oxidized by H+ ions in an aqueous acid solution: a) Cu; b) Zn; c) Fe; d) Ag.

4. Which metals cannot be obtained in sufficiently pure form by reducing their oxides with coke? a) W; b) Cr; c) Na; d) Al.

5. The following react with water only when heated: a) sodium; b) zinc; c) copper; d) iron.

7. Mark the formula of the metal oxide with the most pronounced acidic properties:

a) K2O; b) MnO; c) Cr2O3; d) Mn2O7.

8. In which pairs do both of the reactions, the schemes of which are given below, allow one to obtain a metal?

a) CuO + CO—> and CuSO4 + Zn —> b) AgNO3 —> and Cr2O3 + Al c) ZnS + O2 and Fe2O3 + H2 —> d) KNO3 —> and ZnO + C.

9. Which metal atoms contain five electrons in the ground state at the energy d-sublevel?

a) titanium; b) chromium; c) antimony; d) manganese.

10. What minimum volume (no.) of carbon (II) monoxide is needed to reduce 320 g of iron (III) oxide to magnetite? a) 14.93 l; b) 15.48 l; c) 20.12 l; d) 11.78 l.

2. In which row are the symbols of the hardest and most refractory metals, respectively?

a) W, Ti; b) Cr, Hg; c) Cr, W; d) W, Cr,

3. Indicate the symbols of metals that can be oxidized by H+ ions in an aqueous acid solution: a) Cu; b) Zn; c) Fe; d) Ag.

4. Which metals cannot be obtained in sufficiently pure form by reducing their oxides with coke? a) W; b) Cr; c) Na; d) Al.

5. The following react with water only when heated: a) sodium; b) zinc; c) copper; d) iron.

7. Mark the formula of the metal oxide with the most pronounced acidic properties:

a) K2O; b) MnO; c) Cr2O3; d) Mn2O7.

8. In which pairs do both of the reactions, the schemes of which are given below, allow one to obtain a metal?

a) CuO + CO—> and CuSO4 + Zn —> b) AgNO3 —> and Cr2O3 + Al c) ZnS + O2 and Fe2O3 + H2 —> d) KNO3 —> and ZnO + C.

9. Which metal atoms contain five electrons in the ground state at the energy d-sublevel?

a) titanium; b) chromium; c) antimony; d) manganese.

10. What minimum volume (no.) of carbon (II) monoxide is needed to reduce 320 g of iron (III) oxide to magnetite? a) 14.93 l; b) 15.48 l; c) 20.12 l; d) 11.78 l.

Obtaining metals. Finding them in nature

Obtaining metals. Finding them in nature

Guys, today we will visit the places where metals are obtained, and we will also find out where metals are found.

Well, let's begin the journey. Metals occur in nature in a free state, they are called native metals

, and
in the form of connections.
In a native state

Gold, silver, copper, platinum and mercury
are found in nature .
These metals are usually found in small quantities as grains or inclusions in rocks. Occasionally there are also quite large pieces of metal - nuggets
.
One of the largest deposits of pure silver was the so-called " silver pavement
" in
Canada
. It was a block of almost pure silver thirty meters long, going eighteen meters into the ground. The mining of this deposit yielded about twenty tons of metal. And one of the largest silver nuggets weighed almost one hundred and nine kg. The largest nugget of copper weighed four hundred and twenty tons, and gold - one hundred and twelve kg.

But the prevalence of metal chemical elements in the earth’s crust varies. To the most common metals

include aluminum (7.45%), iron (4.20%), calcium (3.25%), sodium (2.40%), potassium (2.35%) and magnesium (2.35%). The content of other metals in the earth's crust can be thousandths of a percent or lower.

Some historians believe that the decline of the Roman Empire

was caused by massive lead poisoning.
It is known that the water pipes of Ancient Rome
were made of
lead
.
Water and wine were stored in lead vats. Once in the human body, lead causes damage to the central nervous system and leads to changes in blood composition
.

Many metals are elements necessary for the functioning of living organisms

. Na+, K+, Mg2+, Ca2+ ions account for 99% of all metal ions in the human body.

The
biologically most significant metals include:
K , Na , Mg , Ca , Fe , Cu , Co , Mn , Zn , Mo.

In the earth's crust, metals are most often found in the form of compounds: such as oxides, silicates, carbonates, sulfides and chlorides

.
These compounds are found in ores and minerals
.

Ore is a rock from which it is economically profitable to obtain pure metal.

.
The ore contains minerals and impurities in the form of waste rock. And minerals are natural bodies that have a certain chemical composition
. Let's look at the names and chemical composition of some minerals.

Name	Chemical composition
Red iron ore (hematite)	Fe2O3
Magnetic iron ore (magnetite)	Fe3O4
Brown iron ore	2Fe2O3 3H2O
Iron pyrite (pyrite)	FeS2
Silvin	KCl
Cryolite	Na3AlF6
Calcite	CaCO3
Corundum	Al2O3
Malachite	(CuOH)2CO3
Copper pyrite (chalcopyrite)	CuFeS2
Cinnabar	HgS
Gypsum	CaSO4 2H2
Lead shine (galena)	PbS
Zinc blende	ZnS

The most famous minerals include pyrite, or iron pyrite.

(FeS2),
cinnabar
(HgS),
malachite
((CuOH)2CO3). Pyrite and cinnabar are used in industry to obtain the corresponding metals, that is, iron and mercury, and malachite is used as an ornamental stone.

Now imagine that at the bottom of reservoirs there are also metal compounds, these deposits - nodules - are clusters, tubers or cakes

, densely dotting the bottom.
Flat lake and swamp nodules the size of a small coin were known back in the Middle Ages, which is why they were called “ penny ore
.”
Currently, ferromanganese nodules covering vast areas on the ocean floor are called minerals the 21st century
. It is the richest source of not only iron and manganese, but also cobalt, nickel, copper and molybdenum.

Imagine yourself as a geologist

or
mineralogy
, how exciting it is.
To do this, compare minerals such as red, brown and magnetic iron ore
.

color brownish red

, it itself is
strong, dense
, and if you run a sample of ore across the surface of a porcelain mortar, it leaves a red-brown mark and is not attracted by a magnet.

Brown iron has a yellow-brown color

, itself
durable and dense, not attracted by a magnet
, leaves a yellow-brown stripe on the porcelain mortar.

Black magnetic iron ore

, itself
durable and dense, attracted by a magnet
, leaves a black streak on the surface of the porcelain mortar, and has a metallic sheen.

Great, it turns out that minerals differ from each other in color, magnetic properties, line color and some other indicators.

More than 75 metals and numerous alloys based on them are widely used in modern technology. Therefore, great importance is attached to industrial methods for obtaining metals from ores. Usually, before obtaining metals from ore, it is crushed, then pre- enriched - waste rock and impurities are separated

. As a result, a concentrate is formed, which serves as a raw material for metallurgical production. The enriched ore is then converted into oxide and only after that the metal is reduced.

Metallurgy is the science of methods and processes for the production of metals from ores and other metal-containing products, the production of alloys and the processing of metals.

Depending on the method of obtaining metal from ore (concentrate), there are several types of metallurgical production.

Imagine that from one t

Of copper ore you can get
sixteen kg
of concentrate and only
four kg
of pure copper.

A branch of metallurgy such as pyrometallurgy

deals with the processing of ores, it is based on chemical reactions, in which they take place
at high temperatures
, because from the Greek.
pyros
, means fire.

Pyrometallurgical processes include roasting and smelting

During roasting,
sulfides are converted to oxides
, and
IV )
oxide .
And then the metal is reduced from the oxide
.
The resulting metal or alloy is machined and given the appropriate shape
.
In the process of separating metals ( smelting
)
II ), hydrogen, silicon, or more active metals
are used as reducing agents .

For example, even ancient metallurgists used carbon as a reducing agent to obtain iron from its ores.

.
But this method is inconvenient because the reaction between solid substances occurs only at the points of their contact.
2Fe2O3 + 3C = 4Fe + 3CO2

On an industrial scale

To obtain
iron, zinc
and other non-ferrous metals
II is used as a reducing agent .
Fe2O3 + 3CO = 2Fe + 3CO2

Now we will see how cast iron and steel

.
Iron reduction is carried out in special vertical furnaces, called blast furnaces
, with a height of up to several tens of meters and an internal volume of up to 5000 m3.
They have a steel body and are lined with fire-resistant bricks on the inside. By the nature of its operation, a blast furnace is a continuous operation apparatus
.
Solid raw materials
are fed into the furnace from above , which is a mixture of iron ore,
coke (processed coal),
limestone and other additives, and heated or oxygen-enriched air is blown in from below. At the bottom of the oven, coke burns in hot air to form carbon dioxide.

C + O2 = CO2

blast furnace

Carbon dioxide rises up in the furnace and interacts with new portions of hot coke

with the formation of carbon monoxide (II).

CO2 + C = 2CO

As a result of reactions of CO with iron (III) oxide, iron is formed.

The blast furnace process produces iron with a relatively high (more than 2%) carbon content - cast iron.

Cast iron is converted into steel by removing excess carbon by oxidation with atmospheric oxygen in special installations - open hearth furnaces, converters or electric furnaces

Converter

Hydrogen is used as a reducing agent to produce some metals.

WO3 + 3H2 = W + 3H2O

active metals that can displace other metals from their oxides and salts can also be used as reducing agents.

.
This method of producing metals is called metallothermy. If aluminum is used, then they talk about aluminothermy
:

Fe2O3 + 2Al = 2Fe + Al2O3

Iron reduction using aluminothermy is still used in rail welding.

This method of obtaining metals was proposed by a Russian scientist

N.N. Beketov.

Hydrometallurgy is a method of obtaining metals based on chemical reactions occurring in solution

. Hydrometallurgical processes include the stage of transferring insoluble metal compounds from ores into solutions, followed by the reductive separation of metals from the resulting solutions using other metals or electric current.

Electrometallurgy – methods for producing metals based on electrolysis, i.e. separation of metals from solutions or melts of their compounds using direct electric current.

This method is used
for the production of active metals
- alkali and alkaline earth metals, aluminum, and also for the production of alloy steels.
Using this method, the English chemist G. Davy
first obtained potassium, sodium, barium and calcium.

The microbiological method of obtaining metals is of great importance

.
This method uses the vital activity of certain bacteria
.
Thus, thionic bacteria
are capable of converting insoluble sulfides into soluble sulfates.
The bacterial method is used to extract copper from its sulfide ores. And then the resulting solution of copper (II) sulfate is supplied for hydrometallurgical processing. In addition, scientists have discovered that some microalgae
and bacteria accumulate certain metals (for example, gold) or their oxides on their surface. The microorganism gradually becomes overgrown with a “coat” of mineral particles and increases in size tens of times, which makes it easy to isolate the particles from the solution.

Environmental issues are of great importance in the industrial production of metals

from pollution by production waste.
Environmental protection involves, first of all, the decontamination of emissions
, for example, waste gases from iron smelting.
The main danger here is sulfur (IV) oxide formed during the processing of sulfur ores, which, when released into the atmosphere, can cause “ acid rain
”. Along with the integrated use of raw materials, the construction of treatment facilities, and the establishment of closed water use cycles, in order to protect the environment, it is necessary to move industrial enterprises outside the city limits and create forest protection areas around cities and industrial centers.

Thus, metals occur in nature in the form of compounds or in a native state.
In the earth's crust, metals are most often found in the form of compounds: oxides, silicates, carbonates, sulfides, chlorides. These compounds are found in ores and minerals. To obtain metals from ores, the ore is first crushed, enriched, converted into oxide, and only then the metal is reduced. C , CO , H2 , Si or more active metals are used as reducing agents Metallurgy deals with the production of metals and their alloys from ores. Depending on the method of obtaining metal from ore, there are several types of metallurgical production: pyrometallurgy, hydrometallurgy and electrometallurgy.