Prepared by a chemistry teacher MOU secondary school No. 1, r.p. Novospasskoe Ninasheva R.T. chemistry lesson in grade 9 Carbonic acid and its salts Let's think!
- In nature, ¾ of the volume of the Earth's surface is occupied by H2O, and CO2 is an obligatory component of the atmosphere. What is the classification of oxide? What does it form with H2O.
- Compose interaction reaction equations carbon dioxide with water and give a physicochemical description of this reaction.
- Which?
- For what?
- How will we study?
- Chemical formula- H2CO3
- Structural formula- all bonds are polar covalent
- The acid is weak, exists only in an aqueous solution, is very fragile, decomposes into carbon dioxide and water:
- CO2 + H2O ↔ H2CO3
- In ionic equations we write
- H2CO3 ↔ H2O + CO2
- Dibasic, forms salts:
- - medium - carbonates (ions CO32-)
- - acidic - bicarbonates (ions HCO3-)
- 1) Qualitative reaction to CO32-carbonate - ion "boiling" under the action of a strong acid :
- Chalk CaCO3 + 2HCl = CaCl2 + H2O + CO2- Drinking soda NaНCO3 + HCl = NaCl + H2O + CO2 2) Enter into exchange reactions with other soluble salts
- Na2CO3 + CaCl2 = CaCO3↓ + 2NaCl 3) Carbonates and bicarbonates can turn into each other
- Ca(OH)2 + CO2 = CaCO3↓ + H2O
- CaCO3 + CO2 + H2O = Ca(HCO3)2
- 4) Decomposition of bicarbonates and carbonates when heated
- NaHCO3 t˚C → Na2CO3 + H2O + CO2
- CaCO3 t˚C → CaO+CO2
Here, among the millions of crystals of calcite and aragonite, it is difficult for a person to understand
what forces of nature could create this stone miracle.
Cave "Emine-Bair-Khosar" in Crimea Stalactites and stalagmites in the cave Avshalom, Israel Stalactites and stalagmites in the cave Avshalom, Israel The use of carbonic acid salts
|
Chemical formula of a substance |
Trivial (historical) name |
Modern name |
Substance use |
|
Zinc carbonate |
Paint production. |
||
|
soda ash |
Sodium carbonate |
Water softening, glass production. |
|
|
drinking soda |
sodium bicarbonate |
In the food industry, in medicine. |
|
|
crystal soda |
Sodium carbonate decahydrate |
For softening water when washing clothes. |
|
|
Burnt magnesia |
magnesium carbonate |
In medicine. |
|
|
Mixture of MgCO3 and CaCO3 (1:1) |
Mixture of magnesium and calcium carbonates |
In construction. |
|
|
Basic copper(II) carbonate |
crafts, Jewelry. |
||
|
Potassium carbonate |
Production of glass, ceramics, cement, fertilizer. |
||
|
Chalk, marble, limestone |
Calcium carbonate |
Production building materials. |
- No. 1. Level A.
- Complete the equations of feasible chemical reactions:
- CO 2+ NaOH =
- With O2+ Na2O =
- CO2 + Ca(OH)2 =
- H2CO3+ Na2SO4 =
- CaCO3 + CO2 + H2O =
- No. 2. Level B.
- Make up the reaction equations according to the scheme:
- 2) Ca → CaC 2 → Ca (OH) 2 → CaCO 3 → CO 2 → C
- 3) CO2 → H2CO3 → Na2CO3 → CO2
- j) carbon monoxide (IV)
- l) carbon monoxide (II)
- l) nitric oxide (V) 7. Compare carbon dioxide to air
- c) lighter than air
- m) heavier than air
- y) the same 8. Strong poison, replaces oxygen in blood hemoglobin
- h) carbon monoxide (IV)
- i) carbon monoxide (II)
- j) nitric oxide (V) 9. When extinguishing fires use
- c) carbon monoxide (II)
- m) carbon monoxide (IV)
- y) nitric oxide (V)
- Study the paragraph in the textbook. To solve the task.
- What volume and mass of carbon dioxide will be released during the firing of calcium carbonate weighing 400 g.
To use the preview of presentations, create an account for yourself ( account) Google and sign in: https://accounts.google.com
Slides captions:
Do you know that…..? On April 24, 1833, carbonated soda water was patented in the United States. The first carbonated drink was obtained in 1767 by the brilliant English chemist Joseph Priestley. He discovered one of the properties of carbon dioxide, with the help of which the production of carbonated water became possible.
The composition of sparkling water Bottled sparkling water is enriched with CO 2 , which purifies water from microbes. Carbon dioxide also increases the shelf life of water and acts as a preservative. The presence of carbon dioxide in a drink or water as a preservative is marked on the label with the code E290. When carbon dioxide combines with water, carbonic acid is formed.
Carbonic acid and its salts
Carbonic acid Chemical formula - H 2 CO 3 Structural formula - all polar covalent bonds The acid is weak, exists only in aqueous solution, very fragile, decomposes into carbon dioxide and water: CO 2 + H 2 O ↔ H 2 CO 3 In ionic equations we write H 2 CO 3 ↔ H 2 O + CO 2
Carbonic acid Dibasic, forms salts: - medium - carbonates (ions CO 3 2-) - acidic - hydrocarbonates (ions H CO 3 -)
Salts of carbonic acid are crystalline solids. most of them do not dissolve in water. Dissociation: with the formation of carbonate anions, hydrocarbonates are solid crystalline substances. dissolve in water Dissociation: with the formation of a hydrogen cation, a carbonate anion.
Chemical properties of carbonates and hydrocarbonates 1) Qualitative reaction to CO 3 2-carbonate - ion "boiling" under the action of a strong acid: Chalk Ca CO 3 + 2HCl \u003d C aCl 2 + H 2 O + CO 2 Baking soda Na H CO3 + HCl \u003d NaCl + H 2 O + CO 2 2) Enter into exchange reactions with other soluble salts Na 2 CO 3 + CaCl 2 = CaCO 3 ↓ + 2 NaCl 3) Carbonates and bicarbonates can turn into each other Ca (OH) 2 + CO 2 \u003d CaCO 3 ↓ + H 2 O CaCO 3 + CO 2 + H 2 O \u003d Ca (HCO 3) 2 4) Decomposition of bicarbonates and carbonates when heated NaHCO 3 t˚C → Na 2 CO 3 + H 2 O + CO 2 CaCO 3 t ˚ C → CaO + CO 2
for carbonates, bicarbonates CaCO 3 NaHCO 3 Qualitative reactions To check the presence of carbonates, you need to add any acid CaCO3 + 2H+ ↔ Ca2+ + H2O + CO2 chalk Baking soda
The Red Cave, or Kizil-Koba, is the largest of 800 Crimean caves. It is located 3.5 km from the village of Perevalnoye in the picturesque Kizil-Koba tract, which is a natural monument and is protected by the state. The total length of the studied part of the cave is 14 km. The part that has not been passed between the Proval cave and the Fifth landslide hall is about 3.5 km more. Kizil-Koba is a complex, intricate labyrinth, located on six floors with an amplitude of 135 m. The oldest sixth floor is about two million years old.
stalagmites
Stalactite "Pot-bellied"
Stalactite "Fire"
Cave "Emine-Bair-Khosar" in Crimea
Stalactites and stalagmites in the cave of Avshalom, Israel
Application of salts of carbonic acid Chemical formula of the substance Trivial (historical) name Modern name Application of the substance ZnCO 3 Galmei Zinc carbonate Production of paints. Na 2 CO 3 Soda ash Sodium carbonate Water softening, glass production. NaHCO 3 Baking soda Sodium bicarbonate In the food industry, in medicine. Na 2 CO 3 ·10H 2 O Soda crystalline Sodium carbonate decahydrate For softening water when washing clothes. MgCO 3 Burnt magnesia Magnesium carbonate In medicine. Mixture of MgCO 3 and CaCO 3 (1:1) Dolomite Mixture of magnesium and calcium carbonates In construction. (CuOH) 2 CO 3 Malachite Basic copper (II) carbonate Crafts, jewelry. K 2 CO 3 Potash Potassium carbonate Production of glass, ceramics, cement, fertilizer. CaCO 3 Chalk, marble, limestone Calcium carbonate Manufacture of building materials.
Bozadzhi N.M.
chemistry teacher
Tell me and I will forget
Show me and I will remember
Involve me and I will learn!
Chinese wisdom
Target: After reading the fragment, choose the correct answer by writing the letter of the correct answer and as a result - the topic of our lesson!
1. Coal is the most valuable of minerals, - the engineer replied, - and nature seems to have decided to prove this by creating a diamond, because it is, in essence, nothing more than crystalline carbon.
J. Verne "Mysterious Island"
K) graphite
A) carbine
P) fullerene
2 .Meanwhile, the Needlewoman returns, strains the water, pours it into jugs, and what an entertainer: if the water is unclean, she will fold a sheet of paper, put coals in it and pour coarse sand, insert that paper into a jug and pour water into it, and water - then, you know, it passes through the sand and through the coals and drips clean, like crystal, into a jug.
Russian folk tale"Moroz Ivanovich"
B) filtration
BUT) distillation
O) adsorption
M) crystallization
3. Carbon monoxide! cried Holmes. “Wait a little. Now he will leave.
Looking through the door, we saw that the room was lit only by a dim blue flame, flickering in a small copper brazier in the middle ... A terrible poisonous fumes wafted through the open door, from which we choked and coughed.
A.K. Doyle "The Case of the Translator"
3. Find chemical errors in the read passage. Why couldn't Holmes and his companions determine the presence of carbon monoxide in the room by the signs described?
H) carbon monoxide is odorless
G) carbon monoxide has a pleasant smell
BUT) When you have carbon monoxide poisoning, you don't cough
4. A tree grows in the Arabian desert caratina silikva (caratina siliqua), the fruit stones of which always have the same weight in any year and on any tree. Therefore, the jewelers of antiquity used such weights for their scales, calling them carats. Nowadays, there is a carat test of gold and precious stones.
AND) 100 g
H) 0.5 g
T) 0.2 g
R) 0.1 g
5 . - Have you heard about the "dog cave" effect in Italy? There is a cave there. The person will enter and walk around, and the dog or rabbit will die in a few minutes.
- Why?
- Carbon dioxide is released from a volcanic fissure...
V. Korotkevich "Black Castle Olshansky"
S) SO 2 heavier than air and accumulates at the bottom
BUT) SO 2 safe for humans but harmful to animals
AND) a man enters a cave wearing a gas mask
5. Why does a person remain alive in the “dog cave”, while dogs and other small animals die?
- Questions
1 2 3 4 5
K A R B O N A T Y
- What carbonates ? cabonates - these are salts of carbonic acid, which will be the subject of discussion in today's lesson.
As a result of studying the topic, you will be able to:
- giving characterization of coal
- giving characterization of coal
acid and its properties .
2. Simulate
3. Consider
4. Simulate
5. Write reaction equations
6.Exercise reflection of their activities
- acid and its properties . 2. Simulate methods for producing carbonic acid 3. Consider properties of salts of carbonic acid. 4. Simulate qualitative reaction to the carbonate ion 5. Write reaction equations 6.Exercise reflection of their activities
- Carbonic acid - weak dibasic acid with chemical formula H 2 CO 3
Exercise 1. Write reaction equations
stepwise dissociation of carbonic acid:
H 2 CO 3 H + + HCO 3 -
HCO 3 - H + + CO 3 2 -
H 2 CO 3 2H + + CO 3 2 -
NB! dibasic, forms 2 types of salts:
medium - carbonates (ions CO 3 2- )
acidic - hydrocarbons (HCO ions 3 - )
- Carbonic acid is unstable, not isolated in its pure form, as it easily decomposes into carbon dioxide and water (the process is reversible)
H 2 CO 3 CO 2 +H 2 O
An experience
1. Dissolving carbon dioxide in water
CO2 + H2O H2CO3
2. Interaction of salts (carbonates and bicarbonates) with stronger acids .
NaHCO 3 +HCI=
Na 2 CO 3 +2HCI=
IV. Salts of carbonic acid and their solubility
Chemical formula
Name
Solubility
soda ash
drinking soda
Chalk, marble, limestone
1) Interaction of bicarbonates with acids
Na H CO 3 + HCl =
drinking
soda
2) Enter into exchange reactions with other soluble salts
Na 2 CO 3 + CaCl 2 =
NaCl + H 2 O + CO 2
CaCO 3 ↓ + 2 NaCl
Chemical properties of carbonates and hydrocarbonates
3) Carbonates and bicarbonates can turn into each other
CaCO 3 + CO 2 + H 2 O \u003d Ca (HCO 3 ) 2
Ca(HCO 3 ) 2 = CaCO 3 + CO 2 + H 2 O
4) Decomposition of bicarbonates and carbonates when heated
NaHCO 3 t˚C → Na 2 CO 3 + H 2 O+CO 2
CaCO 3 t ˚ C → CaO + CO 2
Exception:
metal carbonates I groups, ch. subgroups
Chemical properties of carbonates and hydrocarbonates
Hydrocarbons cause temporary hardness of water.
Ways to eliminate temporary hardness of water:
1. Boiling
When boiled, soluble calcium and magnesium bicarbonates are converted into insoluble carbonates.
2. Adding soda ( Na 2 CO 3 )
Eliminates not only temporary, but also permanent hardness of water created by chlorides and sulfates of calcium and magnesium.
VI. Determination of carbonates
Determination of carbonate - ions
CaCO 3 + 2HCI \u003d CaCI 2 + H 2 CO 3
CO 2 + Ca(OH) 2 \u003d CaCO 3 ↓ + H 2 O
VII. Importance of carbonates
- Among carbonates, calcium carbonate deserves special attention. CaCO3 , met as:
limestone marble chalk
VII. Importance of carbonates
Three brothers live on earth
From the carbonate family.
Elder brother - handsome - Marble,
Glorious in the name of Karara,
Excellent architect. He
He built Rome and the Parthenon.
Everyone knows Limestone,
That's why it's named like that.
Famous for his work
Building a house behind the house.
VII. Importance of carbonates
And able and able
The younger soft brother Mel.
How to draw, look
This CaCO 3 .
Brothers love to frolic
Burn in a hot oven.
CaO and CO 2 are formed then.
It's carbon dioxide
Each of you is familiar with him,
We breathe it out.
VII. Importance of carbonates
Well, this is CaO -
hot burnt
LIME FAST.
Add water to it
mixing carefully,
To avoid trouble
protect hands.
Cool mixed LIME,
but DONE!
milk of lime
magnified.
VII. Importance of carbonates
The bright house cheered up
Turning lime into chalk.
Hocus pocus for the people:
One has only to blow through the water,
How easily it turns into milk!
And now I'm getting a soda rather deftly:
Milk plus vinegar, Ay!
Foam pours over the edge!
All in worries, all in work
From dawn to dawn -
These brothers the Carbonates,
Chemical formula of a substance
Trivial (historical) name
Modern name
Application
substances
Zinc carbonate
soda ash
drinking soda
Paint production.
Na 2 CO 3 10H 2 O
Sodium carbonate
crystal soda
Water softening, glass production.
sodium bicarbonate
In the food industry, in medicine.
Sodium carbonate decahydrate
Mixture of MgCO 3 and CaCO 3 (1:1)
Burnt magnesia
For softening water when washing clothes.
magnesium carbonate
In medicine.
Mixture of magnesium and calcium carbonates
In construction.
Basic copper(II) carbonate
Crafts, jewelry.
Potassium carbonate
Chalk, marble, limestone
Production of glass, ceramics, cement, fertilizer.
Calcium carbonate
Production of building materials.
Reflection
Exercise 1. Write the reaction equation for the preparation of calcium carbonate from calcium hydroxide
Ca(OH) 2 +CO 2 = CaCO 3 + H 2 O
Task 2. How to get calcium bicarbonate from calcium carbonate? Write the reaction equation.
CaCO 3 ↓ +H 2 O+CO 2 = Ca(HCO 3 ) 2
Exercise 3 . Is the reverse transformation possible? If so, what are the methods of transformation.
t 0
Ca(HCO 3 ) 2 = CaCO 3 + H 2 O+CO 2
Ca(HCO 3 ) 2 + Na 2 CO 3 =CaCO 3 +2NaHCO 3
Exercise 4 . Set the correspondence between the left and right sides of the equations
right parts
equations
a) K 2 SO 4 + 2CO 2 + 2H 2 O
b) Ca(HC O 3 ) 2
in) K 2 CO 3 + CO 2 + H 2 O
G) CaO+CO 2
e) 2NaCl + CO 2 + H 2 O
left hand sides of equations
t o
1 ) 2KHCO 3 →
t o
2)CaCO 3 →
3) Na 2 CO 3 + 2HCI →
4) FROM aCO 3 +CO 2 +H 2 O →
5)2KHCO 3 + H 2 SO 4 →
Answer: 1 - in; 2 -d; 3d; 4-b; 5-a
1. At the lesson I worked ... 2. With my work in the lesson, I ... 3. The lesson seemed to me ... 4. For the lesson I ... 5. My mood… 6. The material of the lesson was ...
active, satisfied, short, not tired, useful, better, understandable, interesting, easy.
- Read and study the abstract.
- Repeat paragraph: § 4.14.2
- Complete tasks:
work in groups exercise 1 (9-15) p.112
4 1s21s2 2s22s2 2p Electronic structure
5 So, carbon: d) oxidation states -4.0, +2, +4 d) oxidation states -4.0, +2, +4 e) oxides - CO (does not form acids) - carbon monoxide, carbon monoxide, carbon monoxide II e) oxides - CO (does not form acids) - carbon monoxide, carbon monoxide, carbon monoxide II CO 2 (acid-forming) - carbon dioxide, carbon dioxide, carbon monoxide IV CO 2 (acid-forming) - carbon dioxide, carbon dioxide, carbon monoxide IV e) forms a huge number of compounds with hydrogen, the simplest CH 4 is methane e) forms a huge number of compounds with hydrogen, the simplest CH 4 is methane
7 Crystal lattice of graphite Graphite is characterized by a hexagonal crystal lattice. Consists of parallel layers formed by regular hexagons of carbon atoms. Graphite has a hexagonal crystal lattice. Consists of parallel layers formed by regular hexagons of carbon atoms.
8 greasy to the touch substance of black or gray color with a metallic luster, refractory (melts under pressure of 105 atm and at temperatures above 3700 ° C), electrically conductive, soft, easily delaminates. greasy to the touch substance of black or gray color with a metallic sheen, refractory (melts under pressure of 105 atm and at temperatures above 3700 ° C), electrically conductive, soft, easily delaminates. Graphite is used to make fire-resistant products that are resistant to alkalis and molten systems; molds are coated with graphite to prevent mold earth from sticking to the product; produce electrical products, pencils, paints, lubricants, anti-friction materials and products. Graphite is used in nuclear technology as a neutron moderator, insulating material. Graphite is used to make fire-resistant products that are resistant to the action of alkalis and molten systems; molds are coated with graphite to prevent mold earth from sticking to the product; produce electrical products, pencils, paints, lubricants, anti-friction materials and products. Graphite is used in nuclear technology as a neutron moderator, insulating material Graphite modifications, often found in nature - coke, soot. charcoal. Modifications of graphite, often found in nature - coke, soot. charcoal.
9 colorless crystalline substance with an atomic lattice. colorless crystalline substance with an atomic lattice. Each carbon atom in a diamond is surrounded by four others located from it in directions from the center of the tetrahedron to its vertices. Each carbon atom in a diamond is surrounded by four others located from it in directions from the center of the tetrahedron to its vertices. Diamond has a high hardness, a density of 3.5 g/cm2, is a poor conductor of heat and practically does not conduct electricity. Diamond has a high hardness, a density of 3.5 g/cm2, is a poor conductor of heat and practically does not conduct electricity. In its pure form, diamond strongly refracts light. In its pure form, diamond strongly refracts light. It is used as a decoration, as well as for cutting glass, drilling rocks and grinding especially hard materials. It is used as a decoration, as well as for cutting glass, drilling rocks and grinding especially hard materials. DIAMOND
10 Mutual transformation of diamond and graphite Under enormous pressure, graphite turns into diamond, and vice versa at high temperatures, diamond turns into graphite Under great pressure, graphite turns into diamond, and vice versa at high temperatures, diamond turns into graphite
12 a) forms carbides with metals 4Al+3C=Al 4 C 3 (when heated) 4Al+3C=Al 4 C 3 (when heated) Ca+2C=CaC 2 (when heated) Ca+2C=CaC 2 (when heated ) b) with hydrogen C + 2H 2 \u003d CH 4 (methane) (when heated) C + 2H 2 \u003d CH 4 (methane) (when heated) Properties of the oxidizing agent:
13 Reductant properties c) reduces metals from their oxides c) reduces metals from their oxides a large amount of heat 2C + O 2 \u003d 2CO + Q 2C + O 2 \u003d 2CO + Q C + O 2 \u003d CO 2 + Q C + O 2 \u003d CO 2 + Q
14 Carbonic acid and its salts Lesson objectives: To introduce students to the features of carbonic acid; with its main natural compounds; repeat the concepts: acid and medium salts on the example of carbonates and bicarbonates and their technical names. To study the chemical properties of salts of carbonic acid and their main areas of application.
16 In G.R. Haggard “Cleopatra” we read: “... she took one of the 3 huge pearls out of her ear and lowered the pearl into ...? There was silence, the shocked guests, frozen, watched how the incomparable pearl slowly dissolved, There was no trace of it left, and then Cleopatra raised the goblet, twisted it, shaking it, and drank everything to the last drop. : “... she took one of the 3 huge pearls out of her ear and lowered the pearl into ... ? There was silence, the shocked guests, frozen, watched how the incomparable pearl slowly dissolved, There was no trace of it left, and then Cleopatra raised the goblet, twisted it, shaking it, and drank everything to the last drop.
20 Reaction equation Reaction equation CO2 (g) + H2O (l) H2CO3 (l) + Q CO2 (g) + H2O (l) H2CO3 (l) + Q non-catalytic non-catalytic
27 B) Hydrocarbonates - acid salts NaHCO 3 - baking soda, sodium carbonate sour, baking soda NaHCO 3 - baking soda, sodium carbonate, baking soda Ca (HCO 3) 2 - calcium bicarbonate (temporary water hardness) Ca (HCO 3) 2 - calcium bicarbonate (temporary hardness of water)
28 3. Chemical properties of carbonates and hydrocarbonates A) Elimination of temporary hardness of water by boiling A) Elimination of temporary hardness of water by boiling limestone calcination B) Thermal decomposition, e.g. limestone calcination CaCO3=CaO+CO2 CaCO3=CaO+CO2
29 Write the reaction equations C) Dissolution of drinking soda C) Dissolution of drinking soda D) “Bubbling up” of baking soda under the action of acids Interactions of drinking soda with hydrochloric acid
30 Qualitative reactions to carbonates and bicarbonates: - When carbonates and bicarbonates interact with acids, "boiling" occurs - the release of carbon dioxide bubbles - When carbonates and bicarbonates interact with acids, "boiling" occurs - the release of carbon dioxide bubbles
40 Think! What role does baking soda play when it is drunk for heartburn? (The German doctor was the first to use a solution of sodium bicarbonate for heartburn, by whose name this substance at one time was even called "Bulrich's salt") In the human stomach there is HCl, which neutralizes soda: NaHCO3 + HCl NaCl + CO2 + H2O.
43 Test option 1 1. Which reaction does not proceed to the end? a) H2O + CO2 =... ; b) CaO + CO2 =...; c) KOH + CO2 =...; d) K2CO3 + CO2 + H2O = What is the valency of carbon in carbonic acid H2CO3: a) II; b) IV; c) III; d) VI. 3. For the reaction CaCO3 \u003d CaO + CO2 necessary condition is: a) cooling; b) grinding of the initial CaCO3; c) the presence of a catalyst; d) heating. 4. Select the series corresponding to the decreasing strength of acids: a) H2SO4, H3PO4, H2CO3; b) H2SO4, H2CO3, H3PO4; c) H3PO4, H2SO4, H2CO3; d) H2CO3, H3PO4, H2SO4. 5. Acid salts of carbonic acid are called: a) nitrates; b) carbonates; c) bicarbonates; d) carbides.
44 Test option 2 1. Which characteristic refers to carbonic acid: a) unstable b) monobasic c) strong d) organic The condition necessary for the decomposition of carbonates: a) pressure b) temperature c) light d) water 4. The substance by which carbonates are recognized: a) HCl b) Ca (OH) 2 c) BaCl2 d) CO2 soda? a) in the confectionery business b) in construction c) in the production of glass d) obtaining fertilizers
45 Answers option 1 1. Which reaction does not proceed to the end? a) H2O + CO2 =... ; b) CaO + CO2 =...; c) KOH + CO2 =...; d) K2CO3 + CO2 + H2O = What is the valency of carbon in carbonic acid H2CO3: a) II; b) IV; c) III; d) VI. 3. For the reaction CaCO3 = CaO + CO2 to proceed, the necessary condition is: a) cooling; b) grinding of the initial CaCO3; c) the presence of a catalyst; d) heating. 4. Select the series corresponding to the decreasing strength of acids: a) H2SO4, H3PO4, H2CO3; b) H2SO4, H2CO3, H3PO4; c) H3PO4, H2SO4, H2CO3; d) H2CO3, H3PO4, H2SO4. 5. Acid salts of carbonic acid are called: a) nitrates; b) carbonates; c) bicarbonates; d) carbides
46 Answers option 2 1. Which characteristic refers to carbonic acid: a) unstable b) monobasic c) strong d) organic The condition necessary for the decomposition of carbonates: a) pressure b) temperature c) light d) water 4. The substance by which carbonates are recognized: a) HCl b) Ca (OH) 2 c) BaCl2 d) CO2 soda? a) in the confectionery business b) in construction c) in the production of glass d) obtaining fertilizers