No matter how long the road is, you can go on step by step, no matter how short the road is, you can't go without taking your feet. The following is the final examination paper (with answers) of the first volume of Grade 20 16-20 17 chemistry compiled by me. Let's have a look.

I. Multiple choice questions (only one correct answer) (30 points in total)

1. Substances that will not cause air pollution are

A.pm2.5b Carbon monoxide C. Nitrogen D. Sulfur dioxide

2. The following changes belong to chemical changes.

A. drying wet clothes B. burning magnesium tape C. melting paraffin D. juicing oranges.

3. Indium tin oxide is an important material of touch screen, which is made by melting tin oxide and indium oxide. In indium oxide (In2O3), the valence of indium element (in) is

A.0 B.+3 C.+2 D.+6

4. What is pure is

A. vinegar B. seawater C. liquid oxygen D. clean air

5. The following chemical terms are correct.

A.2 hydrogen molecule? 2H B.3 oxygen atom? O3 C. Water molecules? D.+ 1 valence sodium element?

6. Can be mixed with water, after full oscillation can get the solution of the material is

A. milk powder B. sucrose C. vegetable oil D. ice cubes

7. In the illustrated experimental operation, it is correct that

A. take a small amount of liquid. B. smell the gas. C. light the alcohol lamp. D. heat the liquid.

8. The statement about air is correct.

A. air is composed of air molecules.

B. the chemical properties of nitrogen and oxygen in the air have changed after mixing.

C separating liquid air to produce oxygen is a decomposition reaction.

Air is a mixture of nitrogen and oxygen.

9. The chart below shows the pH values of some common substances in life. According to the chart, the following statements are correct.

A. Soy sauce is alkaline. B. Toothpaste is acidic.

C. People with hyperacidity can drink more corn porridge D. Watermelon juice is more sour than apple juice.

10. Burning in oxygen produces bright blue-purple flame and gas with pungent smell.

A. Charcoal B. Methane C. Sulfur D. Red phosphorus

1 1. The following chemical equations are written correctly.

A.H2+ O2 H2O B.H2SO4+NaOH？ Tetrasodium H2O salt

C.CuSO4+2NaOH？ Cu(OH)2+2H2O d . 2 kmno 4 k2mno 4+MnO 2+O2？

12. Neon lights make our life bright and colorful. The gas filled in neon lights is

A. oxygen b nitrogen c rare gas d carbon dioxide

13. The nature of a substance determines its use. The following uses are mainly based on its chemical properties.

14. It can represent both elements, atoms and chemical symbols of substances.

A. copper, boron, nitrogen dioxide, carbon, nitrogen and sulfur dioxide

15. installing catalytic converter in automobile exhaust pipe can reduce exhaust pollution, and its reaction principle is 2CO+2NO 2X+N2, where the chemical formula of x is

A.NO2 B.CO2 C.H2O

16. The decomposition reaction is

A.Fe + CuSO4？ FeSO4 + Cu B.2H2O2 2H2O+O2？

C. Cao+H2O? Ca(OH)2 D. NaOH + HCl？ Sodium chloride+H2O

17. In the laboratory, hydrogen peroxide, potassium chlorate and potassium permanganate can all be used to make oxygen. What they have in common is that

A. Both belong to oxides B, all contain oxygen C, and all molecules D contain oxygen.

18. Water is the source of life. Someone drank 9 grams of H2O, in which the number of water molecules is

A.3.0 1？ 1023 B.6.02？ 1023 C.9？ 6.02? 1023 D.3？ 6.02? 1023

19. The calligraphy and painting written or painted by some ancient painters can be preserved for a long time without discoloration because.

A. the quality of paper is very good. The chemical properties of carbon are relatively stable at room temperature.

C. correct preservation method D. carbon will not react with other substances under any conditions.

20. The following gas mixtures may explode in case of open flame.

A.H2, CO2, CO2, H2, CO2, N2

2 1. What is wrong in the statement about catalyst is that

A. the catalyst can change the chemical reaction speed of other substances. B. the role played by the catalyst is called catalysis.

C the mass of the catalyst will become smaller after chemical reaction d, and the chemical properties of the catalyst will not change before and after chemical reaction.

22. Identify the following material groups that belong to allotropes.

A. ice and water carbon monoxide and carbon dioxide

C. Water and hydrogen peroxide D. Red phosphorus and white phosphorus

23. When heated slightly in a closed container, the pure substance X is decomposed into NH3, H2O and CO2. According to this experimental fact, we can draw a conclusion.

A.x consists of four elements. The chemical properties of B. X are very stable. There is water in C. X, and D. X is oxide.

24. Chemical change refers to the generation of new substances.

A. atoms recombine into molecules to produce new elements. B. Molecules split into atoms to produce new atoms.

C. Some substances are different in composition or structure from the original substances. D. there are new molecules with the same composition and structure.

25. The following facts have been misinterpreted.

The fragrance molecules outside the flowering wall of wall A are constantly moving.

BHH _ 2O _ 2 can kill bacteria, but H _ 2O cannot have different molecular composition.

The size of mercury atom in C thermometer changes when it expands with heat and contracts with cold.

D 50mL water mixed with 50mL alcohol, the total volume is less than 100mL, and there are gaps between molecules.

26. After the chemical equation A C2H2+B O2 H2O+D CO2 is balanced, the values of A, B, C and D are as follows.

A.2、5、2、4 B. 1、2、 1、2C.4、5、2、4 D. 1、3、 1、2

27.N(NO2)3 is the raw material of a new rocket propellant discovered by scientists in 20 1 1 year. The following statement is correct.

The mass ratio of n and o elements in A.N(NO2)3 is 14: 138b. The atomic ratio of nitrogen to oxygen in N (NO2) 3 is 4: 6.

The mass fraction of nitrogen in C.N. (NO2) 3 is 18.4%, and the molar mass of D.N. (NO2) 3 is 152.

At 28.25℃, KNO3 solid is gradually added to a certain amount of unsaturated KNO3 solution, and the following figure can correctly show the change law of solute quality in this process.

29. 1g oxygen contains n O2 molecules, so Avogadro constant can be expressed as

a . 32n b .( 1/32)n c . 16n d .( 1/ 16)n

At 30.60℃, the solubility of a and b is a.

At 30℃, the solubility of a and b must be a.

B At 30℃, the mass fraction of solute in the saturated solution of A and B must be A = B..

C.a >； 30℃, if the solubility is a >; B, the crystal quality must be m.

At 30℃, if the solubility is

Two. Fill in the blanks (40 points in total)

3 1. Chemistry is around us and closely related to our life and production. Please use your chemical knowledge to answer the following questions:

1. Common substances are as follows: A, oxygen B, carbon dioxide C, salt D, activated carbon E and sodium carbonate. Please fill in the blanks with the names or chemical formulas of the above substances: (1) used as fire extinguishing agent for electrical appliances, (2) used for human breathing, and (3) used as seasoning in life.

Ⅱ. The right picture is a schematic diagram of the gas water heater. The water heater uses natural gas (mainly methane).

For gasoline. ① Write the chemical equation of complete combustion of CH 4: (4);

2 When? Air intake? The chemical formula of toxic gas M produced by partial blockage and incomplete combustion is (5).

ⅲ. Athletes need physiological saline to replenish water and electrolytes, and they will also add appropriate amount of glucose (C6H 12O6) to the physiological saline to replenish energy in time. The solute of physiological saline is (6); The molar mass of glucose is (7), and the mass fraction of carbon in glucose is (8).

Water plays a very important role in life, production and chemical experiments.

First, the main production steps of a water plant are: river water? One (alum)? B (precipitation)? C (filtration)? D (adding liquid chlorine)? Clean water. Alum [chemical formula is KAl(SO4)2? The function of 12H2O] is (9), and the name of the atomic group contained in alum is (10); The purpose of adding liquid chlorine is (1 1).

Ⅱ. The experiment of electrolytic water is shown on the right. The gas generated in glass tube A is (12).

The method of testing this gas is (13).

The chemical reaction diagram of electrolytic water is as follows:

The correct information that can be obtained from the schematic diagram is (14) (fill in the number).

A. There are 6 kinds of atoms and 4 kinds of molecules before and after the reaction. B. There are three elements before and after the reaction.

C. The essence of chemical change is the recombination of atoms. D. Molecules are the smallest particles in chemical change.

E. In this chemical reaction, the number ratio of hydrogen and oxygen is 2 ∶ 1 F, and water is composed of hydrogen and oxygen.

The chemical equation of electrolytic water is (15).

33. The picture shows some important experiments in junior middle school chemistry. Please answer the following questions:

Write the chemical equation of red phosphorus burning in air in Experiment A (16). ..

This experiment is only a rough method to measure the oxygen content in the air. The possible reason why you think this experiment is inaccurate is (write one of them) (17).

Two. In experiment B, the phenomenon of iron wire burning in oxygen is (18), and the chemical equation is written as (19).

The purpose of putting a little water or spreading a layer of fine sand at the bottom of the experimental bottle is (20).

ⅲ. Experiment C The purpose of coating a layer of clear limewater on the inner wall of the beaker is (2 1), and the chemical equation (22) of the reaction is written.

34. The solubility information of substance A is shown in the following table. The process of continuously adding solid A to 100g water or changing the temperature to obtain the corresponding solution ① ⑤ is shown in the right figure. According to the solubility data and the experimental process, answer the following questions.

Draw the solubility curve of substance A .. (23)

Ⅱ. At 25℃, the solubility of substance A is about (24) g;

The saturated solution in solution ① ⑤ is (25) (fill in the number). The solute mass fraction of solution ③ is (26).

Ⅲ. Solution ⑤ can be cooled to 30℃, and substance A _ (27) g can be precipitated.

35. Nano-ultrafine calcium carbonate is a new type of ultrafine solid material, which is an important filler in rubber, plastic products, paper making, coatings, ink and other industries. The process of preparing nanometer ultrafine calcium carbonate from limestone in industry is as follows. Please answer the following questions:

I. The chemical equation of the reaction in the calciner is (28). Operations 1 and 2 are similar to those in the laboratory (29).

Ⅱ. The basic reaction type in the sedimentation tank belongs to (30). Lime milk is generally made by adding water to calcium oxide. If there is undissolved calcium hydroxide, the lime milk is (3 1) (fill in: solution, suspension, emulsion).

Three. The chemical formula of the substance that can be recovered in the above process is (32).

Three. Short answer questions (30 points in total)

36. Answer the questions according to the equipment shown in the picture below.

1. Write the name of the marked instrument: A (1); B (2)

Ⅱ. The reason why the test tube mouth in device A is slightly inclined downward is (3).

Three. With marble and dilute hydrochloric acid, carbon dioxide can be controlled. The optional generating device and collecting device are (4) (filled in letters, the same below), and the chemical equation (5) of this reaction is written.

Ⅳ. The solid mixture of anhydrous sodium acetate and alkaline lime is heated in the laboratory to prepare water-insoluble methane gas. The optional generating device and collecting device are (6).

37. A classmate makes oxygen, and the process of recovering and purifying potassium chloride and manganese dioxide is as follows.

Answer the following questions:

Write the chemical equation (7) of oxygen produced in the above process.

Two. The purpose of adding appropriate amount of water in step 2 (8) (fill in the label).

A. improve experimental efficiency B. ensure solid 1 complete dissolution C. accelerate solid dissolution D. reduce solid loss 2.

Ⅲ. Operation n in step Ⅳ should choose (9) (fill in? Answer?

Or? b？ ) device, the role of glass rod in this operation is (10).

Ⅳ. After the experiment, the quality of recovered manganese dioxide is higher than the original one.

Potassium chlorate is large, and the possible reason is (1 1) (write a little).

38. The students in the interest group used the device shown in figure A below to carry out the reaction experiment of copper oxide with enough carbon powder to explore the composition of the generated gas.

1. According to the analysis of the experimental device, the students in the interest group assume that there is only carbon dioxide; ② ( 12) ; ③ Only carbon monoxide. Write the chemical equation (13) of the reaction in hypothesis 1. The chemical formula of the oxidant in this reaction is (14).

Ⅱ. At the beginning of the experiment, first turn on K, slowly introduce nitrogen for a period of time, and then turn off K, with the purpose of (15).

Ⅲ. The experimental phenomenon observed in equipment B is (16); The function of device C is (17).

Ⅳ. If obvious changes are observed in devices B, D and E, the conclusion is (18).

39. A classmate takes 2.5g limestone and drops 30g dilute hydrochloric acid. The relationship between the quality of generated gas and the quality of dripping hydrochloric acid is shown in the following figure. Try to calculate according to the data in the figure:

The amount of carbon dioxide produced by the reaction is (19) mol.

Ⅱ. Mass fraction of calcium carbonate in limestone (calculated according to chemical equation).

(20)

ⅲ. After the reaction, litmus test solution was added dropwise to the obtained solution, and the observed phenomenon was (2 1).

Reference answer

First, multiple-choice questions (65438+ 0 points for each question, a total of 30 points)

No.1234567891012131415.

Answer C B B C D B D D C C D C D A B

No.161719 202122 23 24 25 26 27 28 29 30

Answer b, b, b, b, b, c, c, c, c, c, c, c.

Note: Unless otherwise specified, each blank is given 1 minute. Chemical equations are all 2 points, chemical formula errors are not given points, reaction conditions are omitted, the state is unbalanced, and the total score of each major question is 1 minute).

2. Fill in the blanks This question contains 5 small questions, with a total score of 42 points.

3 1 question, with a total score of 10

3 1( 1) CO2 1

3 1(2) oxygen 1

3 1③ salt 1

3 1(4) CH4+2O2 CO2+2H2O

2

3 1(5) CO 1

3 1(6) sodium chloride 1

31(7)180g/mol

3 1(8) 40% 1

32 questions, a total of 9 points

32(9) Removal of suspended solids 1

32( 10) sulfate 1

32( 1 1) disinfection and sterilization 1

32( 12) O2 1

32( 13) Use a Martian slat to see if it is rekindled 1.

32( 14) C E 2

32( 15) 2H2O 2H2？ +O2？ 2

Total of 33 questions 10.

33( 16) 4P

2

33( 17) air leakage of the device (other reasonable points are also given) 1.

33( 18) Mars is everywhere, producing a black solid 1.

33( 19) 3Fe+2O2 Fe3O4

2

33(20) Prevent spilled melt from breaking the bottom of the bottle 1

33(2 1) CO2 1 produced by the test.

33(22) Ca(OH)2+CO2？ CaCO3？ +H2O 2

34 questions, a total of 6 points

34(23) 1

34(24) 39.3g 1

34(25) ②⑤ 2

34(26) 29.28% 1

34(27) 9g 1

35 questions, 7 points in total.

35(28) CaCO3 CaO+CO2？

2

35(29) filter 1

35(30) combination 1

35(3 1) suspension 1

35(32) New Protocol of Carbon Dioxide H2O

3. The short answer questions contain 4 small questions, with a total score of 28 points.

36 questions, a total of 9 points

36( 1) alcohol lamp 1

36(2) Long-necked funnel 1

36(3) Prevent the condensed water from flowing backwards, so that the test tube is broken 1.

36(4) C F 2

36(5) CaCO3+2HCl？ Calcium chloride +H2O+ carbon dioxide? 2

AD 36 or AD 2.

37 questions, 7 points in total.

37(7) 2KClO3 2KCl+3O2？

2

37(8) A B 2

37(9) B 1

37( 10) Stir the solution to prevent splashing.

37( 1 1) was not cleaned and mixed with KCl (or not completely dried) 1.

38 questions, a total of 8 points

38( 12) carbon dioxide and carbon monoxide 1

38( 13) C+2CuO 2Cu+CO2？

2

38( 14) CuO 1

38( 15) Vent the air in the device with nitrogen to prevent interference with the detection of carbon dioxide 1.

38( 16) clarified limewater becomes turbid 1

Absorb and remove carbon dioxide 1

38( 18) Assumption ② holds 1

39 questions, a total of 4 points.

39( 19) 0.02 1

Solution 39(20): Let the amount of calcium carbonate be x moles.

CaCO3+2HCl？ Calcium chloride +H2O+ carbon dioxide?

1 2 1 1

x 0.02

X=0.02 (mole)

CaCO3%=0.02？ 100/2.5=80%

A: The mass fraction of calcium carbonate is 80%.

1

1

39(2 1) litmus test solution changed from purple to red 1.

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