Variant 3

Choose one correct answer and write a number in the answer form to the right of the number of the corresponding assignment. For corrections, use the following cell on the right

1.  The number of electrons in an argon atom is equal to the number of electrons in the ion

                  1) S^2-                              2) Al³⁺                             3) Na⁺                               4) F^-

2.  In which series are simple substances arranged in order of strengthening their metallic properties

         1) Ве→В→С                  2) Al→Si→H                3) Ca→Mg→Be              4) Na→K→Rb

3.  The degree of oxidation of +5 phosphorus is manifested in the compound, the formula of which

5.  The substance Cа (НCО)₃ belongs to the following class of inorganic substances

1)  acid salt             3) middle salt

2)  basic salt           4) hydroxide

6.  Copper reacts with a dilute solution of each of the two substances

1)  hydrochloric acid and nitric acid         3) sulfuric acid and hydrochloric acid

2)  nitric acid and silver nitrate     4) hydrochloric acid and silver nitrate

7.  Barium oxide can react

1)  Р₂О₅     2) FeO             3) N₂О            4) СО

8.  The precipitate is formed when the solutions are drained off

1)  sodium carbonate and hydrochloric acid    3) sodium hydroxide and barium nitrate

2)  sodium bromide and potassium hydroxide          4) strontium chloride and sulfuric acid

9.      The transformation of Cu (OH)₂ → CuSO₃ corresponds to the interaction of Cu(OH)₂ with

1)  H₂SO₃         2) SO₃ 3) Na₂SO₃       4) K₂SO₃

10.  In the reaction equation NO₂ + SO₂ → SO₃ + NO, the oxidant is

1)  NO₂             2) SO₂ 3) SO₃ 4) NO

11.  The reduced ionic equation Cu²⁺ + S^2- = CuS corresponds to the interaction

1)  copper sulphate and ammonium sulphide          3) copper carbonate and ammonium sulphide

2)  copper hydroxide and hydrogen sulphide          4) copper nitrate and hydrogen sulphide

12.  Alkines include a substance of composition

                1) С₆Н₆                           2) С₆Н₁₂                          3) С₆Н₁₄                          4) С₆Н₁₀

13.  Isomers are

16.  In the transformation scheme "C₂H₄ → X → CH₃CH₂OH" with the substance "X" is

           1) acetylene                     2) methanal                  3) chloroethane                  4) methanol

17.  The reaction product of butyne-1 with 1 mole of chlorine is

1)  2-chlorobutene-1    3) 1,1-dichlorobutane

2)  1,2-dichlorobutane                4) 1,2-dichlorobutene-1

18.  The organic product of the reaction C₂H₅OH + HBr → is

1)  ethane         2) bromoethane          3) ethenes       4) diethyl ether

19.  Type of chemical reaction of interaction of potassium hydroxide with hydrochloric acid                   1) compound reaction     3) substitution reaction

                       2) decomposition reaction                                          4) exchange reaction

20.  To increase the reaction speed 3 H₂ + N₂ = 2 NH₃ is necessary

1)reduce the concentration Н₂                      3) increase pressure

2)reduce the concentration N₂ 4) introduce an inhibitor 21. Neutral medium has an aqueous solution

1)  potassium chloride              3) ferric chloride (II)

2)  potassium carbonate            4) zinc sulfate

22.  The chemical equilibrium in the system CO_{2 (г)} + C _(тв) ↔ 2CO _(г) – Q will shift to the right if

1)   lower temperatures   3) increase the concentration of CO

2)   increase the concentration of CO₂             4) introduce a catalyst

23.  In 180 g of 15% sodium hydroxide solution, another 20 g of water was added. The mass fraction of the dissolved substance in the resulting solution is

1)   17,5%            2) 26,1%         3) 23,5%         4) 13,5%

24.  According to the thermochemical equation of glucose oxidation

С6Н12О6 (solid) +  6 О2(gas)  =  6 СО2  (gas)    + 6 Н2О (liquid)  + 2800 kJ upon oxidation of 0,05 mole of glucose

                      1) absorbed 200 kJ of heat                                     3) 200 kJ of heat is released

2)  140 kJ of heat is released         4) 280 kJ of heat is released

25. What is the mass in g of sodium carbonate required to interact with 20.8 barium chloride?

                  1) 106                               2) 53                              3) 10,6                            4) 0,106