Chemistry postgraduate entrance examination materials
General Chemistry Workbook
Chapter 1 Fundamentals of Chemical Thermodynamics
1. True or False Questions
1. The exothermic reaction is spontaneous. (F)
2. The ΔrHm of the reaction is the thermal effect of the reaction. (F)
3. Under given conditions, the heat generated by the reaction expressed by the following reaction equation is the same value. (F)
2H2(g) + O2(g) = 2H2O(l) and H2(g) +
O2(g) = H2O(l)
4. The ΔrSm of the reaction is positive and the reaction is spontaneous. (F)
5. If both ΔrHm and ΔrSm of the reaction are positive, ΔrGm decreases as the temperature rises. T)
6. Any process in which Gibbs free energy decreases must be a spontaneous process. (T)
7. The response ΔrSm to an increase in the number of molecules must be positive. (F)
8. The constant-pressure heat of a chemical reaction has nothing to do with the pathway, so it is a state function. (F)
9. The constant-pressure heat of a chemical reaction is not a state function, but is pathway-independent. (T)
10. At the specified temperature, ΔfHØm = 0 , ΔfGØm = 0 , SØm = 0 for the stable elemental substance. (F)
11. Applying Gaiss' law, not only the ΔrHm of the chemical reaction can be calculated, but also ΔrUm, ΔrGm, ΔrSm, etc. can be calculated. (T)
12. For the reaction of ΔrSØm>0, under the standard state, it is possible to react forward at high temperature. (T)
13. A reaction with ΔrGØm<0 must proceed spontaneously. (F)
14. Combustible substances contain heat, and vice versa do not contain heat. (F)
2. Multiple Choice Questions
1. Which of the following groups are state functions (A)
A．U、H、S、P、V、T
B． U、H、S、W、Q、G
C．ΔU、ΔH、ΔS、W、Q、ΔG
D．QP、QV、W、P、V、T
2. Among the following substances, ΔfGØm = 0 is (B)
A. Br2( g) B. Br2(l) C. Br2(aq) D. Br –(aq)
3. Which of the following statements is correct: (B)
A. The enthalpy of graphite is not zero
B. Under isothermal conditions, ΔrGmØ = ΔrHØm – TΔrSmØ
C. The greater the enthalpy change of the reaction, the greater the reaction rate.
D. In any case, as long as ΔS>0, the reaction must be a spontaneous reaction.
4. The substance with the smallest molar entropy is (C)
A. Br2(l) B. NaCl(s) C. Na(s) D. Cl2(g)
5. If the ΔrGmØ of a certain reaction = 10KJ . mol-1, it can be deduced that the reaction (C)
A. ΔrHmØ>0 ΔrSmØ<0 B. It must not be done spontaneously
C. Must not be spontaneous in the standard state
D. Must not be spontaneous in a non-standard state
6. At 373K, 101325Pa, during the process of water evaporation into water vapor, the variable of the thermodynamic content of the system is zero (B)
A．ΔrHØm B. ΔrGØm C. ΔrSmØ D. ΔrUm
7. Knowing that ΔfHØm of HCl = 431KJ . mol-1, the following reaction can be judged:
The ΔrHØm of H2(g) + Cl2(g) = 2HCl(g) is: (B)
A. –431KJ.mol-1 B. 862KJ.mol-1
C. –862KJ . mol-1 D. Unable to judge
8. The reaction expressing the standard molar enthalpy of formation of CO2 is (D)
A. CO(g) + 1/2O2(g) = CO2(g) ΔrHØm = －283.0KJ.mol-1
B. C(diamond) + O2(g) = CO2(g) ΔrHØm = -395.38KJ .mol -1
C. 2C(Graphite) + 2O2(g) = 2CO2(g) ΔrHØm = -787.0KJ .mol -1
D. C(graphite) + O2(g) = CO2(g) ΔrHØm = -393.5KJ .mol -1
9. According to regulations, the standard molar enthalpy of formation of the following substances is zero (C)
A. C (diamond) B. O3(g) C. Br2(l) D. I2(g)
10. Which of the following reactions is the reaction formula (D ) representing ΔfHØm (AgI,s)
A. Ag+(aq) + I-(aq) = AgI(s)
B. 2 Ag(s) + I2(s) = 2AgI(s)
C. 2 Ag(s) + I2(g) = 2AgI(s)
D. Ag(s) + 1/2I2(s) = AgI(s)
11. It is known that C (graphite) + O2(g) = CO2(g) ΔfHØm = -393.5KJ .mol -1 C (diamond) + O2(g) = CO2(g) ΔfHØm = -395.8KJ .mol -1
Then: C (Graphite)
ΔrHØm of C (diamond) is equal to (B)
A. –789.3KJ.mol-1 B. 2.3KJ.mol-1
C. –2.3KJ.mol-1 D. 789.3KJ.mol-1
12. At a certain temperature, which of the following reactions has the largest ΔrSØm value (B)
CaSO4(s) + 2H2O(l) = CaSO4.2H2O(s)
MgCO3(s) = MgO(s) + CO2(g)
C. 2SO2(g) + O2(g) = 2SO3(g)
D. H2(g) + Cl2(g) = 2HCl(g)
13. Reaction MgCl2(s) = Mg(s) + Cl2(g), ΔrHmΘ>0, under standard conditions, this reaction: (B)
A. Low temperature spontaneous B. High temperature spontaneous
C. Spontaneous at any temperature D. Spontaneous at any temperature
14. The decomposition reaction of ammonia: 2NH3(g) = N2(g) + 3H2(g), it is a spontaneous reaction at high temperature, and its reverse reaction is spontaneous at a lower temperature, which means that the ΔrHØm and ΔrSØm of the forward reaction are (A)
ΔrHØm > 0 ΔrSØm > 0
ΔrHØm > 0 ΔrSØm < 0
ΔrHØm < 0 ΔrSØm < 0
ΔrHØm < 0 ΔrSØm > 0
15. At 298.15K and standard state, the following reactions are all non-spontaneous reactions, and the one that is still non-spontaneous at high temperature is (D) (no need to calculate)
Ag2O(s) = 2Ag(s) + O2(g)
N2O4(g) = 2NO2(g)
Fe2O3(s) + C(s) = 2Fe(s) + CO2(g)
6C(s) + 6H2O(g) = C6H12O6(s)
16. If, at the thermodynamic temperature, the Gibbs free energy of a reaction changes to ΔG and the enthalpy to ΔH, then the entropy of the reaction becomes (B)
A、
B、
C、 T(ΔG-ΔH) D、T(ΔH-ΔG)
17. If ΔrGØm for a given reaction is known, all but one of the following can be determined (B)
A. In the standard state, the direction of the spontaneous response.
B. The equilibrium state at the same temperature.
C. The maximum useful work that can be produced under standard conditions.
D. To control this reaction, the use of a catalyst is ineffective.
18. CaO(s) + H2O(l) = Ca(OH)2(s) is a spontaneous reaction at 250C and 101KPa, and the reverse reaction is spontaneous at high temperature, which shows that the reaction: (A)
A. ΔrHmΘ<0 ΔrSmΘ<0 B. ΔrHmΘ>0 ΔrSmΘ >0
C. ΔrHmΘ<0 ΔrSmΘ>0 D. ΔrHmΘ>0 ΔrSmΘ<0
19. Under standard conditions, when H2(g) reacts with O2(g) to generate 2.0mol H2O(l), the exothermic Q KJ is exothermic, then the ΔfHØm value of H2O(l) is (B)
A. Q B. Q/2 C. Q/18 D. Q/36
20. Known reaction (1) MnO(s) + 1/2O2(g) = ΔrH1mØ of MnO2(s)
(2) MnO2(s) + Mn(s) = 2 MnO(s) 的ΔrH2mØ
Then ΔfHØm (MnO2, S) = (B)
A．ΔrH1mØ－ΔrH2mØ B. 2ΔrH1mØ+ΔrH2mØ
C. 2ΔrH1mØ－ΔrH2mØ D. ΔrH1mØ+2ΔrH2mØ
21. According to the data ΔfGØm(NO,g) = 86.5KJ .mol -1, ΔfGØm(NO2,g) = 51.3KJ .mol -1, reaction (1) N2(g) + O2(g) = 2NO(g) ; (2) 2NO(g) + O2(g) = 2NO2(g) , in the standard state, the correct one is (C)
A. (1) Can be spontaneous (2) Can’t B. Both (1) and (2) can be spontaneous
C. (2) Can be spontaneous (1) Can’t D. Neither (1) nor (2) can be spontaneous
22. Point out
Elemental substance equal to zero (D)
A, C (diamond) B, Fe(s)
C、O3(g) D、Br2(l)
23. Which of the following equations is correct according to Gaiss' law? B
A
△H3 C
△H1 △H5 △H4
B △H2 D
A、△H1+ △H2+△H3 =△H4
B、△H1+ △H2 = △H3 +△H4
C、（△H1+ △H2 ）－（△H3 +△H4）= △H5
D、△H1＋△H2＋△H3＋△H4 =△H5
24. At 298K, 101Kpa, the reaction
C(s) +
(g) = CO(g) △
2C(s) +
(g) =2 CO(g) △
Which of the following equations is correct? C
A、△
= △
B、△
= 2△
C、2△
= △
D、△
with △
irrelevant
25. It is known that the standard molar enthalpy of the reaction N2(g) + 3 H2(g) = 2NH3(g) becomes -92.22KJ·mol-1, which of the following data is the standard molar enthalpy of formation of NH3(g)? A
A、－46.11 KJ·mol－1 B、－92.22KJ·mol－1
C、46.11 KJ·mol－1 D、92.22KJ·mol－1
26. Which of the following symbols does not belong to the state function (C)
(1) T (2) P (3) U (4)
H (5) Q
A、(1) (4) (5) B、(1)(2) (4)(5)
C. (4)(5) D. None of them
27. At the same temperature without calculation, which of the following reactions has the largest difference between the heat of reaction at constant pressure and the heat of reaction at constant volume? (C)
A、C(s) + 1/2 O2(g) = CO(g)
B、C(s) + O2(g) = CO2(g)
C、2C(s) +3H2(g) =C2H6(g)
D, C (graphite) = C (diamond)
28. The entropy value of which of the following reactions (or processes) decreases (A)
A. NaCl crystals precipitate out of the solution
B. Reaction C(s) + 1/2 O2(g) = CO(g)
C, CuSO4 5H2O crystals dissolve in water
D. Sublimation of solid I2
29. Which of the following statements is correct (C)
A. Since ΔH=QP, Q is a state function
B. Under isobaric conditions, ΔH=QP
C. The process of constant pressure and only doing volume expansion work ΔH=QP
D. QP is always greater than QV
30. Under the conditions of 298K and 100Kpa, when N2 and H2 combine to form 1g NH3, the heat release is 27KJ, then the NH3
Yes (A)
A. – 46KJ•mol-1 B. – 46KJ
C. + 46KJ•mol-1 D. – 2.7KJ•g-1
31. The main component of natural gas is CH4, known CH4 (g), CO2 (g) and H2O (l)
They are –75, –394 and –286 respectively, then when 1m3 (273K, 101Kpa) CH4 is completely burned, it should release heat: ( C )
A. 2.7×104KJ B. 891KJ·mol-1
C. 3.98×104KJ D. Unable to calculate
32. It is known that N2(g)+3H2(g)=2NH3(g),
= –92.2KJ·mol-1, where mol-1 refers to (D)
A. per mol of NH3 B. per mol of H2
C. per mol of H2 D. per mol of the above reactions
33. The heat of combustion of graphite and diamond is 394 and 396KJ·mol-1 respectively, then the standard enthalpy of formation of diamond is (B )
A. –790 KJ·mol-1 B. 2KJ·mol-1
C. +790 KJ mol-1 D. –2 KJ mol-1
34. The following thermochemical equation is known
（1）C(g) + O2(g) = CO2(g)
= –394KJ·mol-1
（2）H2 (g) + 1/2O2(g) = H2O(l)
= –286KJ·mol-1
（3）C2H6(g) + 7/2O2(g) = 2CO2(g) +3H2O(l)
= –286KJ·mol-1
From this we can get the C2H6 (g)
equal to (A)
A. –1560KJ·mol-1 B. –86KJ·mol-1
C. +86 KJ·mol-1 D. Unable to calculate
35. Under the same temperature and pressure conditions, the correct ones are arranged according to the increasing order of entropy value (C)
A. H2O(l) H2O(g) H2O(s)
B. Cl2(l) Br2 (l) I2(s)
C. Na(s) NaCl(s) CaCl2(s)
D. O3(g) O2(g) O(g)
36. The melting point of benzene is 5.0ºC, and the heat of fusion is 10.7 KJ·mol-1, then the melting process ΔS of benzene is equal to (D)
A. 2.1 KJ·mol-1·K-1 B. 10.7KJ·mol-1
C. 38.5 KJ·mol-1·K-1 D. 38.5 J·mol-1·K-1
37. Known B2H6(g) and H2O(l)
are +31.4 KJ·mol-1 and –286 KJ·mol-1 respectively, and the combustion value of B2H6(g) is known to be –2153 KJ·mol-1, then the B2O3(g) can be obtained
for (B)
A. -1836 KJ·mol-1 B.-1264 KJ·mol-1
C. +2153 KJ mol-1 D.+1264 KJ mol-1
3. Fill in the blanks
1. The system has done 200J of work on the environment, and the system must absorb _____ heat_200_____ J from the environment in order to increase the thermodynamic energy of the system by 50J.
2. Known reaction 4NH3(g) + 5O2(g) = 4NO(g) + 6H2O(l)
ΔrHØm = －1170KJ.mol-1
4NH3(g) + 3O2(g) = 2N2(g) + 6H2O(l)
ΔrHØm = －1530KJ.mol-1
Then the standard molar enthalpy of formation ΔfHØm of NO(g) is_______
3. At 373K and 101.325Kpa, the process of liquid H2O turning into water vapor
ΔrHØm____=_______；ΔrHØm____>_____；ΔrSØm_>_____(塑>0 =0 <0)
4. The ΔrHØm of the reaction 2N2(g) + O2(g) = 2N2O(g) at 298K = 164.0KJ . mol-1, then the ΔrUØm of this reaction is 164_________KJ . mol-1
5. At 298K and 101.325Kpa, the following reactions are known
C(s) + H2O(g) = CO(g) + H2(g)
ΔfHØm/KJ . mol-1 －241.8 －110.5
ΔfGØm /KJ.mol-1 －228.6 －137.2
Then ΔrSØm is __________J . mol-1 . K-1
6. If a reaction is exothermic and the entropy change of the reaction is less than zero, the reaction can be spontaneous at __low temperature________, but not spontaneous at _high temperature_________.
7. The ΔrHØm,298 of N2(g) + 3H2(g) = 2NH3(g) = -92.2KJ .mol -1, if the temperature rises, the ΔrHØm, T____ will not change much____________; ΔrSØm,T_ Little change _____________; ΔrGØm,T__ increase_______ (qualitative answer required)
8. The chemical reaction A(g) + B(g) = 2C(g), A, B, and C are all ideal gases. Under the standard state of 250C, the process is completed in two different ways: (1) No work , exothermic 40KJ; (2) do the maximum work, exothermic 2KJ. Then in the two cases of (1) and (2), ΔHØ is __-40________, -40________; ΔGØ is ___-38_____, -38_______;
ΔSØ are -6.7_______, __-6.7______, respectively.
4. Calculation questions
1. Using the ΔrGØm of the following reactions, calculate the Gibbs free energy ΔfGØm of the standard molar formation of Fe3O4(s) at 298K.
(1) 2Fe(s) + 3/2O2(g) = Fe2O3(s) ΔrGØm = －742KJ.mol-1
(2) 4 Fe2O3(s) + Fe(s) = 3 Fe3O4(s) ΔrGØm = －78 KJ.mol-1
2. Set the following reaction
(1) A + B = C + D ΔrHØm = －40 KJ.mol-1
(2) C +D = E ΔrHØm = 60 KJ.mol-1
What is the ΔrHØm of the following reactions?
C + D = A + B
2C + 2D = 2A + 2B
A + B = E
3. Whether it is possible to eliminate the pollutant CO of automobile exhaust by thermal analysis method, known thermal decomposition reaction:
CO(g) = C(graphite) + O2(g)
ΔfHØm /(KJ . mol-1) －110.53 0 0
SYM/(J . mol-1 . K-1) 197.56 5.74 205.03
4. It is known that SØ = 32.6 J . mol-1 . K-1, ΔHcØ = -297.19KJ . mol-1 for monoclinic sulfur, and SØ = 31.8 J . mol-1 . K-1, ΔHcØ = for orthorhombic sulfur -296.90KJ .mol -1; Orthogonal sulfur transforms into monoclinic sulfur at 101Kpa and 95.50C. The calculation shows which crystal form of sulfur is stable at the pressure and temperature of 250C and 95.50C respectively.
5. There is iodine in the iodine tungsten lamp tube, which can generate tungsten iodide from the tungsten deposited on the wall after the filament evaporates: W(s) + I2(g) = WI2(g), WI2(g) contacts high temperature The tungsten obtained by decomposing is deposited on the filament, so the filament of the iodine-tungsten lamp has a long service life and can be used for high power. Under the standard state, what is the minimum temperature of the filament to decompose WI2(g)?
When 298K is known: W(s) I2(g) WI2(g)
ΔfHØm /(KJ . mol-1) 0 62.24 －8.37
Nail/(J . mol-1 . K-1) 33.5 260 250.4
Chapter 2 Principles of Chemical Equilibrium
1. True or False Questions
1. The unit of chemical reaction quotient Q and standard equilibrium constant is 1. (T)
2. After the reaction reaches equilibrium, the concentration of each reactant and product is constant. (F)
3. Reaction CO2 + H2
The KØ of CO + H2O at 673K and 873K are 0.080 and 0.41 respectively, and this reaction is exothermic. (F)
4. When the reversible reaction reaches equilibrium, the rate of the forward reaction is equal to the rate of the reverse reaction. (T)
5. The catalyst does not affect the chemical balance. (T)
6. For the reaction of ΔrHØm<0, the higher the temperature, the smaller the KØ, so the larger the ΔrGØm. (F)
7. At a certain temperature, the relationship between the standard molar Gibbs free energies of the 1 and 2 reactions is ΔrGm1Ø = 2ΔrGm2Ø, and the relationship between the standard equilibrium constants of the two reactions is K2Ø = (K1Ø)2. f
8. For any reversible reaction, after the equilibrium is reached, the temperature is raised, and the equilibrium moves to the endothermic direction. (T )
For an exothermic reaction, lower the temperature and the equilibrium shifts to the opposite reaction. (T )
9. For the reaction in which the number of gas molecules does not change before and after the reaction, changing the pressure has no effect on the equilibrium. (T )
2. Multiple Choice Questions
1. The KØ of a certain reaction A(g) + B(g) = G(g) + H(g) = 10－12, which means: D )
The initial concentrations of reactants A and B are too low.
The positive reaction cannot proceed and the products do not exist.
The reaction is reversible, and the chances of going in both directions are equal.
A positive reaction can proceed but not to a great extent.
2. At a certain temperature, the standard equilibrium constant of a reaction (B )
A. Constantly B. Determined by the equation
C. Changes with equilibrium concentration D. Changes with equilibrium pressure
3. Reaction C(s) + H2O(g) = CO(g) + H2(g) ΔrHm>0, the following statement is correct (B)
This reaction is an endothermic reaction. As the temperature increases, the rate of the forward reaction increases and the rate of the reverse reaction decreases, so the equilibrium shifts to the right.
Increasing the pressure is not conducive to the conversion of H2O(g).
Increasing the temperature causes KØ to decrease.
Adding a catalyst can increase the output per unit time.
4. Given a reversible reaction, when the temperature rises from T1 to T2, the equilibrium constant KØ2 > KØ1, then ( A ) of the reaction
ΔrHm>0 B. ΔrHm<0 C. ΔrHm=0 D. Unable to judge
5. Suppose the reversible reaction A(g) + 2B(g) = C(g) + D(g), ΔrHmØ>0. The condition for A and B to obtain the highest conversion rate is (B )
A. High temperature, low pressure B. High temperature, high pressure
C. Low temperature, low pressure D. Low temperature, high pressure
6. Reaction NO2(g) = NO(g) + KØ of 1/2O2(g) = a, then the reaction:
The KØ\ of 2NO2(g) = 2NO(g ) + O2(g ) should be (C )
A. a B. 1/a C. a2 D.
7. The condition for establishing chemical equilibrium is (C)
A. The system undergoes a reversible reaction.
B. Under constant temperature and constant pressure conditions, the reversible reaction of the system.
C. A reversible reaction in a closed system under constant temperature conditions.
D. No conditions are required.
8. In the description of chemical equilibrium movement, the correct one is (C)
A. When the reversible reaction reaches equilibrium, increase the product concentration, and the equilibrium will move forward.
B. When the reversible reaction reaches equilibrium, increase the total pressure of the system, and the equilibrium will move forward
C. At a certain temperature, when a reversible reaction reaches equilibrium, increase the temperature, and the equilibrium will move to the endothermic direction
D. At a certain temperature, when a reversible reaction reaches equilibrium, increase the temperature, and the equilibrium will move toward exothermic direction
9. Factors affecting chemical equilibrium constants (D)
A．Concentration of reactants B. Catalyst
C. Product concentration D. Temperature
10. The relationship between the equilibrium constants of the forward reaction and the reverse reaction is (B)
A. The two are equal B. The two are reciprocal
C. The sum of the two is equal to 1 D. The quotient of the two is equal to 1
11. Know the equilibrium constants for the following reactions:
H2(g) + S(s) = H2S(g) K1Ø
S(s) + O2(g) = SO2(g) K2Ø
Then the standard equilibrium constant A of the reaction H2(g) + SO2(g) = O2(g) + H2S(g)
A. K1Ø/ K2Ø B. K2Ø/ K1Ø
C.K1Ø K2Ø D.K1Ø－ K2Ø
12. It is known that the equilibrium constants of the first three reactions below are KØ1, KØ2 and KØ3 respectively
(1) N2(g) + O2(g) = 2NO(g)
(2) H2(g) + 1/2 O2(g) = H2O(g)
(3) 2NH3(g) + 5/2 O2(g) = 2 NO(g) + 3 H2O(g)
(4) N2(g) + 3 H2(g) = 2NH3(g)
Then the KØ4 of the fourth reaction is (D)
A. KØ1+ 3KØ2 -KØ3 B. KØ1KØ2 KØ3
C. KØ1KØ2 /KØ3 D. KØ1KØ32 /KØ3
13. In the reversible reaction A + B = C + D, there are only A and B at the beginning, and after a long period of reaction at a certain temperature, the final result is (C)
A．The concentration of C and D is greater than that of A and B B. The concentration of A and B is greater than that of C and D
C．The concentrations of A, B, C, and D no longer change
D. A, B, C, D molecules no longer react
14. At 5000C, in a 1-liter airtight container, start the reaction with 1mol N2, 3mol H2 and 2mol NH3. (KØ of the reaction at this time = 0.08), then at equilibrium: B
A, N2, H2 and NH3. The ratio of the amount of substance is 1:3:2
B. The ratio of the amount of N2 and H2 substances is 1:3
The amount of C, N2 substance is 1
D. The total amount of matter is 6
15. Decomposition reaction of PCl5: PCl5(g) = PCl3(g) + Cl2(g), 48.5% decomposes when reaching equilibrium at 2000C, and 97% decomposes when reaching equilibrium at 3000C. Which of the following statements is correct (B)
A．The reaction is exothermic B. The reaction is endothermic
C. Raising the temperature, the equilibrium shifts in the opposite direction
D. Changes in pressure have no effect on equilibrium
16. The reaction PCl5(g) = PCl3(g) + Cl2(g), the total pressure at equilibrium is PØ (Pa), and the dissociation rate is 50%. Then the KØ at this time is (C)
A． 1 B. 1/2 C. 1/3 D. 1/4
17. The gas reaction A(g) + B(g) = C(g), establishes a chemical equilibrium in a closed container, if the temperature remains the same, but the volume is reduced by 2/3, then the equilibrium constant KØ is the original (D )
A．3 times B. 9 times C. 2 times D. unchanged
18. By changing which of the following situations, any reaction that has reached equilibrium can increase its product (A)
A. Increase the concentration of reactants B. Increase the temperature
C. Increase pressure D. Decrease temperature
19. The ΔrHØm of reaction 2A(g) + B(g) = 2C(g) >0, the following statement is correct ( D )
A. According to the expression of KØ, as the reaction proceeds, the concentration of C increases continuously, and the concentrations of A and B decrease continuously, so KØ increases continuously.
The forward reaction is an endothermic reaction. As the temperature rises, the rate of the forward reaction increases, while the rate of the reverse reaction decreases, and the equilibrium shifts to the right.
Increase the pressure, so that both c(A) and c(B) increase, and the balance does not move.
Adding a catalyst can only shorten the time to reach equilibrium, without changing the equilibrium constant.
20. At 250C, the ΔrHØm of N2(g) + 3 H2(g) = 2NH3(g) = -92 KJ . mol-1, when the reaction reaches equilibrium in a closed container, if a certain amount of neon gas is added, there will be (C)
The balance shifts to the right and ammonia production increases.
The balance shifts to the left and ammonia production decreases.
The state of equilibrium remains unchanged.
The positive reaction rate is accelerated.
21. When synthesizing nitric acid, the reaction in the absorption tower is:
3NO2(g) + H2O(l) = 2HNO3(aq) + NO(g) ΔrHØm = -2001 KJ . mol-1, in order to increase the equilibrium yield of HNO3, it is necessary to ( A )
A. Pressurize and cool down B. Pressurize and heat up
C. Reduce pressure and increase temperature D. Reduce pressure and reduce temperature
22. According to ln(KØ2 /KØ1) =
, under what conditions, lowering the temperature equilibrium shifts to the direction of positive reaction (B)
A. ΔrHmØ>0 B. ΔrHmØ<0
C. ΔrSmØ<0 D. Low temperature zone
23. Baking soda (NaHCO3) is decomposed according to the following formula to produce soda ash (Na2CO3)
2NaHCO3(s) = Na2CO3(s) + CO2(g) + H2O(g)
Known at 273K,
=0.23, at 323K,
=3.9×10-4, then the above reaction (A)
A. <0 B. （323K）<0
C. >0 D. Negative value
24. The chemical formula of lactic acid is represented by HLac. A known
HLac + H2O = H3O+ + Lac- =1.4×10-4
H2O + H2O = H3O+ + OH-
=1.0×10-14
Then the K0 value of the reaction Lac-1 + H2O = HLac + OH-1 is (C)
A.
+
B.
-
C.
/
D.
·
25. Known: (1) CaC2O4= Ca2+ + C2O42- K0=2.3×10-9
(2) Hac = H+ + Ac- K0=1.8×10-5
(3) HC2O4-= H+ + C2O42- K0=6.4×10-5
Then the K0 of the reaction CaC2O4 + Hac = Ca2+ + HC2O4- + Ac- can be calculated, and then it can be judged that calcium oxalate, one of the components of gallstones, is in acetic acid (C)
A. Soluble B. Slightly soluble
C. Insoluble D. Oxidation-reduction reaction occurs
3. Fill in the blanks
1. At 673K, the KØ of N2(g) + 3 H2(g) = 2NH3(g) = 0.62, and the KØ of NH3(g) = 1/2 N2(g) + 3/2 H2(g) = _________.
2. The expression of the standard equilibrium constant for the reaction Fe(s) + 2H+(aq) = Fe2+(aq) + H2(g) is KØ = ____________________.
3. Know the ΔrGØm and KØ of the following reactions at the specified temperature,
(1) N2(g) + 1/2O2(g) = N2O(g) ΔrGØm1, KØ1
(2) N2O4(g) = 2NO2(g) ΔrGØm2, KØ2
(3) 1/2N2(g) + O2(g) = NO2(g) ΔrGØm3, KØ3
Then the reaction 2 N2O(g) + 3 O2(g) = 2N2O4(g) ΔrGØm = ______, KØ =____________
4. It is known that ΔfHØm(NO,g) = 90.25 KJ . mol-1, at 2273K, the KØ of the reaction N2(g) + O2(g) = 2NO(g) = 0.100, at 2273K, if P(N2 ) = P(O2) = 10Kpa, P(NO)=20Kpa, the reaction quotient Q = _______, the reaction proceeds in the direction of ______; at 2000K, if P(NO) = P(N2) =10 Kpa , P( O2) = 100Kpa, the reaction quotient Q = ______, the reaction proceeds in the direction of __________.
5. PCl5(g) = PCl3(g) + Cl2(g), under certain T and P, if the volume of a certain amount of PCl5 gas is 1 liter, then 50% of PCl5 gas has been decomposed into PCl3 and Cl2. If the pressure is reduced so that the volume becomes 2 liters, the decomposition rate of PCl5 will be _____. If the pressure is kept constant and helium is added to make the volume 2, then the decomposition rate of PCl5 will be __________. (fill ``increase Big'', ``Decreased'', ``Unchanged'')
6. Reversible reaction. 2Cl2 (g) + 2H2O(g) = 4HCl(g) + O2(g) ΔrHØm > 0 , after the reaction reaches equilibrium, perform the following operations to discuss the impact:
(1) Increase the volume of the container, n(H2O,g)________________________;
(2) Add O2, n(H2O,g)____________; n(HCl,g)______________-
(3) Reduce the volume of the container, n(Cl2,g)____________; P(Cl2,g)_____________; KØ=_____________.
(4), add rare gas, keep the volume constant, n(HCl,g)________________;
Keep the pressure constant, n(HCl,g)__________;
(5) Add catalyst, n(HCl,g)________________.
4. Calculation questions
1. (1) Write down the standard equilibrium constant expression of the reaction O2 (g) ==O2(aq), it is known that at 200C , p(O2)=101Kpa, the solubility of oxygen in water is 1.38 × 10-3 mol·l -1 Calculate the KØ of the above reaction at 20oC, and calculate the C(O2) in water in equilibrium with the 101Kpa atmosphere at 200C (P(O2) in the atmosphere=21.0 Kpa)
(2). Known hemoglobin (Hb) oxidation reaction Hb(aq) + O2(g)=HbO2(aq) at 200C KØ = 85.5, calculate KØ(293K).Hb(aq) + O2(g) for the following reaction ) = HbO2(aq)
2. At 383K, the ΔrGØm of the reaction Ag2CO3(s) = Ag2O(s) + CO2(g) = 14.8 KJ . mol-1, find the KØ(383K) of this reaction; when drying Ag2CO3(s) at 383K, to prevent It is decomposed by heat, what is the minimum Kpa of P(CO2) in the air?
3. Reaction C(s) + CO2(g) = 2CO(g) KØ= 2.10×103 at 12270C, KØ = 1.6×102 at 10000c; find:
(1) Is the reaction exothermic or endothermic?
(2) What is the ΔrHmØ of the reaction?
(3) What is ΔrGmØ at 12270C?
(4) Calculate the ΔrSmØ of the reaction.
Chapter 3 Chemical Reaction Rate
1. Judgment of right and wrong
1. The rate equation of the reaction H2(g) + I2(g) = 2HI(g) is ν= kc(H2) . c(I2), then the reaction is an elementary reaction. (F)
2. When the concentration of the reactant doubles, the reaction rate also doubles, so the reaction must be a first-order reaction. (T)
3. The unit of the rate constant k of the zero-order reaction is S-1. (F)
4. In the speed equation, when the exponents of the concentrations of various substances are equal to the coefficients in the reaction equation, the reaction must be an elementary reaction. (F)
5. For the same chemical reaction, when the conditions are changed, the activation energy decreases and the reaction speed also decreases F
6. For a reaction that is endothermic in the forward direction, if the temperature is raised, the speed of the forward reaction will inevitably increase, and the speed of the reverse reaction will decrease. (F)
7. The energy possessed by activated molecules is called activation energy. (T)
8. The activation energies of forward and reverse reactions are equal in value but opposite in sign. (F)
9. When the temperature is increased, the increase of the reaction rate is greater for a reaction with a larger activation energy than for a reaction with a small activation energy. (T)
10. There are reactions Ⅰ and Ⅱ. At 298K, the reaction rate νI > νII, while at 318K
νI < νII, 则 EaI > EaII (F )
2. Multiple Choice Questions
1. For a certain decomposition reaction, when the reactant concentration is 0.2mol . l-1, the reaction rate is 0.3 mol . l-1 . S -1 . -1, the reaction rate (mol . l-1 . S-1) of this reaction will be (D)
A．0.30 B. 0.60 C. 0.90 D. 2.70
2. The main reason why the reaction speed increases with the increase of temperature is: (D)
A. The number of molecular collisions increases at high temperature.
B. The energy of molecules increases at high temperature, so that the energy of each collision increases.
C. The number of activated molecules decreases with increasing temperature.
D. The percentage of activated molecules increases with the increase of temperature.
3. The reaction A + B → C is an elementary reaction, and the unit of the rate constant of this reaction should be (D )
A. mol . l-1 . S-1 B. S -1 C.L. S-1 D. mol-1 . L. _ S-1
4. It is known that the following reaction 2A + B → C is an elementary reaction, then the relationship between νA and νB is (B)
A. νA =νB B. 1/2νA=νB
C. 2νA=νB D. ν2A =νB
5. Under the given conditions, the reaction 2NO + 2H2 = N2 + 2H2O is carried out in two steps,
I. 2NO + H2 = N2 + H2O2 (chronic)
II. H2O2 + H2 = 2H2O (fast)
If the volume of the container is reduced to half of the original, the reaction rate becomes ( ) times the original? A. 2 B. 4 C. 8 D. 16
6. For the reaction aA + Bb = product, if C(A) is kept unchanged and C(B) is doubled, the reaction rate is increased to 4 times. If C(B) is kept constant, C(A) is doubled, and the reaction rate is doubled, then the reaction order ( )
A．3 B. 2 C. 4 D. 1
7. For zero-order reactions, which of the following statements is correct ( )
A．The activation energy is very low B. The reaction rate is independent of the reactant concentration
C．The concentration of reactants is independent of time
D．The reaction rate constant is 0
8. Which of the following statements about catalysts is wrong ( )
A. Among several reactions, selectively speed up the reaction rate of one of them.
B. It can inhibit the progress of certain reactions.
C. The equilibrium constant of the chemical reaction can be changed, but the thermal effect is not affected.
D. It is possible to change the ratio of the forward and reverse reaction rates of a certain reaction.
9. The reaction rate of reaction 2SO2(g) + O2(g) → 2SO3(g) can be expressed as ν= －
, can also be expressed as ( )
A.
B. －
C. －
D. －
10. Which of the following statements is correct ( )
A. A non-elementary reaction is composed of several elementary reactions.
B. Where the index of each substance concentration in the rate equation is equal to the stoichiometric coefficient of each reactant in the reaction equation, this reaction is an elementary reaction.
C. The reaction order is equal to the sum of the stoichiometric coefficients of the reactants in the chemical reaction formula.
D. The reaction rate is proportional to the product of the reactant concentration
11. There is a chemical reaction A + B → D, the data of the three experiments are as follows:
Initial (A)∕mol.l-1 Initial (B)∕mol.l-1 Initial rate of formation of D (mol.l-1.S_1)
0.03 0.03 0.3 × 10-4
0.06 0.06 1.2 × 10-4
0.06 0.09 2.7 × 10-4
The rate equation for this reaction is ( )
A. ν = kc(A)c(B) B. ν= kc2(B)
C. ν = kc(A)c2(B) D. ν = kc2(A)
12. The unit of the rate constant of a certain chemical reaction is mol.l-1.S_1, and the series of the chemical reaction is ( )
A. 2 B. 1 C. 0 D. 3
13. The rate equation of the reaction A(g) + B(g) → C(g) is ν = kc2(A) c(B), if the closed reaction volume is doubled, the reaction rate is the original ( ) times
A. 1/6 times B. 1/8 times C. 8 times D. 1/4 times
14. The reaction mechanism of the known reaction 2NO(g) + 2H2(g) = N2(g) + 2H2O(g) is:
(1) NO + NO == N2O2 (comfortable)
(2) N2O2 + H2 == N2O + H2O (slow)
(3) N2O + H2 == N2 + H2O (fast)
Then the overall reaction rate equation is:
A. ν = kc2(NO)c2(H2) B. ν = kc(NO)c(H2)
C. ν = kc2(NO)c(H2) D. ν = kc2(NO)
15. The activation energy of a certain reaction is 26KJ . mol-1, the activation energy of its reverse reaction is ( )
A. －26KJ. mol-1 B. >26KJ. mol-1
C. <26KJ . mol-1 D. Unsure
16. At 250C, the reaction N2(g) + 3 H2(g) = 2NH3(g) ΔrHØm = -922 KJ . mol-1, if the temperature is raised, then ( )
A. The rate of the reaction decreases and the rate of the reverse reaction increases.
B. As the rate of the reaction decreases, the rate of the reverse reaction also decreases.
C. The rate of the forward reaction increases and the rate of the reverse reaction decreases.
D. As the rate of the forward reaction increases, the rate of the reverse reaction also increases.
17. For a chemical reaction, which of the following cases has a greater rate? ( )
A. The larger the activation energy. B. The more negative the ΔrHØm
C. The smaller the activation energy is. D. The more negative ΔrGØm is
18. The activation energy of the forward reaction (Ea positive) is greater than the activation energy of the reverse reaction (Ea reverse), then the standard molar enthalpy change of the forward reaction ( )
A. ΔrHØm > 0 B. ΔrHØm = (Ea positive - Ea negative)/2
C. ΔrHØm < 0 D. Not sure
19. Factors that do not affect the reaction rate constant k ( )
A. Reaction temperature B. Change in reactant concentration
C. Activation energy of reaction D. Catalyst
20. As shown in the figure, the relative enthalpy involved in the reaction A + B → C + D is: activated complex > A + B > C + D, therefore: ( )
A. The reaction is irreversible.
B. There is no catalyst for this reaction.
C. The reaction is exothermic.
D. The activation energy of the reverse reaction is lower than the activation energy of the forward reaction.
21. A certain reaction A + B is known
C+D
is +5.0L·mol－1·S－1, the reaction
Which of the following matches?
A、－5.0L·mol－1·S－1 B、＜5.0L·mol－1·S－1
C. >5.0L·mol－1·S－1 D. Unsure
22. Known reaction 2 A(g) + B(g)
ΔrHØm<0 for 2 C(g). Which of the following statements is correct ( )
A. Because of K
=
, as the reaction proceeds, p(C) increases gradually, p(A), p(B) decrease gradually, and the equilibrium constant increases gradually.
B. to raise the temperature,
increase,
A decrease will cause the balance to shift to the left.
C. Adding a catalyst can accelerate the rate of the forward and reverse reactions to the same extent, and accelerate to reach equilibrium.
D. Increase the pressure to increase p(A) and p(B),
Increase and the balance shifts to the left.
23. For a certain chemical reaction, which of the following changes will occur as the reaction proceeds ( )
A. The reaction rate decreases. B. The rate constant decreases.
C. The equilibrium constant becomes smaller D. The activation energy decreases
24. The experiment found that the reaction: 2NO(g) + Cl2= 2NOCl is the second-order reaction of NO and the first-order reaction of Cl2. Which of the following reaction mechanisms is possible ( )
A、 NO + NO + Cl2 =2 NOCl
B. Cl2 = 2 Cl (slow)
NO + Cl = NOCl (comfortable)
C, Cl2 = 2 Cl (fast)
NO + Cl = NOCl (chronic)
D、2 NO= N2O2 (快)
Cl2 + N2O2 = 2NOCl (slow)
25. Enzyme-catalyzed reactions are mostly 0-order reactions. Regarding 0-order reactions, the following statements are correct ( )
A. The mechanism is simple and is an elementary reaction
B. There is a linear relationship between the concentration of reactants and the reaction time
C. The concentration of reactants is inversely proportional to the reaction time
D. The reaction rate is inversely proportional to the reaction time
26. For the reaction A + B 3D, the activation energies of forward and reverse reactions are m KJ·mol-1 and n KJ·mol-1 respectively, then the reaction
for( )
A. m-n B. n-m C.m-3n D. 3n-m
27. Fresh milk deteriorates in 4 hours at 300K, but it is stored at 277K for 48 hours, then the activation energy of milk is ( )
A. Unable to calculate B. +5.75 KJ·mol-1
C.-74.5 KJ mol-1 D. +74.5 KJ mol-1
28. The activation energy of the reaction at 503K is 184.1 KJ·mol-1. If the catalyst is added, it becomes 10416 KJ·mol-1. At this time, the multiple of the positive reaction rate increase is ( )
A. 1×104 B.1×106
C.1×108 D. 1×102
29 It is known that k=0.35 min-1 (304K) of the first-order reaction 2N2O5 4NO2(g) + O2(g), at this temperature the initial concentration of N2O5 changes from 0.16 mol·L-1 to 0.02 mol·L- 1 hour ( )
A.150s B. 356s
C.594s D. 2.5s
30 The chemical reaction rate should be expressed as ( )
A. The amount of change in the concentration of the reactant per unit time
B. The amount of change in product concentration per unit time
C. Positive value of change in reactant concentration
D. The positive value of the change in the concentration of the substance
31. The rate expression of reaction 2NO + O2 = 2NO2 ( )
A. +dC(NO2) /dt B. -dC(NO2) /dt
C. -2dC(NO2) /dt D. Neither is correct
32 Which of the following statements is correct ( )
A. For the reaction with larger Ea, k must be larger
B. At a certain temperature, k does not change with temperature
C. k does not vary with temperature
D. k value has nothing to do with the addition of catalyst
33. Which of the following expressions is incorrect ( )
A. V+ usually decreases with time
B. K is a characteristic constant of a chemical reaction at a certain temperature
C. The temperature is constant, the greater the concentration, the greater v
D. The initial concentration is different, v is different, but the equilibrium concentration is the same
34. CO + NO CO2 + 1/2 N2 exothermic reaction, if the temperature rises by 10ºC, then ( )
A. Increase the rate constant by a factor of 10
B. Double the equilibrium constant
C. Decrease the equilibrium constant
D. to decrease the reaction rate
35. Which of the following statements about the reaction series is correct ( )
A. Determined according to the chemical reaction equation
B. Determined by experiment
C. The same number of molecules as the reaction
D. Determined according to the reaction mechanism
36. It is known that the decomposition of H2O2 is a first-order reaction. If the concentration is reduced from 1.0mol·dm-3 to 0.6mol·dm-3, it takes 20 minutes, and the concentration is reduced from 0.60mol·dm-3 to 0.36mol·dm-3. The time is ( )
A. More than 20 minutes
B. Equal to 20 minutes
C. less than 20 minutes
D. can't judge
37. For reactions >0, the use of positive catalysts can
A. to increase the reaction rate
B. Decrease the reaction rate
C. Increase conversion rate
D. Has no effect on conversion rate
38. The reaction of gas on the solid surface is generally ( )
A. Level zero B, level one C, level two D, level three
3. Fill in the blanks
1. For a 0-order reaction, the shape of the reactant concentration C versus time t curve is: ________
2. Reaction N2(g) + 3 H2(g) = 2NH3(g), if –dC(N2)/dt = 2.0 mol . l -1 . S-1, then –dC(H2)/dt = _____mol . l-1 . S-1, –dC(NH3)/dt = ____________mol . l-1 . S-1
3. The step-by-step reaction of complex reaction 3ClO- == ClO3- + 2Cl- is as follows:
(1) 2ClO- == ClO2- + Cl- (slow reaction)
(2) ClO2- + ClO- == ClO3- + Cl- (fast reaction)
Write the velocity equation for the above complex reaction: _____________________________
4. The speed of a certain reaction determines step 2A(g) + B(g) == 3C(g), mix 1 mol A(g) and 2 mol B(g), the reaction occurs immediately, when half of AB is used When , the reaction speed is ___________-times of the initial speed of the reaction; when 2/3 of AB is used up, the reaction speed is ______________ times of the initial speed.
5. The activation energy of a reaction is 85 KJ · mol-1, then the reaction rate at 400.15K is ______________ times that at 300.15K.
6. If within a certain temperature range, if the temperature rises by 100C, the reaction rate doubles, then the reaction rate at 550C is _________ times that at 250C; the reaction rate at 1000C is ___________________ at 250C _ times.
7. There are two reactions I and II. The activation energy of reaction I is EaI which is greater than the activation energy EaII of reaction II. As the temperature rises, the reaction speed of reaction I increases ______________________.
8. Reaction 2AB(g) = A2(g) + B2(g), the activation energy of forward reaction Ea(+) = 44.3 KJ mol -1, ΔfHØm of AB = 1.35 KJ mol -1, the activation energy of reverse reaction Should be:_______________.
9. The reaction rate equation of reaction Aa + Bb → dD ν = kcx(A)cy(B) If the unit of k is L2 . mol -2 . S-1 , then x+y=_________.
4. Calculation questions
At 660K, the reaction 2NO(g) + O2(g) == 2NO2(g), the initial concentrations of NO and O2 C(NO) and C(O2) and the experimental data of - dC(NO)/dt at the beginning of the reaction are as follows :
C（NO）/mol . l-1 C（O2）/mol . l-1 - dC(NO)/dt /mol . l-1 . S-1
0.10 0.10 3.0x10-2
0.10 0.20 6.0x10-2
0.30 0.20 0.54
(1) Write the rate equation for the reaction.
(2) Find the reaction order and the rate constant at 660K.
(3) When T=660K, c(NO)=c(O2)=0.15 mol . l-1, what is the reaction rate?
2. The reaction rate constants at 200C and 300C are 1.3 x 10-5 mol-1 . L . S-1 and 3.5 x10-5 mol-1 . L . S-1 respectively. According to the Vant Hoff rule, calculate the rate constant at 500C Reaction rate constant.
3. In the reaction of H2(g) + I2(g) → 2HI(g), the reaction rate constant k1=4.45x10-5 mol-1 . L . S -1 at 556K, k2=6.43x10-2 at 700K mol- 1.L.S - 1 .
Find out: (1) What order is this reaction?
(2) The activation energy Ea of the reaction
4. The experiment confirmed that the mechanism of the reaction 2NO(g)+2H2(g)=N2(g)+2H2O(g) is: 2NO(g)+H2(g)=N2(g)+H2O2(g) slow
H2O2(g)+ H2(g)= 2H2O(g) fast
(1) Write down the rate equation of the reaction;
(2) Determine the order of the reaction;
(3) When c(NO)=3.00×10－3mol·L－1, c(H2)=6.00×10－3mol·L－1
The reaction rate is 4.30×10-3mol·L-1·S-1, calculate the reaction rate
Chapter 5 Acid-base reaction
multiple choice
1. The pH of 0.10mol . l-1 weak acid solution is__________
A．Less than 1 B. Greater than 1 C. Equal to 1 D. Not sure
2. Among the 0.01 mol . l-1 HAC solution, the smallest concentration is __________
A. HAC B. H+ C. AC- D. OH-
3. Among the following solutions (concentrations are all 0.10mol . l-1), the one with the largest degree of dissociation is _________
A. HAC B. HAC (contains NaAC)
C. HCN D. HCOOH
4. Among the following solutions, the one with the highest pH is_________
A. 0.10mol.l-1 HCl B. 0.10mol.l-1H2S
C. 0.10mol.l-1 NH3.H2O D. 0.10mol.l-1NH4AC
5. Which of the following statements is incorrect is __________
Use NaOH to neutralize HAC and HCl solutions with the same pH and equal volumes,
The amount of NaOH needed is equal.
Use HCl solution with the same pH and equal volume of Ba(OH)2 and
NaOH solution requires an equal amount of HCl.
Use NaOH to neutralize the substance with the same concentration and volume of HAC and
HCl solution requires an equal amount of NaOH.
Use HCl to neutralize KOH and NH3 with the same concentration and volume
The same amount of HCl is required for the aqueous solution.
6. 1 mol . l-1 NaOH solution than 1 mol . l-1 NH3 water________
A. Contains more OH- B. Contains less H+
C. High concentration of H+ D. Small concentration of H+
7. When the 0.10mol . l-1 HAC solution is diluted with water to twice the original volume, its H+ concentration and
The change trend of PH is __________
A. increase and decrease B. decrease and increase
C. To half the original size and increase D. To double the original size and decrease
8. After equal volumes of aqueous solutions of two strong acids with a pH of 1.0 and a pH of 3.0 are mixed, the
PH value is___
A. 1.0 B. 1.5 C 2.0 D. 1.3
9. Knowing that PH=4.55 of 0.010mol . l-1 a certain weak acid, it can be deduced that the acid Ka is _______
A. 5.8 x 10-2 B. 9.8 x 10-3
C. 7.8 x 10-8 D. 8.6 x 10-7
10. In H2S aqueous solution, the most particles are (except H2O molecules)___________
A. H+ B. S2- C. HS- D. H2S
11. After mixing equal volumes of NaOH and HAC solutions with the same amount and concentration of substances, the mixed solution
The relationship that exists between the amount and concentration of substances related to ions is ________
A、C(Na+) >C(AC-) > C(OH-) > C(H+)
B、C(Na+) >C(AC-) > C(H+) > C(OH-)
C、C(Na+) + C(H+)>C(AC-) + C(OH-)
D、C(Na+) >C(OH-)>C(AC-) + C(H+)
12. Which of the following statements is incorrect is _________
A. For weak acid solutions, the smaller the concentration, the greater the degree of ionization and the greater the concentration of hydrogen ions;
B. In the dilute solution of polybasic weak acid, the concentration of its acid group is approximately equal to that of the last stage
Dissociation equilibrium constant.
C. For a weak alkaline solution, when diluted with water, the pH value decreases.
D. For weak electrolyte solutions, the same ion effect reduces the degree of ionization, and the salt effect increases the degree of ionization
13. In the 0.10mol . l-1 HAC solution containing 0.10mol . l-1 HCl, the expression is correct
is _______
A. C(H+)=C(AC-) B. C(H+)<C(AC-)
C.. C(H+)>>C(AC-) D. None of the above answers are correct
14. The Ka1 of 0.10mol . l-1 a dibasic weak acid H2A is 4.0 x 10-7 and the Ka2 is 8.0×
10-10, then the A- ion concentration of the solution is about ________ (mol . l-1)
A. 1.0 x 10-4 B 2.0 x 10-4 C. 8.0 x 10-10 D. 4.0 x 10-10
15. Mix 1 liter of 4 mol . l-1 ammonia water with 1 liter of 2 mol . l-1 hydrochloric acid solution, after mixing, OH-
The ion concentration is—————(mol . l-1)
A. 1 B. 2 C. 8.0 x 10-4 D. 1.79 x 10-5
16. The strength of a weak acid is mainly related to which data it is in aqueous solution________
A. Concentration B. Degree of dissociation C. Dissociation constant D. Solubility
17. According to the principle of equilibrium movement, in 0.10mol . l-1 HAC solution, which of the following statements is incorrect
A. When concentrated HAC is added, the equilibrium shifts to the right due to the increase in the reactant concentration,
As a result, the dissociation degree of HAC increased.
B. Adding a small amount of NaOH solution will shift the equilibrium to the right.
C. Diluting with water increases the degree of dissociation.
D. Adding a small amount of HCl solution will reduce the degree of dissociation of HAC.
18. Which of the following statements is correct ______
A. The degree of dissociation of a strong electrolyte indicates that the electrolyte dissociates in solution
degree of size.
B. The electrolyte is completely dissociated in the solution, so the degree of dissociation is 100%
C. In a hydrochloric acid solution with a concentration of 1 x 10-9 mol . l-1, the pH is 7
D. Neutralize an equal volume of HCl and HAC solutions with the same pH, the required
The amount of NaOH is the same.
19. Adding some NH4Cl crystals to 1 liter of 0.10mol . l-1 NH3 aqueous solution will make ___
A. The dissociation constant Kb of NH3 water increases.
B. The dissociation constant Kb of NH3 water decreases
C) The pH of the solution increases.
D) The pH of the solution decreases.
20. Add some water to 1 liter of 0.10mol . l-1 HAc aqueous solution, at this time
A. The degree of dissociation of HAc decreases B. The degree of dissociation of HAc increases.
C. The pH of the solution decreases D. The concentration of H+ ions in the solution remains the same.
21. Generally used as a buffer solution is _________
A. A solution of a salt of a weak acid and a weak base
B. Mixed solution of weak acid (or weak base) and its salt
C. A solution whose pH never changes
D. A solution of strong acid (or strong base) and its salt.
22. The pH value of the buffer solution is mainly determined by which of the following factors————
A. Equilibrium constant of the conjugated pair B. Concentration ratio of the conjugated pair
C. The temperature of the solution D. The total concentration of both conjugated pairs
23. Among the following solutions, the one with the largest buffering capacity is_______
A. 0.10mol . l-1 NH3 water 0.1 liter
B. 0.10mol . l-1 NH4Cl water 0.1 liter
C, 0.10mol . l-1 NH3 water 0.5 liters and 0.10mol . l-1 NH4Cl water 0.05 liters
the mixture of
D, 0.20mol . l-1 NH3 water 0.5 liters and 0.20mol . l-1 NH4Cl water 0.05 liters
the mixture of
24. Mix 0.025mol . l-1 HAC solution with an equal volume of NaAC solution to keep the pH
4.05, the concentration ratio of acid and salt after mixing should be—————
A. 6 : 1 B. 50 : 1 C. 30 : 1 D. 5 : 1
25. The pH range of the buffer solution prepared with HSO3-[K(HSO3-) = 3 .0 x 10-8] and SO32-__
A. 10~12 B. 6.5~8.5 C. 2.4~4.0 D. 2~4
26. The pH values of the following salt solutions of the same concentration, from small to large, are:
NaA, NaB, NaC, NaD (ABC D are all weak acid radicals), then the acid with the highest dissociation degree of each corresponding acid at the same concentration and temperature is _______
A. HA B. HB C. HC D. HD
27. Drop two drops of phenolphthalein solution into the Na2CO3 solution, the solution is pink, after slightly heating, the color of the solution____
A. Darken B. Unchanged C. Lighten D. Disappear
28. When preparing SnCl2 solution in the laboratory, it must be prepared in a small amount of hydrochloric acid, and then diluted to the required
Concentration, to get a clear solution, this is due to _______
A. Formation of a buffer solution B. Common ion effect
C. The salt effect promotes the dissolution of SnCl2 D. Inhibits the hydrolysis of SnCl2
29. According to the acid-base proton theory, which of the following statements is incorrect is ________
A. The direction of acid-base reaction is that a strong acid reacts with a strong base to form a weak acid and a weak base.
B. There is no concept of salt in the compound.
C) The stronger the acid, the stronger its conjugate base.
D. The dissociation reaction in aqueous solution, the hydrolysis reaction and the neutralization reaction are all protons
transfer reaction.
30. Among the following substances, the one that can act as both an acid and a base is ________
A. PO43- B. NH4+ C. H3O+ D. HCO3-
31. Which of the following is not a conjugate acid-base pair ( )
A、NH4+, NH3 B、HF, H2F+
C、NH3，NH2－ D、H+3O,OH－
32. For the following responses, the correct statement is ______
[Al(H2O)6]3+ + H2O → [Al(H2O)5(OH)]2+ + H3O+
A. [Al(H2O)6]3+ is a base, and H2O is its conjugate acid.
B. [Al(H2O)6]3+ is a base, and [Al(H2O)5(OH)]2+ is its conjugate acid.
C, [Al(H2O)6]3+ is an acid, and H2O is its conjugate base
D. [Al(H2O)6]3+ is an acid, and [Al(H2O)5(OH)]2+ is its conjugate base.
33. The order of the conjugate basicity of H2O, H2AC+, NH4+ is ________
A. OH- > NH2- >AC- B. NH2- > OH- > AC-
C. OH- > NH3 >HAC D. HAC>NH3 >OH-
34. The K value of the reaction Zn2+ + H2O = ZnOH+ + H+ is 2.5 x 10-10, then 0.10mol . l-1
The pH of the solution is ______
A. 3.25 B. 5.30 C. 4.34 D. 6.78
35. If the acid-base reaction HA + B- = HB + A- K = 10-4, the following statement is correct _______
A. HB is a stronger acid than HA B. HA is a stronger acid than HB
C. HA and HB have the same acidity D. The strength of the acid cannot be compared
36. Three salt solutions of 0.10mol . l-1: (1) NH4Cl. (2) NaCN (3) NH4CN
The order of the pH of the various salt solutions from large to small is————
A. (1) > (2) > (3) B. (2) > (1) > (3)
C. (2) > (3) > (1) D.(1) > (3) > (2)
37. Add NaOH solution dropwise to 0.10mol . l-1H3PO4 solution until pH=8.0, the phosphoric acid form with the highest concentration in the solution is _____________ (PKa1=2.0, PKa2=7.2, PKa3=12.6 of H3PO4)
A、H3PO4 B、H2PO4－ C、HPO42－ D、PO43－
38. In 110ml of HAC with a concentration of 0.10mol . l-1, add 10ml of HAC with a concentration of 0.10
mol . l-1 NaOH solution, then the pH value of the mixed solution is _______
(PKa=4.75 of known HAC)
A. 4.75 B. 3.75 C. 2.75 D.5.75
39. At 250C, the ionization degree of 0.1 mol . l-1 a weak acid solution is 0.2%, then the OH- concentration of this solution is _______ mol . l-1
A. 2 × 10-4 B. 1 × 10-10 C. 5 × 10-5 D. 5 ×10-11
.40, according to the following proton transfer reaction:
(1) HS- + H2O = S2- + H3O+ K1=1 x 10-12
(2) CN- + H3O+ = H2O + HCN K2=1 x 10-4
(3) HAC + H2O = H3O+ + AC- K3=1 x 10-5
(4) HNO2 + CN- = HCN +NO2- K4=1 x 10-6
The strongest protic base is _________
A. NO2- B. AC- C. CN- D. S2-
41. According to the acid-base proton theory, all of the following substances are acidic ______
A、H2S、 C2O42- 、 HCO3-
B、HPO42- 、 NH4+、 [Fe(H2O)6]3+
C、Na(S)、BF3、H2O
D、NH4+、CO32－、H2O
42. It is known that at 298015K, the equilibrium constants of the following reactions:
HCN = H+ +CN- Ka=4.93 x 10-10
NH3 + H2O = NH4+ +OH- Kb=1.79 x 10-5
H2O = H+ + OH- Kw=1.00x 10-14
The equilibrium constant for the following reactions is ________
NH3 + HCN = NH4+ + CN-
A. 8.82 x 10-29 B. 2.75 x 10-19 C. 8.82 x 10-1
43. Among the following compounds, the pH value of its aqueous solution is the highest ________
A. NaCl B. Na2CO3 C. NH4Cl D. NaHCO3
44. In the saturated aqueous solution of H2S, which of the following concentration relations is correct————
A. [S2-]≈2[H+] B. [HS-]≈[H+]
C. [H2S]≈[H+]+[HS-] D. [H2S]≈[S2-]
45. Adding some NaAC to the HAC solution will make—————
A. The Ka of HAC decreases B. The degree of ionization of HAC decreases
C. The H+ ion concentration of HAC increases D. The pH value of the solution decreases
46. 0.10mol . l-1HAC solution in 1 liter of 0.10mol . l-1NaAC aqueous solution, the electricity of HAC
The distance is——————
A. 10Ka% B. 1000Ka% C. 100Ka% D. 100√Ka/0.1%
47. The concentration of hydrogen ions in weakly acidic aqueous solution can be expressed as _______
A. 14_POH B. KW/POH C. 10-POH D. 10-(14-POH)
48．3.2% formic acid in 0.20mol . l-1 formic acid solution has been ionized, and its ionization constant is——
A.2.1 x 10-4 B. 1.25 x 10-6 C. 4.8 x 10-5 D.2.1 x 10-8
49. If the dissociation constant of acetic acid is 1.75 x 10-5 mol . l-1, what ratio is mixed with acetic acid and sodium acetate to obtain a buffer solution with pH=6.2______
A. 6.3/17.5 B. 6.3/1.75 C. 6.3/35 D. 63/1.75
50. Pass H2S to saturation in 0.30 mol . l-1 HCl solution, which of the following is the S2-concentration?
(In saturated H2S solution, the concentration of H2S is 0.10mol L-1)
A、0.10 mol . l-1 B、0.30 mol . l-1
C、Ka10·Ka20 D、1.1×10－19 mol . l-1
fill in the blank
1. Among NH4+, Cl-, AC-, H2O and other substances, the substance that is both proton acid and proton base is ________, its conjugate acid is ____________________, and its conjugate base is ________________.
2. The buffer pair substance in the buffer solution composed of NaH2PO4 and Na2HPO4 is ________________________________. The effective range of pH value of the buffering effect of the buffer solution is _________________________.
3. According to the acid-base proton theory, the conjugate base of [Al(H2O)5(OH)]2+ is _______________, and its conjugate acid is ____________________.
4. The pH of 0.10mol . l-1 NaHCO3 solution = ________________,
PH of 0.10mol . l-1 Na2CO3 solution = _____________________
(PKa1 = 6.4, PKa2 = 10.2 for H2CO3).
5. When preparing a buffer solution, the principle of choosing a buffer pair is ____________________________.
6. It is known that [H+]=1.3 x 10-3 mol . l-1 of 0.10mol . l-1 HAC, then the ionization degree of HAC is _________, and the ionization equilibrium constant is ____________________ .
7. In H2S saturated solution, [S2-] is approximately equal to _________________.
8. It is known that PKa1 = 2.1, PKa2 = 7.2, PKa3 = 12.6 of H3PO4, prepared with phosphate
For the buffer solution, if Na2HPO4 is used as the acid, a buffer solution with a pH in the range of ________________ can be prepared; if Na2HPO4 is used as a base, a buffer solution with a pH in the range of ____________________ can be prepared.
9. Add 60ml 0.20mol . l- 1NaOH to 50ml 0.12mol . l-1 H3PO4 solution
solution, then the pH of the mixed solution = ______________________. Add 50ml0.20mol . l-1 HCl solution to 60ml 0.10mol . l-1 Na3PO4 solution, then the pH of the mixed solution = __________________.
10. The relationship between degree of dissociation α, dissociation constant K and concentration C is: ________________ varies with concentration
C changes, but ________ does not change with the concentration of C. The mathematical expression of the law of dilution is __________.
11. To double the degree of dissociation of 0.1 liter of 4.0 mol . l-1 NH3 water, add water____
______Lift.
12. In the H2S solution of 0.10 mol . l-1, the concentration of H+ is 9.5 x 10-5 mol . l-1 , PH =_______, the concentration of HS- ions is _____________mol . l-1, the concentration of S2- ions is ________mol . l-1.
13. To neutralize the same volume of NaOH and NH3 aqueous solutions with the same pH, the required amount of HCl solution is _____________; to neutralize the equal volume of HCl and HAC solutions with the same concentration, the required amount of NaOH is __________________. (Fill equal or not equal)
14. For the following solutions with a pH of 3.0, after washing with an equal volume of water, the pH of the HAC solution is _________; the pH of the HCl solution is _____________; the pH of the HAC-NaAC solution is ____________.
15. Add 0.01 mol solid NaAc to 0.1 liter of 0.10 mol . l-1 HAC solution (assuming the volume remains constant), then the concentration of H+ ions in the solution will be __________; the pH will be ____________, and the concentration of AC- ions will be _________ (fill in increase, decrease or remain unchanged). The mixed solution is called __________ solution, and its H+ ion concentration is ______ mol . l-1. After adding a small amount of acid, alkali or water to the solution, the pH of the solution is ____.
16. The relationship between the graded hydrolysis constant Kn1 of CO32-, Kn2 and the graded dissociation constants Ka1 and Ka2 of H2CO3 solution is Kn1 = ______________, Kn2 =_____.
17. According to the proton theory, NH4+, PO43+, HCO3-, S2-, H3PO4 and AC- ions are proton acids ________, and their conjugate bases are _______; proton bases are ____________, and their conjugate acids are respectively It is ______________________; among them, __________________________ is both an acid and a base.
3. Calculation questions
1. Calculate the pH value of 0.20 mol . l-1 Na2CO3 aqueous solution. If an equal volume of 0.20mol . l-1HCl is added to the solution , calculate the pH value of the mixture
(Ka1=4.3 x 10-7, Ka2=5.6x 10-11 for H2CO3).
2. To prepare a buffer solution with pH = 8.25, ask how many milliliters of 0.50 mol . l-1 HCl is added to 200ml of 0.20 mol . l-1 NH3H2O?
(Known PKb of NH3.H2O = 4.75).
3. Mix 10ml, 0.30 mol . l-1 of HCOONa with 20ml, 0.15 mol . l-1 of HF. Calculate the equilibrium constant of the reaction and [HCOO-], [F-] and [H+] in the solution as How many?
(KHCOOH = 1.7 x 10-4, KHF = 6.8 x 10-4).
4. It is known that the pH value of a 0.10 mol . l-1 aqueous solution of a certain weak acid at 298K is 3.0,
Find: (1) Ka (2) α (3) Ka, α, and PH value after doubling the dilution
(4) The pH value of the mixed solution obtained after mixing equal volumes with 0.10 mol . l-1 NaOH solution (5) The pH value of the mixed solution obtained after mixing equal volumes with 0.20 mol . l-1 NaOH solution.
Chapter 6 Precipitation-Dissolution Reaction
1. Multiple choice questions
1. Which of the following statements is correct————
The product of the concentration of insoluble electrolyte ions is the solubility product of the substance.
The larger the solubility product, the larger the solubility.
When the ion product of the insoluble electrolyte in the solution is greater than its solubility product, it will
produce precipitation.
When the solution containing AgCl solid is diluted with water, the solubility product of AgCl remains unchanged and its solubility increases.
2. The expression of the solubility product KØSP of Sr3(PO4)2 is________
A. KØSP = [Sr2+][PO43-] B. KØSP = [3Sr2+][2PO43-]
C.KØSP = [Sr2+]3[PO43-]2 D. KØSP = [Sr32+][(PO4)23-]
3. Among the following saturated solutions of insoluble silver salts, the concentration of Ag+ ions is the largest (solubility product in brackets)________
A. AgCl (1.8 x 10-10) B. Ag2C2O4 (3.4 x 10-11)
C. AgCrO4 (1.1 x 10-12) D. AgBr (5.2 x 10-13)
4. Among the following saturated solutions, the one with the smallest SO42- ion concentration (solubility product in brackets)________
A. BaSO4 (1.1 x 10-10) B. CaSO4(9.1 x 10-6)
C. PbSO4 (1.6 x 10-8) D. Ag2SO4 (1.4 x 10-5)
5. The KØSP of Hg2Cl2 is 1.3 x 10-18 , and the concentration of 0.1 liter of saturated solution is _____________mol.L-1
A. 6.88 x 10-7 B. 1.68 x 10-4
C. 6.88 x 10-8 D. 1.14 x 10-9
6. The solubility product of BaSO4 is 1.0 x 10-10 , and its relative molecular mass is 233.3. If 1.0 x 10-3 mol of BaSO4 is put into 10 liters of water, the undissolved sample has______
A. 0.21g B. 2.1g C. 2.1 x 10-2g D. 2.1 x 10-3g
7. The saturated solution concentration of CaF2 is 2.0 x 10-4 mol.L-1, and its solubility product is _______
A. 2.6 x 10-9 B. 3.2x 10-11 C. 4.0 x 10-8 D. 8.0 x 10-10
8. The mass of solute in 1 liter of Ag2C2O4 saturated solution is 0.06257 grams, if the factors such as the hydrolysis of ions after dissolution are not considered, the KØSP of Ag2C2O4 is __________
A、4.24 x 10-8 B. 2.36 x 10-10 C. 3.50 x 10-11 D. 8.74 x 10-12
9. The solubility product of AgBr KØSP = 5.2 x 10-13, the solubility of AgBr in 0.1 mol.L-1 KBr solution is _________ mol.L-1
A.2.6 x 10-6 B. 5.2 x 10-12 C. 4.0 x 10-13 D. 4.0 x 10-14
10. Compared with the solubility of CaF2 in 0.1 mol.L-1 KNO3 solution and water, which one of the following ________
A. Increased B. Decreased C. Same D. Unable to judge
11. Which of the following statements is correct __________
In a solution containing multiple ions, the one that can form a precipitate with a small solubility product must precipitate first.
A precipitate with a large solubility product will be transformed into a precipitate with a small solubility product.
The complete precipitation of an ion means that it has completely become a precipitate.
When the ion product of the insoluble electrolyte in the solution is less than its solubility product, the insoluble electrolyte will dissolve.
12. It is known that the solubility products of PbCl2, PbI2 and PbS are 1.6×10-5, 7.1×10-9 and 8.0×10-28 respectively. To see white PbCl2, yellow PbI2 and black PbS precipitates in sequence, the order of adding reagents to the Pb2+ solution is _____________
A、Cl－、I－、S2－ B、S2－、Cl－、I－
C、I－、Cl－、S2－ D、S2－、I－、Cl－
13. When Mg(OH)2 solid establishes equilibrium in water
Mg(OH)2 = Mg2+ + 2 OH-
In order to reduce the amount of Mg(OH)2 solids, it is necessary to add a small amount of ________
A. Na2S B. MgSO4 C. NH4NO3 D. NaOH
14. A certain solution contains KCl, KBr and K2CrO4, the concentration is 0.010 mol.L-1
When 0.1 mol.L-1AgNO3 solution is added dropwise to the solution, the first and last precipitate is—————
A. AgBr and Ag2Cr2O4 B. Ag2CrO4 and AgCl
C. AgCl and AgBr D. AgCl and Ag2CrO4
15. In a mixed solution containing Cl-, Br-, I-, and CrO42- ions at a concentration of 0.012 mol.L-1, gradually add AgNO3 solution to cause precipitation of the ions, and the order of precipitation is _________ (already It is known that the solubility products of AgCl, AgBr, AgI and Ag2CrO4 are 1.8 × 10-10, 5.0 × 10-13, 8.3 × 10-17, 1.2 × 10-12)
AgCl、AgBr、AgI、Ag2CrO4
B. Ag2CrO4 、AgI、 AgBr、AgCl
C. Ag2CrO4、AgBr、AgI、AgCl
D. AgI,、AgBr、AgCl,、Ag2CrO4
16. Dissolve the following substances in water at the same temperature to form a saturated solution. The most soluble is ____
A. AgCl (KØSP = 1.8 x 10-10) B. Ag2CrO4(KØSP = 1.1 x 10-12)
C.Mg(OH)2(KØSP = 1.8 x 10-11) D.FePO4(KØSP = 1.3 x 10-22)
17. Drop H2S into 0.05 mol.L-1CuCl2 solution until saturated [H2S] = 0.1 mol.L-1, the remaining [Cu2+] in the solution is equal to ________ mol.L-1
A. 3.6 x 10-16 B. 6.3 x 10-18
C. 2.5 x 10-17 D. 6.3 x 10-19
(KØSP known, CuS = 6.3 x 10-36 K total H2S = 1.0 x 10-19 )
18. There is a poorly soluble electrolyte A2B, its solubility is S, then KØSP is ________
A. S3 B. 4S2 C. 2S3 D. 4S3
19. It is known that the KØSP of AgCl and Ag2CrO4 are 1.8 × 10-10 and 1.1 × 10-12 respectively. If [Cl-] = [CrO42-] = 10-5 mol.L-1 in a certain mixed solution, when Ag+ is added to reach 10-4mol.L-1, _______ will occur
A. AgCl precipitates first B. Only AgCl precipitates
C. Only Ag2CrO4 precipitates D. Both precipitate
20. [CaF2] = 2.0 × 10-4 mol.L-1 in the saturated solution of CaF2, where KØSP must be
________
A. 6.0 ×10-2 B. 4.0 ×10-8 C. 3.2 × 10-11 D. 8.0 × 10-12
2. Fill in the blanks
1. If the KØSP of CaC2O4 is 2.6 × 10-9, the required oxalate ion concentration is _______________mol.L-1 to make a solution containing 0.02mol calcium ion concentration per liter precipitate.
2. The solubility of PbI2 in water is 1.2 × 10-3 mol.L-1, its KØSP = _____________,
PbI2 is dissolved in 0.01 mol.L-1KI solution, and its solubility is ____________ mol.L-1.
3. In the mixed solution containing Cl-, Br-, I-, and CrO42- ions at a concentration of 0.012 mol.L-1, gradually add AgNO3 solution to precipitate the ions, and the order of precipitation is ________________________________________________
(It is known that the solubility products of AgCl, AgBr, AgI, and Ag2CrO4 are 1.8 × 10-10, 5.0 × 10-13, 8.3 × 10-17, 1.2 × 10-12, respectively.)
4. The expressions of the solubility product constants of the following insoluble electrolytes are
KØSP (BaS) =_______________, . KØSP (PbCl2) =_________________ . KØSP (Ag2CrO4) =________________.
5. The solubility product of AgCl is equal to 1.2 × 10-10, and the Ag+ ion concentration (mol.L-1) at which AgCl precipitation begins to form from a solution with a Cl- ion concentration of 6.0 × 10-3mol.L-1 is ______________ .
6. Add HCl to the silver salt solution to precipitate AgCl until the concentration of chloride ions in the solution is 0.20 mol.L-1. Theoretically, the concentration of silver ions at this time is ______________________________________________
(known KØSP (AgCl) =1.56 × 10-10).
7. Infuse H2S gas into 0.05 mol.L-1 CuCl2 solution to saturation, then the pH of the solution = __________. (Ka1 of H2S = 9.1 × 10-8, Ka2 = 1.1 × 10-12, . KØSP ( CuS) = 6.3 × 10-36).
8. The three factors that affect the order of step-by-step precipitation are ___________, ______________, __________________.
3. Calculation questions
1. There is 0.1 mol of MnS precipitated today, what concentration of HAC should be used in 1 liter to dissolve it? (Known: KSP(MnS) =2.5 × 10-10 KHAC = 1.8 × 10-5 Ka1(H2S) = 1.32 × 10-7, Ka2(H2S) = 7.10 × 10-15 ）
2. Mix equal volumes of 0.02 mol.L-1Ba2+ solution and 0.2 mol.L-1 HF solution, and then adjust the pH of the mixture to 1.0 (the volume of the solution does not change when adjusting the pH value)
(1) Explain whether BaF2 precipitation can be generated through calculation.
(2) Find the pH range that can form BaF2 precipitation without forming Ba(OH)2.
( KSP(BaF2) = 1.0 × 10-6, KSP(Ba(OH)2) = 5.0 × 10-3,
Ka(HF) = 3.5 × 10-4).
3. Add an equal volume of 0.1mol.L-1 chlorine water to the 0.50mol.L-1MgCl2 solution, and ask whether Mg(OH)2 precipitation can be formed? If NH4Cl is added to this 0.1mol.L-1 ammonia solution (s), so that the concentration of NH4Cl is 0.020mol.L-1, can Mg(OH)2 be precipitated? If so, how much solid NH4Cl should be added per liter of 0.1mol.L-1 ammonia water So that Mg(OH)2 does not precipitate? (The volume change of the solution after adding solid is negligible) (Known: KSP(Mg(OH)2 = 1.2 × 10-11, Kb(NH3.H2O) = 1.79 × 10-5, MNH4Cl = 53.5)
4. When the CaF2 solid is dissolved in a buffer solution of pH = 3.5 (without F-) to reach equilibrium, [Ca2+] = 1.0 x 10-3 mol.L-1 is measured (assuming that there is no CaF+ ion in the solution), find KSP of CaF2. (known: Ka(HF) = 1.8 x 10-5)
5. Calculate the grams of AgBr that can be dissolved in 100ml of 1.0 mol.L-1 ammonia water.
Chapter 7 Atomic Structure
True or False:
Electrons have wave-particle duality, so each electron is both a particle and a wave. (F)
The wave nature of electrons is the result of statistical regularities exhibited by the motion of a large number of electrons. (T)
The wave function ψ is the amplitude of the electron wave. (F)
4. The wave function ψ, that is, the atomic orbit, is a mathematical function formula describing the state of electron space movement. (T)
5. In the schematic diagram of the electron cloud, the density of the small black dots indicates the probability density of electrons appearing. (T)
6. For multi-electron atoms, the atomic orbital energy is jointly determined by n , l , m. (F)
7. Both electron cloud and atomic orbital angle distribution diagrams have positive and negative points. (F)
8. |ψ|2 represents the probability of electrons. (F)
9. The first ionization energy I of elements in the same main group decreases gradually from top to bottom. (T)
10. The atomic orbital of P is approximately in the shape of "8", so the P electrons move in the shape of "8". (F)
2. Multiple choice questions:
1. One of the experiments based on the layered arrangement of electrons outside the nucleus (D)
Famous experiments proving that electrons have volatility ( B )
Rutherford's experiment to demonstrate that an atom has a positively charged nucleus (A)
Experiments Proving that Electrons Are Particles (C)
A. Scattering experiment of alpha particles B. Electron diffraction
C. Cathode rays can push the blades to rotate or do work
D. Atomic Spectroscopy
2. Describe the order of the energy level of the electron layer and the distance between the electron cloud and the nucleus (D)
The secondary factor that describes the shape of atomic orbitals and determines the energy levels of electrons in multi-electron atoms is (B)
The direction that describes the stretching direction of the electron cloud or atomic orbital in space is (C)
What describes the electron spin state outside the nucleus is (A)
A. Spin quantum number B. Angle quantum number
C. Magnetic quantum number D. Principal quantum number
3. Bohr's theory has successfully analyzed the spectrum of hydrogen atoms. If the energy of the hydrogen atom's extranuclear electrons when it moves on the fourth orbit is 2.04 × 10-18J higher than its energy when it moves on the first orbit, then the extranuclear electrons When electrons jump from the fourth orbit to the first orbit, the frequency of the emitted electromagnetic wave is ( D )
A、6.14×10－15S-1 B、1.23×1016 S-1
C、3.68×1016 S-1 D、3.08×1015S-1
4. Which of the following atoms has an atomic orbital energy independent of the angular quantum number (C)
A．Li B. Ne C. H D. F
5. The energy required for the 1S electrons of neon atoms to be excited to the 4S and 4P orbitals respectively (C)
A．The former is greater than the latter B. As much
C. The former is smaller than the latter D. Unable to judge
6. Six sets of quantum numbers of the following electrons (3, 2, 2, +1/2); (3, 0, 1, +1/2);
(2、-1、0、+1/2); (1、0、0、0); (3、2、2、2);
Among (2, 0, -2, +1/2), the one that cannot exist is ( C )
A. 2 sets B. 3 sets C. 5 sets D. 6 sets
7. For a multi-electron atom, among the electrons described below, the electron with the highest energy is (D)
A、 （2、1、1、-1/2） B、 （2、1、0、-1/2）
C、 （3、1、1、-1/2） D、 （3、2、2、-1/2）
8. When the quantum number n=3 and l=1, the maximum number of electrons that can be accommodated (A)
A、 6 B、 2 C、 8 D、 16
9. A 2p electron can be described as one of the following six groups of quantum numbers
（1） 2、1、0、+1/2 （2）2、1、0、-1/2
（3） 2、1、1、+1/2 （4）2、1、1、-1/2
（5） 2、1、-1、+1/2 （6）2、1、-1、-1/2
Try to point out the correct combination of four electrons in 2P4 in the electron layer structure of oxygen atom (C)
A、（1）（2）（3）（4） B、（1）（2）（5）（6）
C、（2）（4）（5）（6） D、（3）（4）（5）（6）
10. To estimate the total effect of an electron being shielded, the repulsion of electrons in which of the following situations should generally be considered (D)
A. Inner electrons to outer electrons B. Outer electrons to inner electrons
C.
D, the same layer and the inner layer electrons to a certain electron
11. Which of the following statements about atomic orbitals is correct (B)
A) Atomic orbitals are the trajectories of electrons
B. An atomic orbital is a state of spatial motion of electrons, namely the wave function
C. Atomic orbitals represent the probability of electrons appearing at various points in space
D. Atomic orbitals represent the probability density of electrons appearing at each point in space
12. Which of the following statements is correct (C)
A. |Ψ|2 represents the probability of an electron
B. The spatial image of |Ψ|2 is the atomic orbital
C. The visualized image of |Ψ|2 distribution in space is called electron cloud
D. |Ψ|2 value is greater than Ψ value
13. If the electronic configuration outside the nucleus of an atom is written as ns2np7, it violates (A)
A. Poly exclusion principle B. Minimum energy principle
C. Hund's rule D. A special case of Hund's rule
14. The electronic layer structure and element name of element 24 is (B)
A, [Ar]3d44s2 Chromium (Cr)
B, [Ar]3d54s1 Chromium (Cr)
C, [Ar]3d44s2 vanadium (V)
D. [Ar]3d54s2 vanadium (V)
15. Among the following elements, the one with the smallest first ionization energy is ( B )
A、Li B、Na C、FD、Cl
16. Among the following elements, the one with the highest first ionization energy is (D)
A、Be B、 B C、C D、N
17. Now there is an element with 5 semi-filled d-orbital electrons in its atom, the element is (A)
A、Cr B、 Co C、 Fe D、 Zn
18. The ground state atom of an element has 2 electrons in the n=5 orbital, and there will be (C) electrons in the n=4 orbital of the atom
A, 8 B, 18 C, 8-18 D, 8-23
19. The element whose valence electron configuration is 3d84s2 belongs to (C)
A, ds region, third cycle, group IIB
B, d block, third cycle, group VI
C, d block, fourth cycle, group VIII
D. ds zone, fourth cycle, group IB
20. Element E can usually form E2O oxide, so element E may be located in the periodic table
Which races? (B)
A, I or VI B, I or VII
C, II or VI D, II or VII
21. Which of the following is the correct sequence of increasing ionization energy of element atoms (D)
A、 1S2, 1S22S22P2, 1S22S22P6, 1S22S22P63S1
B、 1S22S22P63S1, 1S22S22P6, 1S22S22P2, 1S2
C、 1S2, 1S22S22P6, 1S22S22P2, 1S22S22P63S1,
D、 1S22S22P63S1, 1S22S22P2, 1S22S22P6, 1S2
22. The element with the greatest electronegativity, the element with the greatest first electron affinity, and the element with the greatest first ionization energy are (C)
A、F F F B、Cl Cl F
C、F Cl F D、F F Cl
23. The lowest n value that allows f orbitals to exist is ( B )
A、 2 B、4 C、5 D、 6
24. It takes about the same energy to remove an electron from a neutral Li, Be, B atom, but it is much larger when removing the second electron ( A )
A. Li B, Be C, BD, the same
25．When the angular quantum number is 5, the possible degenerate orbitals are (C)
A. 6 B. 9 C、11 D. 13
26. Regarding the shielding constant σ, which of the following statements is wrong ( D )
A. The greater the number of shielded electrons, the greater the value of σ
B. The farther the shielded electron is from the nucleus, the larger the value of σ
C. The shielding constant σ of an electron reflects the effect of the electron shielding the nucleus
D. When n and z are the same, the greater the σ value of an electron, the lower the energy of the electron
27. Regarding ionization energy, which of the following statements is correct (A)
A. The smaller the ionization energy I1, the stronger the metallicity of the element
B. I1 of group IIIA elements in the third period is greater than I1 of IIA elements
C. The difference between I2 and I1 of Li is smaller than the difference between I2 and I1 of Be
D. The I1 of N is smaller than the I1 of C and O
28．It is predicted that the number of elements in the ninth period of the periodic table is (C )
A、72 B、68 C、 50 D、32
3. Fill in the blanks
1. The state of motion of electrons outside the nucleus can be described by the quantum number ——————————————, and the electron energy level outside the nucleus of a multi-electron atom is related to ——————————— related.
2. Among the electronic configurations 1s22s22p44s1, 1s22s2, 1s22s22p1, 1s22s22p63s13d1, 1s22s12p12d13s1, 1s22p2, 1s22s22p13d1, the ground state of the atom is __________________________; the excited state of the atom is It is _______________, and the wrong one is __________________________________________________________.
3. Microscopic particles such as electrons are different from macroscopic objects in two characteristics: quantization of physical quantities and wave-particle duality, which can be proved by ____________________________ and ______________________________________ facts respectively.
4. In the electron diffraction experiment, the smaller the diameter of the hole, the more the spatial coordinate of the particle is ____________ the diffraction angle________, that is, the more the ________ of the particle——————————, so in classical mechanics, it is described by _____________- The method of the state of motion of macroscopic objects cannot be used to describe the state of motion of microscopic particles.
5. In quantum mechanics, ______________ is used to describe the motion state of microscopic particles, and the square of the value represents _______________________.
6. The element with the largest first ionization energy is __________; the element with the largest electronegativity is _____________; the element with half-filled 3d orbital in the atom is ______; the element with half-filled 4p orbital in the atom is _______________.
7. There are 7 electrons on the electron shell of an element atom whose principal quantum number n is 4. The electron configuration of the outer shell of the element atom is ____________________, the number of unpaired electrons is ________________, and the distribution of electrons outside the nucleus is ____________________. The atomic number of the element is ___________, it is located in the _________ period, the ___________ group, and the highest oxidation number is _____________________.
8. The atomic orbitals contained in the fourth energy level group are ________________________.
9. In the periodic table of elements, periods are divided by ____________, and groups are divided by _______________. The difference in atomic structure between main group elements and subgroup elements is ______________________________.
10. Four elements, A, B, C, and D, are known, among which A is an element of the fourth period, and it can form a compound with an atomic ratio of 1:1 with D. B is an element in the d-block of the fourth period, and its highest positive oxidation number is +7. C and B are in the same period and have the same positive oxidation number. Ding is the most electronegative element among all elements.
A. Fill out the form below
Element valence shell configuration periodic group metal or nonmetal
First
Second
C
Man
B. Measure the electronegativity order of the four elements ___________________________.
11. If a new element No. 117 is found, its valence electron configuration is ________________, which belongs to the ___________ group of the ______ period, and its compound properties are similar to ___________.
Chapter 8 Chemical Bond and Molecular Structure
True or False
The bond energy of C=C is greater than the bond energy of C—C, and less than twice the bond energy of C—C. ( )
2. When two atoms are combined by a covalent single bond, the chemical bond is a σ bond; when two atoms are combined by a covalent multiple bond, the chemical bond is a π bond. ( )
3. The chemical bonds formed by the participation of hybrid orbitals are generally σ bonds. ( )
4. For polyatomic molecules, as long as the molecular structure is symmetrical, the molecule must be a non-polar molecule. ( )
5. The maximum number of covalent single bonds that an atom of an element can form is equal to the number of unpaired electrons contained in the atom of the element in the ground state. ( )
6. Dispersion force only exists between non-polar molecules. ( )
7. The spatial configuration of the BCl3 molecule is a plane triangle, while the spatial configuration of the NCl3 molecule is a triangular pyramid. ( )
8. The so-called SP3 hybridization refers to the mixing of 1 S electron and 3 P electrons. ( )
9. The lattice energy of ionic crystals is only related to ionic charge and ionic radius. ( )
10. If there are no unpaired electrons in the valence electron shell of the bonding atom, no covalent bond can be formed. ( )
2. Multiple Choice Questions
1. Which of the following molecules has both inductive force and orientation force ( )
A, CCl4 and benzene B, CHCl3 and H2O
C, CH4 and H2 D, CH2Cl2 and CO2
2. Covalent bonds are most likely to exist in ( )
A. Between metal atoms.
B. Between non-metal atoms.
C. Between non-metal atoms and metal atoms.
D. Between element atoms with very different electronegativity.
3. Which of the following ions has 18+2 electron configuration ( )
A、Na+ B、Ca2+ C、Fe2+ D、Pb2+
4. Among the following compounds, which one does not have a lone electron pair ( )
A、 H2O B、 NH3 C、NH4+ D、 H2S
5. All of the following substances are bonded by shared electron pairs ( )
A、 NH4Cl B、BF3 C、NaOH D、NaCl
6. Among the following compounds, the bond with the least polarity is ( )
A、 MgCl2 B、 AlCl3 C、SiCl4 D、 PCl5
7. Two corresponding atomic orbitals overlap in a "side by side" way ( )
A, σ bond B, π bond C, hydrogen bond D, ionic bond
8. When HCl molecules are formed, the atomic orbital overlap is ( )
A, S—S overlapping B, Py—Py overlapping
C, S—Px overlap D, Px—Py overlap
9. CCl4 boiling is ( )
A. Mainly break covalent bonds B. Mainly break metal bonds
C, mainly to overcome the intermolecular forces
D. Mainly overcome the electrostatic attraction between positive and negative ions
10. Among SiCl4 and C2H4 molecules ( )
A. There are π bonds in the molecule B. It is a polar molecule
C. There are hybrid orbitals in the molecule to form bonds
D. are non-polar molecules
11. The most polar of the following chemical bonds is ( )
A、H—F B、 S—H C、 H—O D、N—H
12. Which of the following molecules has both polar and non-polar bonds ( )
A、 NH4OH B、HCN C、 H2O2 D、CCl4
13. Predict the hybridization mode of SiHCl3 molecules according to the hybrid orbital theory ( )
A、SP B、 SP3 C、SP2 D、 dSP2
14. The central atom only bonds with SP hybrid orbitals ( )
A. BeCl2 and HgCl2 B. CO2 and CS2
C, H2S and H2O D, BF3 and CCl4
15. Which of the following statements is correct ( )
A. All molecules whose central atoms use SP3 hybrid orbitals to form bonds have a positive tetrabody geometry.
B. AB3-type covalent compounds, the central atoms of which all use SP2 hybrid orbitals to form bonds.
C. In AB2-type covalent compounds, the central atoms all use SP hybrid orbitals to form bonds.
D. SP3 hybridization can be divided into isotropic SP3 hybridization and unequal SP3 hybridization.
16. The molecular geometry of BeCl2 is linear, and the bond formed by Be and Cl is ( )
A、（SP2—P）σ key B、（SP—S）σ key
C, (SP—P) σ bond D, (SP—S) π bond
17. Judging the molecular configuration of SO3 using the theory of mutual repulsion of electron pairs in the valence shell is ( )
A. Regular tetrahedron B. V-shaped
C. Triangular cone D. Plane triangle
18. SiF4, NH4+ and BF4- have the same spatial configuration, the configuration is ( )
A. Triangular pyramid B. Regular tetrahedron C. Square D. Quadrilateral
19. Among the following substances, which one can boil just by overcoming the dispersion force ( )
A、 H2O(l) B、 Br2(l)
C、 CHCl3(l) D、 NH3(l)
20. The compound with zero dipole moment is ( )
A、CS2 B、NH3 C、H2S D、SO2
21. The strongest intermolecular force is ( )
A、 F2 B、 Cl2 C、 Br2 D、 I2
22. Which of the following crystals needs to break the covalent bond when melting ( )
A、CO2 B、SiO2 C、NaCl D、HCl
23. The lattice energy of MgO is ( )
A. Mg(s) + 1/2O2(g) = MgO(s) -ΔrHØm(1)
B. 2Mg(s) + O2(g) = 2MgO(s) -ΔrHØm(2)
C. Mg(g) + 1/2O2(g) = MgO(s) -ΔrHØm(3)
D. Mg2+(g) + O2-(g) = MgO(s) -ΔrHØm(4)
twenty four. If U is the lattice energy, I is the ionization energy, and D is the bond dissociation energy; which of the following is correct ( )
A、 Cl- Cl + e ΔHØ = I
B、 Na+ + e Na ΔHØ =U
C、 Cl2(g) 2 Cl(g) ΔHØ =D
D、 Na(s) Na(g) ΔHØ =D
25．In the electronic structure of the following ions, the number of unpaired electrons is zero ( )
A、 Ca2+ B、 Mn3+ C、 Pb2+ D、 Fe2+
26．The factors that affect the strength of the covalent bond are ( )
The characteristic of σ bond is ( )
The characteristic of π bond is ( )
Ionic bonds are characterized by ( )
A, non-directional, and saturation.
B. The degree of overlap of atomic orbitals.
C. Atomic orbitals overlap "head to head" along the bond axis, and the overlapping parts are cylindrically symmetrical along the bond axis.
D. The atomic orbitals overlap in a "side by side" manner, and the overlapping part passes through a bond axis plane, which has mirror antisymmetry.
27. Which of the following statements are correct? ( )
A. In polyatomic molecules, the stronger the polarity of the bond, the stronger the polarity of the molecule.
B. Molecules with polar covalent bonds must be polar molecules,
C. The chemical bonds in non-polar molecules must be non-polar covalent bonds,
D. The bonds in the molecule are non-polar bonds, and the molecules must be non-polar molecules.
28. Which of the following molecules has a dipole moment not equal to zero ( )
A、BeCl2 B、BCl3 C、CO2 D、NH3
29. Which of the following substances has the largest radius ( )
A. Na+ B. Ne CF- D. O2-
fill in the blank
When the S orbital and the P orbital are hybridized, there are several types of ______________, ___________, ___________. The spatial configurations of molecules formed by them and other atoms are ___________, ___________, ___________.
The Hg atom in the HgCl2 molecule adopts _________ hybridization, and the molecular space configuration is _________________ and the dipole moment of the molecule is ___________________.
The central atom O of the H3O+ ion adopts ____________ hybridization, in which there are ________ σ bonds and ___________ coordination bonds. The configuration of the valence electron pair of the central atom is _________________, and the geometric configuration of the ion is_ __________________.
The C atoms in CH4, C2H4, and C2H2 form bonds with other atoms by hybridization of _____________, ______________, and _____________ respectively. C2H2 molecular space configuration ____________, two C atoms form __________ σ bonds and _________ π bonds.
Whether a covalent bond is polar or not depends on ___________________; and whether a molecule has polarity depends on ____________________________.
There are __________________ forces between nonpolar molecules and _____________________ forces between polar molecules.
The order of molecular polarity of hydrogen halides HF, HCl, HBr, HI from strong to weak ________________________; the order of intermolecular orientation force from strong to weak is ______________________; The order from high to low is ____________________________.
8. The hybrid orbital type of the P atom in the PH3 molecule is __________________, the molecular space configuration is ________________, the hybridization method of the Se atom in the H2Se molecule is ________________, and the molecular space configuration is _____________________.
9. The bond energy of a diatomic molecule is its __________________.
10. It is known that element A is an element in the P block of the third period, and its lowest oxidation value is -1, and element B is an element in the d block of the fourth cycle, and its highest oxidation value is +4. Try to fill in the form below:
| element |
Valence electrons structure |
family |
metal or non-metal |
Electronegative phase high and low |
| First |
||||
| Second |
11. Fill out the form below:
| molecular formula |
The hybridization mode of the central atom |
Molecular configuration |
bond polarity |
Molecules are polar |
intermolecular force |
Molecular dipole moment (greater than less than) |
| CH4 |
||||||
| CH3Cl |
||||||
| CO2 |
12. Complete the form below:
| compound |
Number of σ bonds |
bond polarity |
Molecules are polar |
Molecular configuration |
σ bond orbital |
| BF3 |
SP2—P |
||||
| BeH2 |
straight line |
||||
| H2O |
|||||
| SiCl4 |
13. Two basic conditions for the formation of hydrogen bonds———————————————————————__________________________________________.
Chapter 9 Redox Reaction
1. Multiple choice questions
1. When KMnO4 reacts with H2O2, the following two reactions can be written __C_________
2KMnO4 +H2O2 +3H2SO4 = 2MnSO4 + K2SO4 +3O2 +4H2O
2KMnO4+5H2O2+3H2SO4 = 2MnSO4 + K2SO4 +5O2+4H2O
A. (1) formula is right B. (2) formula is right C. neither formula is right D. both formulas are right
2. There are three batteries
Tl | Tl+ || Tl3+, Tl | Pt
Tl | Tl3+ || Tl3+, Tl+ | Pt
Tl | Tl+ || Tl3+ |Tl
It is known that φΘTl+/Tl = -0.34V φΘTl3+/Tl = 0.74V
Assuming that the concentration of each substance in these three batteries is 0.1mol . L-1, then their _D_______
The battery reaction formula is different, ε is different
The battery reaction formula is different, ε is the same
The battery reaction formula is the same, ε is the same
The battery reaction formula is the same, but ε is different
3. The two half-cells have the same electrodes. After electrolysis, the substances in the solution are the same, and the electrode reaction can be carried out, but the concentration of the solution is different. Connect the two half-cells with a salt bridge and a wire. The electromotive force of this battery____B_______
A. εΘ= 0, ε = 0 B. εΘ= 0, ε ≠ 0
C. εΘ≠ 0, ε = 0 D. εΘ≠ 0, ε ≠ 0
4. A certain solution contains Cl-, Br-, I- three ions. It is required to oxidize only I- and leave Cl- and Br- in the solution, which oxidant C should be chosen—————
（ known φΘCl2/Cl- = 1.36V， φΘBr2/Br- = 1.07V,，φΘI2/I- = 0.54V）
A. φΘMnO4-/Mn2+ = 1.491V B. φΘCr2O7-/Cr3+= 1.33V
C. φΘFe3+/Fe2+= 0.770V D. φΘCu2+/Cu+= 0.3402V
5. It is known that Fe3+ + e = Fe2+'s φΘ = 0.770V, at 101325Pa and 298.15K, the measured electric pair Fe3+ /Fe2+'s φ = 0.750V, then the ion concentration in the electrode solution must be _____C_____
A. [Fe3+] > 1 mol.L-1 B. [Fe3+] < 1 mol.L-1
C. [Fe3+]/[ Fe2+] < 1 D. [Fe3+]/[ Fe2+] > 1
6. Insert two lead sheets into two Pb2+ solutions respectively to make electrodes I and II, and obtain electrode potentials respectively: φI = -0.13V, φII = -0.15V, indicating that [Pb2+] in the two solutions is _A________
A. I > II B. II > I C. I = II D. Unable to judge
7. Balance the following reactions: P4 (white phosphorus) + OH- → H2PO2- + PH4+, the coefficient of OH- is ___C______
A. 3 B. 4 C. 2 D. 1
8. It is known that in acidic medium, φΘMnO2/Mn2+ = 1.23V, when [Mn2+] =1.0mol . L-1, PH = 6, φΘMnO2/Mn2+ is equal to ____C_____V
A. 1.23 B. 0.71 C. 0.52 D. 1.94
9. Design the Zn + Cu2+ = Zn2+ + Cu reaction as a primary battery, if ammonia water is added to the copper half-cell solution, the battery electromotive force ε value will be___C_________
A. Increased B. Unchanged C. Decreased D. Unable to judge
10. Which of the following reactions can design a battery without using an inert electrode__D_______
Hg2Cl2(s) + H2(g) → H+ + Hg(l) + Cl-
Fe3+ + Ce3+ → Ce4+ + Fe2+
H2 + Cl2 → HCl2
Ca2+ + Ag + Cl- → Cu + AgCl(s)
11. It is known that φΘMnO2/Mn2+ = 1.23V, φΘCl2/2Cl- = 1.36V, from the standard electrode potential, MnO2 cannot oxidize Cl-, but adding concentrated hydrochloric acid to MnO2 can generate Cl2(g). This is because —D— ————
The difference between the two φΘ is not too big. B. The acidity increases, and the φMnO2/Mn2+ increases
C. [Cl-] increases, and φCl2/2Cl- decreases. D. There are all three factors above.
12. The electrode potential φ value of the following electric pair is not affected by the pH value of the medium is _C________
A. MnO2/Mn2+ B. H2O2/H2O
C. Br2/Br- D. S/H2S
13. The electric pair Fe3+/Fe2+ is used as the positive electrode, and Cu2+/Cu is used as the negative electrode to form a primary battery. The electromotive force is ε1. After ammonia water is added to the Cu2+/Cu electrode, the measured electromotive force is ε2. It can be inferred that A_______
A. ε2 >ε1 B. ε2 <ε1 C. ε2 =ε1
C, A, B, and C are all wrong.
14. In the following reactions, which of the substances under quotation marks is the reducing agent C___________
"Ferrous sulfide" and dilute hydrochloric acid
Copper and "hot concentrated sulfuric acid"
Add "H2O2 solution" to acidified KMnO4 aqueous solution
Introduce "sulfur dioxide" into hydrogen sulfuric acid
15. According to the following reaction
2FeCl3 + Cu → 2FeCl2 + CuCl2
2KMnO4 + 10FeSO4 + 8H2SO4
2MnSO4＋5Fe2(SO4)3 + K2SO4 + 8H2O
It is judged that the electric pair with the largest electrode potential is D——————
A．Fe3+/Fe2+ B. Cu2+/Cu
C. Mn2+/MnO4- D. MnO4-/Mn2+
16. Which of the following statements is correct B—————
The magnitude of the electrode potential can measure how easily a substance gains and loses electrons.
The standard electrode potential of an electrode is the potential difference of the electric double layer of the electrode.
In the primary battery, electrons flow from the negative electrode to the positive electrode through the wire, and then from the positive electrode to the negative electrode through the solution, thus forming an electrical circuit.
In a primary battery that actually supplies power, the pair with the larger electrode potential is always used as the positive electrode, and the pair with the lower electrode potential is used as the negative electrode.
17. Which of the following statements is correct ______
Because the φΘ of Ni2+ + 2e- = Ni is -0.25V, so the φΘ of 2Ni2+ + 4e- = 2Ni is -0.50V.
The oxidation ability of oxyacids usually increases with the decrease of the pH value of the solution.
Because φΘMnO2/Mn2+ < φΘCl2/2Cl-, Cl2 can never be produced by MnO2 and hydrochloric acid
It is known that the φΘ of Zn2+/Zn and Cu2+/Cu are -0.762V and 0.345V respectively, and the reason why the electromotive force of the copper-zinc primary battery is 1.105V is that the concentration of Cu2+ ions is larger than that of Zn2+ ions.
18. The φΘ of the electric pair I2/I- is 0.534V, at 250C, when the I- ion concentration is 0.1mol . L-1,
When φ is __________
A. 0.534V B. 0.650V C. 0.593V D. 0.471V
19. According to the following reaction 2S2O32- + I2 = S4O62- +2I- constitute the original battery, its E = 0.44V is measured. It is known that the φΘ of the electricity pair I2/I- is 0.534V, then the electricity pair S4O62- / S2O32 - φΘ is ____________
A. –0.090V B.0.978V C. 0.090V D.-0.978V
20. The standard electrode potential of the electric pair Fe3+ + e = Fe2+ is 0.771V, which means _____
A. Fe3+ is easier to be reduced than H+ B. Fe2+ is easier to be reduced than H+
C. Fe3+ is easier to be reduced than Fe2+ D. Fe is easier to be oxidized than H2
21. The φΘ of Zn2+/Zn = -0.762V, the value is determined in _________
A. PH = 0 B. PH = 1
C. PH = 2 D. PH = 3
22. Which of the following statements is wrong ________
In aqueous solution, the corresponding pair of the strongest reducing agent has the smallest electrode potential.
The direction of the redox reaction is always that the strong oxidized species oxidizes the stronger reduced species, corresponding to the formation of weaker reduced species and weaker oxidized species.
FeCl3 cannot react with elemental copper.
When preparing FeSO4 solution, adding iron nails can prevent Fe2+ from changing into Fe3+
23. In Pt|H2(101.325Pa) / H+(1mol . L-1) || Fe3+(1mol . L-1), Fe2+(1mol . L-1)| Pt battery, electron transfer is______
A. Fe2+→Fe3+ B. H2 →Fe3+
C. H2→H+ D. Fe2+→H+
24. Among the following electrical pairs, the one with the largest φΘ is _________
A. φΘ(AgCl/Ag) B. φΘ (AgI/Ag)
C. φΘ (Ag+/Ag) D. (AgBr/Ag)
25. Fe3+ can oxidize I- to I2, but FeF63- cannot oxidize I-, which shows that_______
φΘ (Fe3+/ Fe2+) > φΘ (Fe F63-/ Fe F64-)
φΘ (Fe3+/ Fe2+) = φΘ (Fe F63-/ Fe F64-)
φΘ (Fe3+/ Fe2+) < φΘ (Fe F63-/ Fe F64-)
It is impossible to determine which of the two electrodes has the greater potential.
26. In a certain solution, there are several reducing agents at the same time. If they all react with the same oxidizing agent in the standard state, the factors affecting the sequence of redox reactions are __________
reaction speed
The electrode potential difference between the oxidizing agent and the reducing agent.
It depends not only on the electrode potential difference between the oxidizing agent and the reducing agent, but also on the reaction rate.
concentration of oxidizing and reducing agents.
27. The so-called disproportionation reaction is ________
A reaction of an element itself.
A redox reaction of elements in a compound.
A redox reaction of an element.
A reaction in which the same oxidation state of the same element is redoxed to a different oxidation state.
28. The electrode potential of the electric pair Zn2+/Zn increases with the following changes:________
A. C(Zn2+) decreases B. C(Zn2+) increases
C. The area of the zinc sheet increases D. None of the three
29. Reaction 3A2+ + 2B = 3A + 2B3+ The electromotive force of the battery in the standard state is 1.80V. At a certain concentration, the electromotive force of the battery in the reaction is 1.60V. Then the lgKΘ of the reaction at this time ________
A. B.
C.
D.
30. It is known that PbSO4 + 2e = Pb + SO42- φΘ=-0.359V
Pb2+ + 2e = Pb φΘ=-0.126V
Then the solubility product of PbSO4 is ________
A. 3.40 x 10-7 B. 1.34 x 10-8
C. 1.20 x 10-6 D. 7.70 x 10-10
31. Use the standard electrode potential table to judge the direction of the redox reaction, the correct one is ________
The oxidized species reacts with the reduced species.
The oxidized species with a higher potential at the corresponding electrode reacts with the reduced species with a lower potential at the corresponding electrode.
A more oxidizing substance reacts with a less oxidizing substance.
More reducing substances react with less oxidizing substances.
32. φAΘ/V Au3+ Au+Au
According to the above potential diagram, the reaction that can be predicted to proceed spontaneously is _______
A. Au3+ + 2Au → 3Au+ B. Au + Au+ → 2Au3+
C. 2Au → 2Au3+ + Au+ D. 3Au+ → Au3+ + 2Au
33. According to the potential diagram of bromine element
φBΘ/V BrO3- BrO-Br2Br- can be obtained
φΘ(BrO-/Br) is ——————————
A．1.52V B. 0.76V C. 0.728V D. 0.364V
34. Given the following data
Cu+ + e = Cu φΘ = +0.522V
Cu2+ + e = Cu+ φΘ = +0.167V
Determine the EΘ of 2Cu+ → Cu+ Cu2+ as ———————————
A. +0.689V B. –0.689V C.-0.355V D. +0.355V
35. Design the reaction Ni + Cu2+ = Ni2+ + Cu as a primary battery, which of the following is the correct battery symbol? _______________
A、（－）With | Cu2+ || Ni2+ | We (+)
B、（－）Ni | Ni2+ || Cu2+ | With (+)
C、（－）With | Ni2+ || Cu2+ | We (+)
D、（－）Ni | Cu2+ || Ni2+ | With (+)
36. In order to improve the oxidation ability of Fe2(SO4)3, which of the following measures can be taken?
A. Increase the concentration of Fe3+ and decrease the concentration of Fe2+
B. Reduce the concentration of Fe3+ and increase the concentration of Fe2+
C. Increase the pH value of the solution
D. Lower the pH value of the solution
37. Among the following oxidizing agents, which substances have higher oxidizing properties as the concentration of H+ increases?
(1) Hg2+ (2) MnO42－ (3) Cr2O72－ (4) Cl2 (5) H2O2
A、（1）（4） B、（2）（3）（5） C、（2）（3）（4）（5）
D、（2）（3）
2. Multiple Choice Questions
1. In a redox reaction, the substance that obtains electrons is the ___________ agent and is __________. A substance that has lost electrons is a _____________ agent, itself ________________________.
2. It is known that the following reactions all proceed to the right:
2FeCl3 + SnCl2 → 2FeCl2 + SnCl4
2KMnO4+10FeSO4+8H2SO4→2MnSO4+5Fe2(SO4)3+K2SO4+8H2O
Among the above substances, the strongest oxidizing agent is _____________, and the strongest reducing agent is ___________.
3. According to the following reaction Fe + 2HCl = FeCl2 + H2 to form a primary battery, the positive electrode reaction formula ____________________________________ the negative electrode reaction formula _________________________________.
4. Connect the two poles of the primary battery with a wire, and a current will be generated. The direction of electron flow is from the __________ of the primary battery to _____________. The direction of the current is from the __________ of the primary battery to _____________.
5. In the reaction of H2O2 and PbS, ——————— is the oxidizing agent, ——————— is the reducing agent, and the product of the reaction is ———————.
6. At 250C, φΘMnO4-/Mn2+ = 1.15V, φΘSO4-/H2SO3 =0.20V, if the upper two electrodes are used to form a primary battery, write:
The standard state primary battery symbol is _____________________________________________
The balanced ionic reaction equation is ____________________________________________
The standard electromotive force EΘ is _______________________________
The standard equilibrium constant KΘ is ________________________________..
7. Known battery (-)Ag|AgCl|Cl-(1mol . L-1)||I-(1mol . L-1)|I2|Pt(+), the battery electrode reaction is ________________________________________, the positive electrode reaction ______________________________, negative reaction ________________________________.
8. Superoxide dismutase (SOD) acts as a "scavenger" for reducing harmful superoxide ions in organisms by catalyzing the disproportionation of superoxide ions into H2O2 and O2. The potential diagram of known elements:
O2
HO2
H2O2
1.08v
Then the standard electromotive force of SOD catalytic reaction 2HO2 → H2O2 + O2 is _________.
9. Disproportionation reaction __________________________________________________________________, according to
BrO3-
BrO-
Br2
Br－
0.76V
BrO-disproportionation produces ____________ and ______________.
10. When preparing SnCl2 solution, first add a certain amount of concentrated hydrochloric acid and then dilute with water for ____________________, and often add Sn particles in SnCl2 solution for ________________________.
11. According to the following standard electrode potential diagram of Mn element in acidic solution at 298.15K:
MnO4-MnO42-MnO2Mn3+Mn2+Mn
Point out that in the above element potential diagram, the disproportionation reaction can occur in aqueous solution is _________________________________________________
12. After KMnO4 and NaSO3 are reacted in a strong alkaline solution, the solution shows a ________ color. Write the ionic reaction (balanced) equation of the reaction ______________________________________.
2. Calculation questions
1. The following reaction at 298K
Cr2O72- + 6Fe2+ +14H+ = 2Cr3+ +6Fe3+ + 7H2O
Write the symbol of the primary battery formed by this reaction;
Calculate the equilibrium constant K for this reaction at ΔrGØ298K and 298K
When PH=2, the battery electromotive force ε when the concentration of other ions is 1mol . L-1
(It is known that φΘ (Cr2O72-/ Cr3+)=1.33V φΘ (Fe3+/ Fe2+)=0.77V)
2. The existing acidic KMnO4 and Pb(NO2)2 solutions are one cup each, and metal platinum (Pt) rods are selected to be inserted into the KMnO4 solution, and metal lead (Pb) rods are inserted into the Pb(NO2)2 solution. 1mol . L-1, φΘ (Pb2+/ Pb) = _0.126V, φΘ (MnO4-/ Mn2+) = +1.491V.
Try to judge the direction in which the galvanic reaction proceeds spontaneously.
Complete and balance the above galvanic cell reaction equation and the two-electrode reaction equation
Use the battery symbol to represent the original battery, and calculate its standard electromotive force and equilibrium constant.
3. When PH=5, [MnO4]=[Cl-1]=[Mn2+]=1mol . L-1, P(Cl2)=101325Pa, can the following reaction be used to prepare chlorine gas? Explain it by calculation.
2MnO4- + 10Cl- +16H+ = 2Mn2+ +5Cl2 + 8H2O
(φΘ (MnO4-/ Mn2+) = +1.491V. φΘ (Cl2/ Cl-) = +1.36V.)
4. At 298K, Fe3+/Fe2+ electrode [Fe3+]=1mol . L-1, [Fe2+]=0.1mol . L-1, and Cu2+/Cu electrode [Cu2+]=0.1mol . L-1, forming a primary battery.
It is known that φΘ (Fe3+/ Fe2+)=0.77V, φΘ (Cu2+/Cu)=0.337V
Write the battery symbol, electrode reaction and battery reaction of this primary battery
Calculate the value of the electromotive force ε.
Calculate the equilibrium constant K value of the battery reaction
5. For the same chemical reaction 2Tl + Tl3+ = 3Tl+, the following three primary batteries can be arranged in the standard state:
Tl |Tl + || Tl3+, Tl+ | Pt
Tl |Tl3+ || Tl3+, Tl+ | Pt
Tl | Tl+||Tl3+ | Tl
Calculate the electromotive force of each primary cell
( known φΘTl+/Tl = -0.34V, φΘTl3+/Tl = 0.72V, φΘTl3+/Tl+ = 1.25V ).