 # Determine the value of kc for the following reaction if the equilibrium concentrations are as follows

1) Define dynamic equilibrium.

• A) no reactants react
• B) no products are formed
• C) the rate of the forward reaction is faster than the rate of the reverse reaction
• D) the rate of the reverse reaction is faster than the rate of the forward reaction
• E) the rate of the forward reaction equals the rate of the reverse reaction

2) Which of the following statements is FALSE?

• A) When K >> 1, the forward reaction is favored and essentially goes to completion.
• B) When K << 1, the reverse reaction is favored and the forward reaction does not proceed to a great extent.
• C) When K ≈ 1, neither the forward or reverse reaction is strongly favored, and about the same amount of reactants and products exist at equilibrium.
• D) K >> 1 implies that the reaction is very fast at producing products.
• E) None of the above.

3) Give the direction of the reaction, if K >> 1.

• A) The forward reaction is favored.
• B) The reverse reaction is favored.
• C) Neither direction is favored.
• D) If the temperature is raised, then the forward reaction is favored.
• E) If the temperature is raised, then the reverse reaction is favored.

4) Give the direction of the reaction, if K << 1.

• A) The forward reaction is favored.
• B) The reverse reaction is favored.
• C) Neither direction is favored.
• D) If the temperature is raised, then the forward reaction is favored.
• E) If the temperature is raised, then the reverse reaction is favored.

5) Give the direction of the reaction, if K ≈ 1.

• A) The forward reaction is favored.
• B) The reverse reaction is favored.
• C) Neither direction is favored.
• D) If the temperature is raised, then the forward reaction is favored.
• E) If the temperature is raised, then the reverse reaction is favored.

6) Express the equilibrium constant for the following reaction.

CH4(g) + 2 O2(g) ⇔ CO2(g) + 2 H2O(g)

• A) K =
• B) K =
• C) K =
• D) K =
• E) K =

7) The equilibrium constant is given for one of the reactions below. Determine the value of the missing equilibrium constant.

H2(g) + Br2(g) –> HBr(g)         Kc = 3.8 × 104

HBr(g) –> H2(g) + Br2(g) Kc =   ?

• A) 1.9 × 104
• B) 5.3 × 10-5
• C) 2.6 × 10-5
• D) 6.4 × 10-4
• E) 1.6 × 103

8) Express the equilibrium constant for the following reaction.

Pb(NO3)2(aq) + 2 NaI(aq)   ⇌ PbI2(s) + 2 NaNO3(aq)

9) Express the equilibrium constant for the following reaction.

4 Al(s) + 3 O2(g)   ⇌ 2 Al2O3(s)

10) Determine the value of Kc for the following reaction if the equilibrium concentrations are as follows: [P4O10]eq = 2.000 moles, [P4]eq = 3.000 moles, [O2]eq = 4.000 M

P4O10(s) ⇌ P4(s) + 5 O2(g)

• A) 20.00
• B) 4.000
• C) 1.320
• D) 1536
• E) 1024

11) Determine the value of Kc for the following reaction if the equilibrium concentrations are as follows: [N2]eq = 3.6 M, [O2]eq = 4.1 M, [N2O]eq = 3.3 × 10-18 M.

2 N2(g) + O2(g) ⇌ 2 N2O(g)

• A) 2.2 × 10-19
• B) 4.5 × 1018
• C) 2.0 × 10-37
• D) 5.0 × 1036
• E) 4.9 × 10-17

12) Determine the value of Kc for the following reaction if the equilibrium concentrations are as follows: [N2]eq = 1.5 M, [H2]eq = 1.1 M, [NH3]eq = 0.47 M.

N2(g) + 3 H2(g) ⇌ 2 NH3(g)

• A) 3.5
• B) 0.28
• C) 9.1
• D) 0.11
• E) 0.78

13) Determine the value of Kc for the following reaction if the equilibrium concentrations are as follows: [HCl]eq = 0.13 M, [HI]eq = 5.6 × 10-16 M, [Cl2]eq = 0.0019 M.

2 HCl(g) + I2(s) ⇌ 2 HI(g) + Cl2(g)

• A) 8.2 × 10-18
• B) 2.8 × 1031
• C) 1.2 × 1017
• D) 1.4 × 10-19
• E) 3.5 × 10-32

14) Determine the value of Kc for the following reaction if the equilibrium concentrations are as follows: [HCl]eq = 0.13 M, [HI]eq = 5.6 × 10-16 M, [Cl2]eq = 0.0019 M.

2 HI(g) + Cl2(g) ⇌ 2 HCl(g) + I2(s)

• A) 8.2 × 10-18
• B) 2.8 × 1031
• C) 1.2 × 1017
• D) 1.4 × 10-19
• E) 3.5 × 10-32

15) Calculate the value of [N2]eq if [H2]eq = 2.0 M, [NH3]eq = 0.5 M, and Kc = 2.

N2(g) + 3 H2(g) ⇌ 2 NH3(g)

• A) 0.016 M
• B) 0.031 M
• C) 0.062 M
• D) 0.40 M
• E) 62.5 M

16) Consider the following reaction, equilibrium concentrations, and equilibrium constant at a particular temperature. Determine the equilibrium concentration of SO3(g).

2 SO2(g) + O2(g) ⇌ 2 SO3(g)       Kc = 1.7 × 108

[SO2]eq = 0.0034 M    [O2]eq = 0.0018 M

• A) 1.9 M
• B) 1.0 × 103 M
• C) 0.53 M
• D) 9.6 × 10-4 M
• E) 0.73 M

17) Consider the following reaction, equilibrium concentrations, and equilibrium constant at a particular temperature. Determine the equilibrium concentration of SO2(g).

2 SO2(g) + O2(g) ⇌ 2 SO3(g)       Kc = 1.7 × 108

[SO3]eq = 0.0034 M    [O2]eq = 0.0018 M

• A) 2.8 × 1013 M
• B) 1.88 M
• C) 6.1 × 10-6 M
• D) 1.0 × 103 M
• E) 1.4 M

18) Which of the following is true about a system at equilibrium?

• A) The concentration(s) of the reactant(s) is equal to the concentration(s) of the product(s).
• B) No new product molecules are formed.
• C) The concentration(s) of reactant(s) is constant over time.
• D) The rate of the reverse reaction is equal to the rate of the forward reaction and both rates are equal to zero.
• E) None of the above (A-D) is true.

19) For a particular system at a particular temperature there ______ equilibrium constant(s) and there _______ equilibrium position(s).

• A) are infinite; is one
• B) is one; are infinite
• C) is one; is one
• D) are infinite; are infinite
• E) none of these

20) Consider the following reaction at equilibrium. What effect will increasing the pressure of the reaction mixture have on the system?

CuS(s) + O2(g) ⇌ Cu(s) + SO2(g)

• A) The equilibrium constant will decrease.
• B) No effect will be observed.
• C) The reaction will shift to the right in the direction of products.
• D) The equilibrium constant will increase.
• E) The reaction will shift to the left in the direction of reactants. Can’t find the questions that you need?