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Problem 25a,b
At 1000 K, πΎπ = 1.85 for the reaction SO2(π) + 1/2 O2(π) β SO3(π) (a) What is the value of Kp for the reaction SO3(π) β SO2(π) + 1/2 O2(π)? (b) What is the value of Kp for the reaction 2 SO2(π) + O2(π) β 2 SO3(π)?
Problem 25c
At 1000 K, πΎπ = 1.85 for the reaction SO2(π) + 12 O2(π) β SO3(π) (c) What is the value of πΎπ for the reaction in part (b)?
Problem 26a
Consider the following equilibrium, for which πΎπ = 0.0752 at 480Β°C: 2 Cl2(π) + 2 H2O(π) β 4 HCl(π) + O2(π) (a) What is the value of πΎπ for the reaction 4 HCl(π) + O2(π) β 2 Cl2(π) + 2 H2O(π)?
Problem 26b
Consider the following equilibrium, for which Kp = 0.0752 at 480Β°C: 2 Cl2(g) + 2 H2O(g) β 4 HCl(g) + O2(g) (b) What is the value of Kp for the reaction Cl2(g) + H2O(g) β 2 HCl(g) + 1/2 O2(g)?
Problem 27
The following equilibria were attained at 823 K:
CoO(s) + H2(g) β Co(s) + H2O(g) Kc = 67
CoO(s) + CO(g) β Co(s) + CO2(g) Kc = 490
Based on these equilibria, calculate the equilibrium constant for H2(g) + CO2(g) β CO(g) + H2O(g) at 823 K.
Problem 28
Consider the equilibrium N2(π) + O2(π) + Br2(π) β 2 NOBr(π) Calculate the equilibrium constant πΎπ for this reaction, given the following information at 298 K:
2 NO(π) + Br2(π) β 2 NOBr(π) πΎπ = 2.02
NO(π) β N2(π) + O2(π) πΎπ = 2.1Γ1030
- Mercury(I) oxide decomposes into elemental mercury and elemental oxygen: 2 Hg2O(s) β 4 Hg(l) + O2(g). (a) Write the equilibrium-constant expression for this reaction in terms of partial pressures. (b) Suppose you run this reaction in a solvent that dissolves elemental mercury and elemental oxygen. Rewrite the equilibrium-constant expression in terms of molarities for the reaction, using (solv) to indicate solvation.
Problem 29
- Methanol (CH3OH) is produced commercially by the catalyzed reaction of carbon monoxide and hydrogen: CO(g) + 2 H2(g) β CH3OH(g). An equilibrium mixture in a 2.00-L vessel is found to contain 0.0406 mol CH3OH, 0.170 mol CO, and 0.302 mol H2 at 500 K. Calculate Kc at this temperature.
Problem 31
- Gaseous hydrogen iodide is placed in a closed container at 425 Β°C, where it partially decomposes to hydrogen and iodine: 2 HI(g) β H2(g) + I2(g). At equilibrium, it is found that [HI] = 3.53 Γ 10β»Β³ M, [H2] = 4.79 Γ 10β»β΄ M, and [I2] = 4.79 Γ 10β»β΄ M. What is the value of Kc at this temperature?
Problem 32
Problem 33a
The equilibrium 2 NO(π) + Cl2(π) β 2 NOCl(π) is established at 500.0 K. An equilibrium mixture of the three gases has partial pressures of 0.095 atm, 0.171 atm, and 0.28 atm for NO, Cl2, and NOCl, respectively. (a) Calculate πΎπ for this reaction at 500.0 K.
Problem 33b
The equilibrium 2 NO(π) + Cl2(π) β 2 NOCl(π) is established at 500.0 K. An equilibrium mixture of the three gases has partial pressures of 0.095 atm, 0.171 atm, and 0.28 atm for NO, Cl2, and NOCl, respectively. (b) If the vessel has a volume of 5.00 L, calculate Kc at this temperature.
- Phosphorus trichloride gas and chlorine gas react to form phosphorus pentachloride gas: PCl3(g) + Cl2(g) β PCl5(g). A 7.5-L gas vessel is charged with a mixture of PCl3(g) and Cl2(g), which is allowed to equilibrate at 450 K. At equilibrium, the partial pressures of the three gases are P(PCl3) = 0.124 atm, P(Cl2) = 0.157 atm, and P(PCl5) = 1.30 atm. (b) Does the equilibrium favor reactants or products? (c) Calculate Kc for this reaction at 450 K.
Problem 34
Problem 34a
Phosphorus trichloride gas and chlorine gas react to form phosphorus pentachloride gas: PCl3(π) + Cl2(π) β PCl5(π). A 7.5-L gas vessel is charged with a mixture of PCl3(π) and Cl2(π), which is allowed to equilibrate at 450 K. At equilibrium the partial pressures of the three gases are πPCl3 = 0.124 atm, πCl2 = 0.157 atm, and πPCl5 = 1.30 atm. (a) What is the value of πΎπ at this temperature?
- A mixture of 0.10 mol of NO, 0.050 mol of H2, and 0.10 mol of H2O is placed in a 1.0-L vessel at 300 K. The following equilibrium is established: 2 NO(g) + 2 H2(g) β N2(g) + 2 H2O(g). At equilibrium [NO] = 0.062 M. (a) Calculate the equilibrium concentrations of H2, N2, and H2O.
Problem 35
- A mixture of 1.374 g of H2 and 70.31 g of Br2 is heated in a 2.00-L vessel at 700 K. These substances react according to H2(g) + Br2(g) β 2 HBr(g). At equilibrium, the vessel is found to contain 0.566 g of H2. (a) Calculate the equilibrium concentrations of H2, Br2, and HBr.
Problem 36
Problem 37d
A mixture of 0.2000 mol of CO2, 0.1000 mol of H2, and 0.1600 mol of H2O is placed in a 2.000-L vessel. The following equilibrium is established at 500 K: CO2(g) + H2(g) β CO(g) + H2O(g) (d) Calculate Kc for the reaction.
- A flask is charged with 1.500 atm of N2O4 and 1.00 atm NO2 at 25 _x001F_C, and the following equilibrium is achieved: N2O4(g) β 2 NO2(g). After equilibrium is reached, the partial pressure of NO2 is 0.512 atm. (b) Calculate the value of Kp for the reaction. (c) Calculate Kc for the reaction.
Problem 38
- Two different proteins X and Y are dissolved in aqueous solution at 37 _x001F_C. The proteins bind in a 1:1 ratio to form XY. A solution that is initially 1.00 mM in each protein is allowed to reach equilibrium. At equilibrium, 0.20 mM of free X and 0.20 mM of free Y remain. What is Kc for the reaction?
Problem 39
Problem 41a
(a) If Qc < Kc, in which direction will a reaction proceed in order to reach equilibrium?
Problem 41b
(b) What condition must be satisfied so that Qc = Kc?
Problem 42a
(a) If Qc > Kc, how must the reaction proceed to reach equilibrium?
Problem 42b
(b) At the start of a certain reaction, only reactants are present; no products have been formed. What is the value of Qc at this point in the reaction?
Problem 43
At 100Β°C, the equilibrium constant for the reaction COCl2(π) β CO(π) + Cl2(π) has the value πΎπ = 2.19Γ10β10. Are the following mixtures of COCl2, CO, and Cl2 at 100Β°C at equilibrium? If not, indicate the direction that the reaction must proceed to achieve equilibrium.
(a) [COCl2] = 2.00Γ10β3 M, [CO] = 3.3Γ10β6 M, [Cl2] = 6.62Γ10β6 M
(b) [COCl2] = 4.50Γ10β2 M, [CO] = 1.1Γ10β7 M, [Cl2] = 2.25Γ10β6 M
(c) [COCl2] = 0.0100 M, [CO] = [Cl2] = 1.48Γ10β6 M
- As shown in Table 15.2, Kp for the equilibrium N2(g) + 3 H2(g) β 2 NH3(g) is 4.51 * 10^-5 at 450 _x001F_C. For each of the mixtures listed here, indicate whether the mixture is at equilibrium at 450 _x001F_C. If it is not at equilibrium, indicate the direction (toward product or toward reactants) in which the mixture must shift to achieve equilibrium. (a) 98 atm NH3, 45 atm N2, 55 atm H2. (b) 57 atm NH3, 143 atm N2, no H2. (c) 13 atm NH3, 27 atm N2, 82 atm H2.
Problem 44
- At 100 _x001F_C, Kc = 0.078 for the reaction SO2Cl2(g) β SO2(g) + Cl2(g). In an equilibrium mixture of the three gases, the concentrations of SO2Cl2 and SO2 are 0.108 M and 0.052 M, respectively. What is the partial pressure of Cl2 in the equilibrium mixture?
Problem 45
Problem 46
At 900 K, the following reaction has πΎπ = 0.345: 2 SO2(π) + O2(π) β 2 SO3(π) In an equilibrium mixture the partial pressures of SO2 and O2 are 0.135 atm and 0.455 atm, respectively. What is the equilibrium partial pressure of SO3 in the mixture?
- At 1285 _x001F_C, the equilibrium constant for the reaction Br2(g) β 2 Br(g) is Kc = 1.04 * 10^-3. A 0.200-L vessel containing an equilibrium mixture of the gases has 0.245 g of Br2(g) in it. What is the mass of Br(g) in the vessel?
Problem 47
- For the reaction H2(g) + I2(g) β 2 HI(g), Kc = 55.3 at 700 K. In a 2.00-L flask containing an equilibrium mixture of the three gases, there are 0.056 g H2 and 4.36 g I2. What is the mass of HI in the flask?
Problem 48
- At 800 K, the equilibrium constant for the reaction I2(g) β 2 I(g) is Kc = 3.1 * 10^-5. If an equilibrium mixture in a 10.0-L vessel contains 2.67 * 10^-2 g of I(g), how many grams of I2 are in the mixture?
Problem 49
Problem 51
At 2000Β°C, the equilibrium constant for the reaction 2 NO(π) β N2(π) + O2(π) is πΎπ = 2.4Γ103. If the initial concentration of NO is 0.175 M, what are the equilibrium concentrations of NO, N2, and O2?