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Problem 52
For the equilibrium Br2(π) + Cl2(π) β 2 BrCl(π) at 400 K, πΎπ = 7.0. If 0.25 mol of Br2 and 0.55 mol of Cl2 are introduced into a 3.0-L container at 400 K, what will be the equilibrium concentrations of Br2, Cl2, and BrCl?
Problem 53
At 373 K, πΎπ = 0.416 for the equilibrium 2 NOBr(π) β 2 NO(π) + Br2(π) If the pressures of NOBr(π) and NO(π) are equal, what is the equilibrium pressure of Br2(π)?
Problem 54
At 218Β°C, πΎπ = 1.2Γ10β4 for the equilibrium NH4SH(π ) β NH3(π) + H2S(π) Calculate the equilibrium concentrations of NH3 and H2S if a sample of solid NH4SH is placed in a closed vessel at 218Β°C and decomposes until equilibrium is reached.
- Consider the reaction \( \text{CaSO}_4(\text{s}) \rightleftharpoons \text{Ca}^{2+}(\text{aq}) + \text{SO}_4^{2-}(\text{aq}) \) At 25 Β°C, the equilibrium constant is \( K_c = 2.4 \times 10^{-5} \) for this reaction. (a) If excess \( \text{CaSO}_4(\text{s}) \) is mixed with water at 25 Β°C to produce a saturated solution of \( \text{CaSO}_4 \), what are the equilibrium concentrations of \( \text{Ca}^{2+} \) and \( \text{SO}_4^{2-} \)? (b) If the resulting solution has a volume of 1.4 L, what is the minimum mass of \( \text{CaSO}_4(\text{s}) \) needed to achieve equilibrium?
Problem 55
Problem 56a
At 80Β°C, πΎπ = 1.87Γ10β3 for the reaction PH3BCl3(π ) β PH3(π) + BCl3(π) (a) Calculate the equilibrium concentrations of PH3 and BCl3 if a solid sample of PH3BCl3 is placed in a closed vessel at 80Β°C and decomposes until equilibrium is reached.
Problem 56b
At 80Β°C, πΎπ = 1.87Γ10β3 for the reaction PH3BCl3(π ) β PH3(π) + BCl3(π) (a) Calculate the equilibrium concentrations of PH3 and BCl3 if a solid sample of PH3BCl3 is placed in a closed vessel at 80Β°C and decomposes until equilibrium is reached. (b) If the flask has a volume of 0.250 L, what is the minimum mass of PH3BCl3(π ) that must be added to the flask to achieve equilibrium?
- For the reaction I2(g) + Br2(g) β 2 IBr(g), Kc = 280 at 150 _x001F_C. Suppose that 0.500 mol IBr in a 2.00-L flask is allowed to reach equilibrium at 150 _x001F_C. What are the equilibrium concentrations of IBr, I2, and Br2?
Problem 57
Problem 58
At 25Β°C, the reaction CaCrO4(π ) β Ca2+(ππ) + CrO42β(ππ) has an equilibrium constant πΎπ = 7.1Γ10β4. What are the equilibrium concentrations of Ca2+ and CrO42β in a saturated solution of CaCrO4?
- Methane, CH4, reacts with I2 according to the reaction CH4(g) + I2(g) β CH3I(g) + HI(g). At 630 K, Kp for this reaction is 2.26 Γ 10^-4. A reaction was set up at 630 K with initial partial pressures of methane at 105.1 torr and I2 at 7.96 torr. Calculate the pressures, in torr, of all reactants and products at equilibrium.
Problem 59
Problem 61e
Consider the following equilibrium, for which Ξπ»<0
2 SO2(π) + O2(π) β 2 SO3(π)
(e) the total pressure of the system is increased by adding a noble gas
Problem 61f
Consider the following equilibrium, for which Ξπ»<0
2 SO2(π) + O2(π) β 2 SO3(π)
(f) How will each of the following changes affect an equilibrium mixture of the three gases: SO3(π) is removed from the system?
Problem 62a,b,c
Consider the reaction 4 NH3(π) + 5 O2(π) β 4 NO(π) + 6 H2O(π), Ξπ» = β904.4 kJ Does each of the following increase, decrease, or leave unchanged the yield of NO at equilibrium? (a) increase [NH3] (b) increase [H2O] (c) decrease [O2]
Problem 62d
Consider the reaction 4 NH3(π) + 5 O2(π) β 4 NO(π) + 6 H2O(π), Ξπ» = β904.4 kJ Does each of the following increase, decrease, or leave unchanged the yield of NO at equilibrium? (d) decrease the volume of the container in which the reaction occurs
Problem 62e
Consider the reaction 4 NH3(π) + 5 O2(π) β 4 NO(π) + 6 H2O(π), Ξπ» = β904.4 kJ Does each of the following increase, decrease, or leave unchanged the yield of NO at equilibrium? (e) add a catalyst
Problem 62f
Consider the reaction 4 NH3(π) + 5 O2(π) β 4 NO(π) + 6 H2O(π), Ξπ» = β904.4 kJ Does each of the following increase, decrease, or leave unchanged the yield of NO at equilibrium? (f) increase temperature.
- How do the following changes affect the value of the equilibrium constant for a gas-phase exothermic reaction: (a) removal of a reactant, (b) removal of a product?
Problem 63
- For a certain gas-phase reaction, the fraction of products in an equilibrium mixture is increased by either increasing the temperature or by increasing the volume of the reaction vessel. Does the balanced chemical equation have more molecules on the reactant side or product side?
Problem 64
Problem 65a
Consider the following equilibrium between oxides of nitrogen 3 NO(g) β NO2(g) + N2O(g) (a) Use data in Appendix C to calculate ΞHΒ° for this reaction.
Problem 65c
Consider the following equilibrium between oxides of nitrogen
3 NO(g) β NO2(g) + N2O(g)
(c) At constant temperature, would a change in the volume of the container affect the fraction of products in the equilibrium mixture?
Problem 66a
Methanol (CH3OH) can be made by the reaction of CO with H2: CO(π) + 2 H2(π) β CH3OH(π) (a) Use thermochemical data in Appendix C to calculate ΞHΒ° for this reaction.
Problem 66b
Methanol (CH3OH) can be made by the reaction of CO with H2: CO(π) + 2 H2(π) β CH3OH(π) (b) To maximize the equilibrium yield of methanol, would you use a high or low temperature?
Problem 66c
Methanol (CH3OH) can be made by the reaction of CO with H2: CO(π) + 2 H2(π) β CH3OH(π) (c) To maximize the equilibrium yield of methanol, would you use a high or low pressure?
Problem 67
Ozone, O3, decomposes to molecular oxygen in the stratosphere according to the reaction 2 O31g2Β‘3 O21g2. Would an increase in pressure favor the formation of ozone or of oxygen?
- The waterβgas shift reaction CO1g2 + H2O1g2Ξ CO21g2 + H21g2 is used industrially to produce hydrogen. The reaction enthalpy is H = -41 kJ. (b) Could you increase the equilibrium yield of hydrogen by controlling the pressure of this reaction? If so would high or low pressure favor formation of H2(g)?
Problem 68
Problem 69a
(a) Is the dissociation of fluorine molecules into atomic fluorine, F2(π) β 2 ββF(π), an exothermic or endothermic process?
Problem 69b
(b) If the temperature is raised by 100 K, does the equilibrium constant for this reaction increase or decrease?
- Both the forward reaction and the reverse reaction in the following equilibrium are believed to be elementary steps: CO(g) + Cl2(g) Ξ COCl(g) + Cl(g). At 25 _x001F_C, the rate constants for the forward and reverse reactions are 1.4 * 10^-28 M^-1 s^-1 and 9.3 * 10^10 M^-1 s^-1, respectively. (a) What is the value for the equilibrium constant at 25 _x001F_C? (b) Are reactants or products more plentiful at equilibrium?
Problem 71
- If Kc = 1 for the equilibrium 2A β B, what is the relationship between [A] and [B] at equilibrium?
Problem 72
- A mixture of CH4 and H2O is passed over a nickel catalyst at 1000 K. The emerging gas is collected in a 5.00-L flask and is found to contain 8.62 g of CO, 2.60 g of H2, 43.0 g of CH4, and 48.4 g of H2O. Assuming that equilibrium has been reached, calculate Kc and Kp for the reaction CH4(g) + H2O(g) β CO(g) + 3H2(g).
Problem 73
- When 2.00 mol of SO2Cl2 is placed in a 2.00-L flask at 303 K, 56% of the SO2Cl2 decomposes to SO2 and Cl2: SO2Cl2(g) β SO2(g) + Cl2(g). Use the equilibrium constant you calculated above to determine the percentage of SO2Cl2 that decomposes when 2.00 mol of SO2Cl2 is placed in a 15.00-L vessel at 303 K.
Problem 74