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Problem 1a
(a) Based on the following energy profile, predict whether kf > kr or kf < kr. [Section 15.1]
Problem 2
The following diagrams represent a hypothetical reaction A Β‘ B, with A represented by red spheres and B represented by blue spheres. The sequence from left to right represents the system as time passes. Does the system reach equilibrium? If so, in which diagram(s) is the system in equilibrium? [Sections 15.1 and 15.2]
- Consider the equilibrium Na2O(s) + SO2(g) β Na2SO3(s). (a) Write the equilibrium-constant expression for this reaction in terms of partial pressures. (b) All the compounds in this reaction are soluble in water. Rewrite the equilibrium-constant expression in terms of molarities for the aqueous reaction.
Problem 3
Problem 4d
The following diagram represents a reaction shown going to completion. Each molecule in the diagram represents 0.1 mol, and the volume of the box is 1.0 L. (d) Assuming that all of the molecules are in the gas phase, calculate n, the change in the number of gas molecules that accompanies the reaction. [Section 15.2]
Problem 6
Ethene (C2H4) reacts with halogens (X2) by the following reaction:
C2H4(π) + X2(π) β C2H4X2(π)
The following figures represent the concentrations at equilibrium at the same temperature when X2 is Cl2 (green), Br2 (brown), and I2 (purple). List the equilibria from smallest to largest equilibrium constant. [Section 15.3]
Problem 8a
When lead(IV) oxide is heated above 300Β°C, it decomposes according to the reaction, 2 PbO2(π ) β 2PbO(π ) + O2(π). Consider the two sealed vessels of PbO2 shown here. If both vessels are heated to 400Β°C and allowed to come to equilibrium, which of the following statements is or are true? a. There will be less PbO2 remaining in vessel A than in vessel B.
Problem 8b
When lead(IV) oxide is heated above 300Β°C, it decomposes according to the reaction, 2 PbO2(π )β2PbO(π )+O2(π). Consider the two sealed vessels of PbO2 shown here. If both vessels are heated to 400Β°C and allowed to come to equilibrium, which of the following statements is or are true?
b. The solid left at the bottom of each vessel will be a mixture of PbO2(π ) and PbO(π ).
Problem 8c
When lead(IV) oxide is heated above 300Β°C, it decomposes according to the reaction, 2 PbO2(π )β2PbO(π )+O2(π). Consider the two sealed vessels of PbO2 shown here. If both vessels are heated to 400Β°C and allowed to come to equilibrium, which of the following statements is or are true? c. The partial pressure of O2(π) will be the same in vessels A and B. [Section 15.4]
Problem 9a
The reaction A2 + B2 β 2 AB has an equilibrium constant Kc = 1.5. The following diagrams represent reaction mixtures containing A2 molecules (red), B2 molecules (blue), and AB molecules. (a) Which reaction mixture is at equilibrium?
Problem 10a
The diagram shown here represents the equilibrium state for the reaction A2(π) + 2B(π) β 2AB(π). (a) Assuming the volume is 2 L, calculate the equilibrium constant πΎπ for the reaction.
Problem 13
Suppose that the gas-phase reactions A β B and B β A are both elementary reactions with rate constants of 4.7Γ10β3β sβ1 and 5.8Γ10β1 sβ1, respectively. (a) What is the value of the equilibrium constant for the equilibrium A(g) β B(g)? (b) Which is greater at equilibrium, the partial pressure of A or the partial pressure of B?