Consider a closed container with Cu(s), CuO(s), SO2(g), SO3(g), and O2(g) at 800 K.  When this system reaches equilibrium, there are 3 simultaneous chemical equilibria: (i)          2 Cu(s) + O2(g) ⇌ 2 CuO(s)                                               Kc(i) = 1.51 × 108(ii)         CuO(s) + SO2(g) ⇌ Cu(s) + SO3(g)                                Kc(ii) = 6.38 × 10–6(iii)       2 SO2(g) + O2(g) ⇌ 2 SO3(g)                                               Kc(iii) = ? Determine the value of the equilibrium constant Kc(iii) at 800 K.    1.56 × 105        6.87 × 10–12     Correct Answer    6.15 × 10–3     You Answered    1.51 × 108

In a solution with carbon tetrachloride as the solvent, the compound VCl4. undergoes dimerization: 2VCl4V2Cl8 When 6.6834 g VCl4. is dissolved in 100.0 g carbon tetrachloride, the freezing point is lowered by 5.97C. Calculate the value of the equilibrium constant for the dimerization of VCl4 at this temperature. (The density of the equilibrium mixture is 1.696 g/cm3, and Kf = 29.8C kg/mol for CCl4.)

The decomposition of PCl5(g) to form PCl3(g) and Cl2(g) has Kc = 33.3 at a high temperature. If the initial concentration of PCl5 is 0.1000 M, what are the equilibrium concentrations of the reactants and products?

Because calcium carbonate is a sink for CO32- in a lake, the student in Exercise 12.39 decides to go a step further and examine the equilibrium between carbonate ion and CaCOj. The reaction is Ca2+(aq) + COj2_(aq) ** CaCO,(s) The equilibrium constant for this reaction is 2.1 X 10*. If the initial calcium ion concentration is 0.02 AI and the carbonate concentration is 0.03 AI, what are the equilibrium concentrations of the ions? A student is simulating the carbonic acid—hydrogen carbonate equilibrium in a lake: H2COj(aq) H+(aq) + HCO}‘(aq) K = 4.4 X 10"7 She starts with 0.1000 AI carbonic acid. What are the concentrations of all species at equilibrium?

For the reactionH2(g)+I2(g)2HI(g), consider two possibilities: (a) you mix 0.5 mole of each reactant. allow the system to come to equilibrium, and then add another mole of H2 and allow the system to reach equilibrium again. or (b) you mix 1.5 moles of H2 and 0.5 mole of I2 and allow the system to reach equilibrium. Will the final equilibrium mixture be different for the two procedures? Explain.

What is the law of mass action? Is it true that the value of K depends on the amounts of reactants and products mixed together initially? Explain. Is it true that reactions with large equilibrium constant values are very fast? Explain. There is only one value of the equilibrium constant for a particular system at a particular temperature, but there is an infinite number of equilibrium positions. Explain.

Consider the following equilibria involving SO2(g) and their corresponding equilibrium constants. SO2(g) + 12 O2(g) SO3(g) K1 2SO3(g) 2SO2(g) + O2(g) K2 Which of the following expressions relates K1 to K2? (a) K2=K12 (b) K22=K1 (c) K2 = K1 (d) K2 = 1/K1 (e) K2=1/K12

Interconvert K, and Kc values. Calculate Kp for the following reactions at the indicated temperature. (a) PCl3(g) + Cl₂(g)=PCI5(g) Kc = 200 at 479 K Kp = (b) NH4l(s) NH3(g) + HI(g) K = 1.34×10-³ at 651 K Kp =

A 1.00-L flask was filled with 2.00 moles of gaseous SO2 and 2.00 moles of gaseous NO2 and heated. After equilibrium was reached, it was found that 1.30 moles of gaseous NO was present. Assume that the reaction SO2 (g) + NO2 (g) ⇌  SO3 (g) + NO (g) occurs under these conditions. Calculate the value of the equilibrium constant, K, for this reaction.

A student ran the following reaction in the laboratory at 652 K:2NH3(g) N2(g) + 3H2(g)When she introduced 8.25×10-2 moles of NH3(g) into a 1.00 liter container, she found the equilibrium concentration of NH3(g) to be 7.26×10-3 M.Calculate the equilibrium constant, Kc, she obtained for this reaction.Kc =