Ice Problem Set

Chemical Equilibrium

Problem Set # 2

MMXv.1

Instructions: Write your answer in one whole sheet of paper using black/blue pen. You may use additional sheets when needed. Show your solution and box final answers. Erasures should be made using correction tape/fluid. Write legibly. A. For the following reaction, KC = 2.00 at 1000.0oC: 2COF2 (g)  CO2 (g) + CF4 (g) If a 5.00 L mixture contains 0.145 mol COF2, 0.262 mol CO2, and 0.262 mol CF4 at 1000oC. Calculate the equilibrium concentration of all species. B. The gas-phase dissociation of phosphorus pentachloride to the trichloride has KP = 3.60 at 540°C: PCl5  PCl3 + Cl2. What will be the partial pressures of all three components if 0.200 mole of PCl5 and 3.00 moles of PCl3 are combined and brought to equilibrium at this temperature and at a total pressure of 1.00 atm? C. H2(g) + I2(g)  2HI(g). When 46.0 g of I2 and 1.00 g of H2 are heated to equilibrium at 4700C, the equilibrium mixture contains 1.90 g I2. (a) How many mole of each gas are present in the equilibrium mixture? (b) Compute the equilibrium constant? H = 1.0 g/mol I = 126.9 g/mol D. The equilibrium constant for the reaction CO(g) + H2O(g)  CO2(g) + H2(g) at 9860C is 0.63. A mixture of 1.00 mole of water vapor and 3.00 mole of CO is allowed to come to equilibrium at a total pressure of 2.00 atm. (a) How many mole of H2 are present at equilibrium? (b) What are the partial pressures of the gases in the equilibrium mixture? E. CO2 was passed over graphite at 1000 K. The emerging gas stream consisted of 28 mole % CO2 and 72 mole % CO. The total pressure at equilibrium was 2.00 atm. Assume that equilibrium was attained, calculate (a) the equilibrium concentrations of CO2 and CO. (b) Find KC for the reaction: C(s) + CO2 (g)  2CO (g).