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### Solution libraryQuestion: 733041

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Chemical Kinetics/Chemical Equilibrium/Acids and Bases 1. The following data were collected for the rate of disappearance of NO in the reaction 2NO(g)+O2(g)-----> 2NO2(g) Experiment [NO](M) [O2](M) Initial Rate(M/s) 1 0.0126 0.0125 1.41 x 10^-2 2 0.0252 0.0250 1.13 x 10^-1 3 0.0252 0.0125 5.64 x 10^-2 a) What is the rate law for the reaction? b) What are the units of the rate constant? c) What is the average value of the rate constant calculated from the three data sets? d) What is the rate of disappearance of NO when [NO]= 0.100 M and [O2]= 0.0200 M? e) What is the rate of disappearance of O2 at the concentrations given in part (d)? 2. From the following data for the first-order gas-phase isomerization of CH3NC at 215 degrees Celsius, calculate the first-order rate constant and half-life for the reaction: Time(s) Pressure CH3NC(torr) 0 502 2000 335 5000 180 8000 95.5 12000 41.7 15000 22.4 3. a) The activation energy for the isomerization of methyl isonitrile is 160kJ/mol. Calculate the fraction of methyl isonitrile molecules that have an energy of 160.0kJ or greater at 500 K. b) Calculate this fraction for a temperature of 510 K. What is the ratio of the fraction at 510 K to that at 500 K? 4. The decomposition of hydrogen peroxide is catalyzed by iodide ion. The catalyzed reaction is thought to proceed by a two-step mechanism. H2O2(aq)+ I-(aq)--->H2O(l)+ IO-(aq) [slow] IO-(aq) + H2O2(aq)--->H2O(l) + O2(g) + I-(aq) [fast] a)Write the rate law for each of the elementary reactions of the mechanism. b) Write the chemical equation for the overall process. c) Identify the intermediate, if any, in the mechanism. d) Assuming that the first step of the mechanism is rate determining, predict the rate law for the overall process. 5. Cyclopentadiene(C5H6) reacts with itself to form dicyclopentadiene(C10H12). A 0.0400M solution of C5H6 was monitored as a function of time as the reaction 2 C5H6-----> C10H12 proceeded. The following data was collected: Time(s) [C5H6](M) 0.0 0.0400 50.0 0.0300 100.0 0.0240 150.0 0.0200 200.0 0.0174 Plot [C5H6] versus time, In [C5H6] versus time, and 1/[C5H6] versus time. What is the order of the reaction? What is the value of the rate constant? 6. a)Two reactions have identical values for Ea(activation energy). Does this ensure that they will have the same rate constant if run at the same temperature? Explain. b)Two similar reactions have the same rate constant at 25 degrees Celsius, but at 35 degrees Celsius one of the reactions has a higher rate constant than the other. Account for these observations. 7. Consider the following equilibrium, for which Kp=0.0752 at 480 degrees Celsius: 2 Cl2(g) + 2 H2O(g)----> 4 HCl(g) + O2(g) <---- a) What is the value of Kp for the reaction 4 HCl(g) + O2(g)----> 2 Cl2(g) + 2 H2O(g)? <---- b) What is the value of Kp for the reaction Cl2(g) + H2O(g)-----> 2 HCl(g) + 1/2 O2(g)? <---- c) What is the value of Kc for the reaction in part b? 8. Phosphorous trichloride gas and chlorine gas react to form phosphorous pentachloride gas: PCl3(g)+ Cl2(g)-----> PCl5(g) <---- A 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 PpCl3= 0.124 atm, PCl2= 0.157atm, and PpCl5= 1.30atm. a) What is the value of Kp at this temperature? b) Does the equilibrium favor reactants or products? 9. Kp for the equilibrium N2(g) + 3 H2(g)----->2 NH3(g) <---- is 4.51 x 10^-5 at 450 degrees Celsius. For each of the mixtures listed below, indicate whether the mixture is at equilibrium at 450 degrees Celsius. If it is not at equilibrium, indicate the direction (toward product or toward reactants) in which the mixture must shift to achieve equilibrium. a) 105atm NH3, 35atm N2, 495atm H2 b) 35atm NH3, 595atm H2, no N2 c) 26atm NH3, 42atm H2, 202atm N2 10. Methanol (CH3OH) can be made by the reaction of CO with H2: CO(g) + 2 H2(g)----> CH3OH(g) <---- a) Use thermochemical data to calculate H for th