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14.99 The Rates of Reaction simulation (eChapter 14.2) allows you to adjust activation energy, overall energy change, temperature, and starting concentration of a reactant to assess the effect of each variable on initial reaction rate. (a) If you want to determine the rate law for the reaction using a series of experiments, which variable(s) must you vary, which variable(s) should you not vary, and for which variable(s) does it not make any difference? (b) Determine the rate law for the reaction. What is the overall order of the reaction? (c) Determine the value of the rate constant.

14.100 (a) Using data from the Rates of Reaction simulation (eChapter 14.2) , select a temperature (T₁) and an activation energy (E_a) and determine the value of the rate constant (k₁) (b) Using the E_a and (T₁) from part (a), predict the value of the rate constant (k₂) at a higher temperature, T₁ = 2T₁. (c) Again using E_a from part (a) and the temperature from either part (a) or part (b), predict the value of the rate constant (k₃) at a temperature (T₃) that is lower than T₁. Use the simulation to check your answers for parts (a), (b), and (c).

14.101 The First-Order Process movie (eChapter 14.3) illustrates the change in concentration over time for a process that is first order overall. (a) Determine the rate constant for the process shown. (b) Assuming that the first-order process is a chemical reaction, what would normally happen to the value of the half-life if the temperature were increased? (c) Many enzyme-catalyzed reactions are first order in the concentration of substrate. However, increasing the temperature does not always increase the rate. Why might this be so?

14.102 Using the numerical value of the rate constant you calculated for the reaction in the previous question and using the same "unit" concentration as in the First-Order Process movie (eChapter 14.3), generate a curve for a second-order reaction with Equation 14.16. Reproduce the first-order curve, superimpose the second-order curve onto it, and compare them. What can you say about the relative rates of disappearance of the starting material initially and after a significant period of time has passed?

14.103 In Exercise 14.69, you explained why the combination of ethylene and D₂ in the presence of a catalyst predominantly produces CH₂D—CH₂D. A small amount of product has more than one D bound to a carbon, as in CH₂D—CHD₂. After watching the Surface Reaction-Hydrogenation movie (eChapter 14.6), propose a mechanism by which product with more than one D per carbon atom could arise.