The hydrogenation of acetylene (C2H2) on Pd metal sites (*) is proposed to occur via elementary steps consisting of: 1) QE dissociative adsorption of H2: 2) QE molecular adsorption of C2H2; 3) & 4) QE sequential addition of H" to form C:Ha"; 5) Irreversible desorption of ethylene. Write the mechanism of the reaction with the stoichiometric number of each step. Derive the rate expression in terms of constants and measurable quantities when C:H," and " are the MARI. If C;H, is in the MARI expression, why is the rate independent of the concentration of C¿H4 in the gas phase? At some conditions, the experimental rate is zero order in both CH2 and H2. What additional assumption(s) are required for this observation to be consistent with the rate expression derived in part (b)? 1) If, under certain experimental conditions, an effective zero order rate constant is measured, explain the chemical significance of this constant (in terms of rate or equilibrium constants for elementary steps) using the rate expression in part (b).

The hydrogenation of acetylene (C2H2) on Pd metal sites (*) is proposed to occur via elementary steps consisting of: 1) QE dissociative adsorption of H2: 2) QE molecular adsorption of C2H2; 3) & 4) QE sequential addition of H" to form C:Ha"; 5) Irreversible desorption of ethylene. Write the mechanism of the reaction with the stoichiometric number of each step. Derive the rate expression in terms of constants and measurable quantities when C:H," and " are the MARI. If C;H, is in the MARI expression, why is the rate independent of the concentration of C¿H4 in the gas phase? At some conditions, the experimental rate is zero order in both CH2 and H2. What additional assumption(s) are required for this observation to be consistent with the rate expression derived in part (b)? 1) If, under certain experimental conditions, an effective zero order rate constant is measured, explain the chemical significance of this constant (in terms of rate or equilibrium constants for elementary steps) using the rate expression in part (b).

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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