An overall reaction between nitric oxide and hydrogen is given as follows: 2NO + 2H2 → N2 + 2H;0 From experimental reaction testing data, you find the following empirical rate expression: IN, = K[NO] (H2] Two of your best engineers have proposed different mechanisms for the observed rate. (Part a) Show using the rate determining step approximation. Are either of the proposed mechanisms (or both) consistent with the empirical rate expression? (Part b) Are either (or both) of the mechanisms actually occurring? Explain. proposed mechanism 1: Step 1: 2NO + H2 > N2 + H2O2 (slow) k2 Step 2: H,O, + H, → 2H;0 (fast) proposed mechanism 2: ka Step 1: 2NO O N,O2 (fast) ka ks Step 2: N,O, + H; > N3 + H,O2 (slow) k2 Step 3: H2O2 + Hz > 2H20 (fast)

An overall reaction between nitric oxide and hydrogen is given as follows: 2NO + 2H2 → N2 + 2H;0 From experimental reaction testing data, you find the following empirical rate expression: IN, = K[NO] (H2] Two of your best engineers have proposed different mechanisms for the observed rate. (Part a) Show using the rate determining step approximation. Are either of the proposed mechanisms (or both) consistent with the empirical rate expression? (Part b) Are either (or both) of the mechanisms actually occurring? Explain. proposed mechanism 1: Step 1: 2NO + H2 > N2 + H2O2 (slow) k2 Step 2: H,O, + H, → 2H;0 (fast) proposed mechanism 2: ka Step 1: 2NO O N,O2 (fast) ka ks Step 2: N,O, + H; > N3 + H,O2 (slow) k2 Step 3: H2O2 + Hz > 2H20 (fast)

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter18: Chemical Kinetics

Section: Chapter Questions

Problem 5P

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In experiments on the decomposition of azomethane. CH3NHCH3(g)C2H6(g)+N2(g) the following data were obtained: Initial Concentration of Azomethane Initial Rate Exp. 1 1.13 102 M 2.8 106 M/s Exp. 2 2.26 102 M 5.6 106 M/s What is the rate law? What is the value of the rate constant?