10 points Reference Chang 1326 8 The rate constant for the second order

# 10 points reference chang 1326 8 the rate constant

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(10 points)(Reference: Chang 13.26)8.The rate constant for the second-order reaction2NOBr(g)→ 2NO(g) + Br2(gis 0.80/M · s at 10ºC. a.Starting with a concentration of 0.086 M, calculate the concentration of NOBr after 22 s. (5 points)b.Calculate the half-lives when [NOBr]0= 0.072 Mand [NOBr]0= 0.054 M(5 points)(Reference: Chang 13.27)9.Define activation energy. What role does activation energy play in chemical kinetics? (5 points)(Reference: Chang 13.31)10. Given the same reactant concentrations, the reactionCO(g) + Cl2(g)→ COCl2(gat 250°C is 1.50 × 103times as fast as the same reaction at 150°C. Calculate the activation energy for this reaction. Assume that the frequency factor is constant. ) . ) 3 Copyright © 2014 by Thomas Edison State College. All rights reserved.
(Hint: use equation 13.14.) (10 points) (Reference: Chang 13.38) 11. Most reactions, including enzyme-catalyzed reactions, proceed faster at higher temperatures. However, for a given enzyme, the rate drops off abruptly at a certain temperature. Account for this behavior. (5 points)(Reference: Chang 13.61)12. The bromination of acetone is acid-catalyzed:CH3COCH3+ Br2→ CH3COCH2Br+ H++ BrThe rate of disappearance of bromine was measured for several different concentrations of acetone, bromine, and H+ions at a certain temperature: [CH3COCH3][Br2][H+]Rate of Disappearance of Br2(M/s)(1)0.300.0500.0505.7 × 10–5(2)0.300.100.0505.7 × 10–5(3)0.300.0500.101.2 × 10–4(4)0.400.0500.203.1 × 10–4(5)0.400.0500.0507.6 × 10–5a.What is the rate law for the reaction? (5 points)b.Determine the rate constant. (5 points)(Reference: Chang 13.79)13. Briefly comment on the effect of a catalyst on each of the following: (a) activation energy, (b) reaction mechanism, (c) enthalpy of reaction, (d) rate of forward step, (e) rate of reverse step. (15 points) (Reference: Chang 13.91) 4 Copyright © 2014 by Thomas Edison State College. All rights reserved.