Consider the proposed mechanism. What is its overall reaction? Step 1: N2O5 ⇋ NO2 + NO3 (fast) Step 2: NO2 + NO3 → NO + NO2 + O2 (slow) Step 3: NO + NO3 → 2 NO2 (fast)

NO(g) and O2(g) react to form NO2(g). The rate law of the reaction is rate=k[NO]2[O2]. If the reaction occurs in a single elementary step that is a three-body molecular collision, then which of the following is the equation for the elementary step? a.) N+O+O→NO2 b.) 2NO+O2→2NO2 c.) N+O2→NO2 d.) N2+2O2→2NO2

MISSED THIS? Watch KCV: Reaction Mechanisms, IWE: Reaction Mechanisms; Read Section 15.6. You can click on the Review link to access the section in your e Text. Consider this three-step mechanism for a reaction: k₁ Cl₂(g) k₂ Cl(g) + CHCl3 (g) → k3 Cl(g) + CC13 (g) → k4 2Cl(g) (fast) HCl(g) + CCl3(g) (slow) CCL (g) (fast) Part A What is the overall reaction? Express your answer as a chemical equation. Identify all of the phases in your answer. ► View Available Hint(s) 0 xa ΑΣΦ Xb a b 06 18 Cl,+Cl→HCl+CC1, A chemical reaction does not occur for this question. Submit Previous Answers Request Answer X Incorrect; Try Again; 3 attempts remaining 冈 ? www

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Given the following proposed mechanism, predict the rate law for the overall reaction: 2 NO2 + Cl2 step 1: NO2 + Cl2 - step 2: NO2 + CI → 2 NO2CI NO2CI + CI NO2CI overall slow fast O A. rate = k[NO2CI][CI] O B. rate = k[NO21?[Cl2] O C. rate = k[NO2][Cl2] OD. rate = k[NO2C1]2 %3D O E. rate = k[NO2][C]]

10. The experimental rate law for the decomposition of nitrous oxide (N₂O) to N₂ and O₂ is Rate = k[N₂O]2. Two mechanisms are proposed: I. NO → N,+0 → +O NO+0→ N2+O2 II. 2N₂O 2N₂0 N4O₂ N4O₂ → 2N₂ + O₂ Which of the following could be a correct mechanism? A) Mechanism I with the first step as the rate-determining step. B) Mechanism I with the second step as the rate-determining step. C) Mechanism II with the second step as the rate-determining step. D) Two of these could be correct. E) None of these could be correct.

Plot six data points, one for each minute, to show how the concentration of the reactant X changes during the reaction shown below. The reactant is completely consumed in 5 minutes. The consumption of X is second order. X+B Y 100 A t = 0 min 90 B t=1 min 80 о O 70 60 要 50 40 30 20 10 t=2min Dt=3min Time (min) 8 C E t=4 min t = 5 min

The conversion of cyclopropane to propene in the gas phase is a first-order reaction with a rate constant of 6.7 x 1024 s-1 at 500°C.   a. If the initial concentration of cyclopropane was 0.25 M, what is the concentration after 8.8 min?   b. How long (in minutes) will it take for the concentration of cyclopropane to decrease from 0.25 M to 0.15 M?   c. How long (in minutes) will it take to convert 74 percent of the starting material?

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6. For the reaction H2(g) +2 ICl(g) →2 HCl(g) + I2(g) one proposed mechanism is H2(g) + ICl(g) → HICl(g) + H(g) slow H(g) ICl(g) → HCl(g) + I(g) + fast HICl(g) → HCl(g) + I(g) fast I(g) + I(g) → I2(g) fast Intermediates in this reaction include which of the following? (A) HICI only (B) I only (C) HICI and H only (D) HICI, H, and I