Consider the reaction NO2(g) + CO(g) → NO(g) + CO2(g) The mechanism it is thought to the follow is: Step 1: NO2(g) + NO2(g) → NO3(g) + NO(g) Step 2: NO3(g) + CO(g) → NO2(g) + CO2(g) Which of the following species is an intermediate?

A chemistry graduate student is studying the rate of this reaction: 2N₂O5 (g) 2N₂O4 (g) +O₂ (g) He fills a reaction vessel with N₂O5 and measures its concentration as the reaction proceeds: 2 time (seconds) 0 0.10 [N₂05] 0.0200M 0.40 0.0132M 0.20 0.00865 M 0.30 0.00569 M 0.00374 M Use this data to answer the following questions. Write the rate law for this reaction. Calculate the value of the rate constant k. Round your answer to 2 significant digits. Also be sure your answer has the correct unit symbol. rate = k k = 0 x10 × S

Considering the reaction: 4 PH3(g)  →  P4(g)  + 6 H2(g) Which of the following statements is TRUE? Considering the reaction: 4 PH3(g)  →  P4(g)  + 6 H2(g) Which of the following statements is TRUE? The rate of appearance of H2 is six times the rate of appearance of P4. The rate of appearance of P4 is six times the rate of disappearance of PH3. The rate of appearance of P4 is six times the rate of appearance of H2. The rate of disappearance of PH3 is six times the rate of appearance of P4.

e The reaction of NO₂ (g) and CO(g) is thought to occur in two steps: Step 1 Slow NO2(g) + NO₂(g) → NO(g) + NO3 (9) Step 2 Fast NO3 (9) + CO(g) → NO2 (g) + CO2 (9) What species is an intermediate in this reaction?

HCl can be produced by the exothermic reaction H2(g)+2ICl(g)→2HCl(g)+I2(g) . A proposed mechanism for the reaction has two elementary steps as shown below. Step 1: H2(g)+ICl(g)→HI(g)+HCl(g) (slow) Step 2: HI(g)+ICl(g)→HCl(g)+I2(g) (fast) Draw an energy diagram with a curve that shows the following two details. (1) The relative activation energies of the two elementary steps and (2) the enthalpy change of the overall reaction

NO2(g) + CO(g)  NO(g) + CO2(g) The rate of the above reaction depends only on the concentration of nitrogen dioxide at temperatures below 225°C.At a temperature below 225°C the following data were obtained:  Time(s)  [NO2](mol/L) 0 0.740 1.60×103 0.663 4.00×103 0.574 6.00×103 0.516 1.20×104 0.396 2.40×104 0.270 Which of the following expressions for the rate law (either differential or integrated) are completely consistent with the above experimental data.     [NO2] - [NO2]0 = -kt    [NO2] = 1/(kt + 1/[NO2]0)    k[NO2]2 = d[CO2]/dt    d[CO2]/dt = k[NO2]    -d[NO2]/dt = k[NO2]2   write YES beside the equations that are consistent with the data and NO beside the ones that arent consistent with the data.

Consider these three reactions as the elementary steps in the mechanism for a chemical reaction. (i) H2(g) + NO(g) à H2O(g) + N(g) Ea = 436 kJ ∆H = –491 kJ (ii) N(g) + NO(g) à N2(g) + O(g) Ea = 625 kJ ∆H = –312 kJ (iii) O(g) + H2(g) à H2O(g) Ea = 1690 kJ ∆H = +131 kJ Draw the potential energy diagram for the reaction. Assume the potential energy of the reactants was 1400 kJ

X, + Y2 - X,Y2 rate = K[X,] A reaction and its experimentally determined rate law are represented above. A chemist proposes two different possible mechanisms for the reaction, which are given below. Mechanism 1 X, - 2 X (slow) X + Y, - XY, (fast) Mechanism 2 X, -- 2 X (slow) X + Y2 + XY + Y (fast) X + XY, - X,Y, (fast) X+ XY -- X,Y (fast) X,Y + Y → X,Y, (fast) Based on the information above, which of the following is true? Both mechanism 1 and mechanism 2 are consistent with the rate law. Only mechanism 2 is consistent with the rate law. Only mechanism 1 is consistent with the rate law. Neither mechanism 1 nor mechanism 2 is consistent with the rate law.

A chemistry graduate student is studying the rate of this reaction: 2H₂PO4 (aq) → P₂O₂ (aq) + 3H₂O (aq) He fills a reaction vessel with H₂PO4 and measures its concentration as the reaction proceeds: time (seconds) [H₂PO4] 0 0.700M 10. 0.273 M 20. 0.170M 30. 0.123 M 40. 0.0967M Use this data to answer the following questions. Write the rate law for this reaction. x10 Calculate the value of the rate constant k. Round your answer to 2 significant digits. Also be sure your answer has the correct unit symbol. X rate = k k = 0 ?

Ozone decomposes to oxygen gas. 2O3(g) → 3O2(g) A proposed mechanism for this decomposition is O3 K1⇌ k O2+O  (fast, equilibrium) O3+O → 2O2   (slow) What is the rate law derived from this mechanism?