Ap Chemistry Unit 5 Progress Check |27 Questions| With Correct Answers.

Which of the following best describes the elementary step(s) in the reaction mechanism represented in the diagram above? {Ans: Two steps: Step 1: 2X(g)→X2(g) Step 2: X2(g)+Y(g)→X2Y(g)}The diagram above shows the reaction energy profiles for a reaction with and without a catalyst. Which of the following identifies the reaction energy profile for the catalyzed reaction, and why? {Ans: Profile Y, because it introduces a different reaction path that reduces the activation energy.}2NH3(g)−→−−−−catalystN2(g)+3H2(g) The catalyzed decomposition of NH3(g) at high temperature is represented by the equation above. The rate of disappearance of NH3(g) was measured over time for two different initial concentrations of NH3(g) at a constant temperature. The data are plotted in the graph below. On the basis of the data in the graph, which of the following best represents the rate law for the catalyzed decomposition of NH3(g)? {Ans: rate=k}Reaction A: O+O→O2 Reaction B: C2H4+C2H4→C4H8 Reaction C: CO+O2→CO2+O Reaction D: CH3I+Br−→CH3Br+I− {Ans: Reaction A, because the electron clouds of the O atoms are distributed symmetrically.}The two diagrams above represent collisions that take place at the same temperature between a CO molecule and an NO2 molecule. The products are CO2 and NO. Which diagram most likely