Consider the following reaction mechanism. Changing the concentration of which substance(s) would have the most effect on the rate of the overall reaction? 2A --> B+ 2C (slow) B+C --> D + E (fast) C + D -> E+ F (fast)

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.

6. Given the reaction: CH3(CO)CH3 (M) | B(M) 0.010 0.010 CH3(CO)CH3 + I2 + H* → CH3(CO)CH2I + HI H* (M) Rate (M/s) 0.010 3.0 x 10-4 0.010 6.0 x 10-4 0.020 6.0 x 104 0.020 2.4 x 10-3 0.040 4.8 x 10-3 0.010 6.0 x 104 0.010 0.020 0.010 0.040 0.040 0.020 0.020 0.040 0.020 0.040 a. Determine the reaction order for each reactant. b. Solve for the rate constant, k, and the appropriate units. c. Write the rate law for the reaction, including a value for k. d. Solve for the rate of the reaction if there are 1.25 M of CH3(CO)CH3, 2.25 M of I2, and 3.25 M H*.

NTERACTIVE EXAMPLE Reaction Rate Chloromethane reacts with iodide ion to yield iodomethane and chloride ion. CH;C1 +r- CH;I + CF A way to determine the rate of the reaction of chloromethane with iodide ion is to measure the disappearance of T from the solution. Suppose that the concentration of I was 0.21 mol IL at the start of the reaction. At the end of 20 min, the concentration dropped to 0.13 mol L. This difference is equal to a change in concentration of -0.08 mol IL. QUESTION What is the rate of reaction with respect to iodide ion? |× molIL'min