The following three step mechanism has been proposed for the oxidation of iodide ion by peroxide:

H2o2 + I^- ----> HOI + OH^- Slow
OH^- + H^+ ----> H2O Fast
HOI + H^+ + I^+ ---> I2 + H2O Fast

A. What is the overall reaction described by this mechanism?

B. What is the differential (basic) rate law predicted by this mechanism?

A. To determine the overall reaction described by this mechanism, we need to sum up the individual reactions and cancel out any common species. Let's take a look:

1. H2O2 + I^- → HOI + OH^- (Slow)
2. OH^- + H^+ → H2O (Fast)
3. HOI + H^+ + I^+ → I2 + H2O (Fast)

By canceling out the common species, we can simplify the overall reaction:

1. H2O2 + 2I^- + 2H^+ → I2 + 2H2O

Therefore, the overall reaction described by this mechanism is H2O2 + 2I^- + 2H^+ → I2 + 2H2O.

B. The differential (basic) rate law predicted by this mechanism can be determined by looking at the individual steps of the mechanism and identifying the rate-determining step. The rate-determining step is usually the slowest step in the mechanism and thus governs the overall rate of the reaction.

In this case, the rate-determining step is the first step, which is the slowest step. The rate of the overall reaction can be described by the rate of this step. From the stoichiometry of the first step, we can see that the rate of the reaction is directly proportional to the concentrations of H2O2 and I^-:

Rate = k[H2O2][I^-]

Note that the concentration of OH^- does not appear in the rate law because it is a fast step and is not involved in the rate-determining step.

Therefore, the differential (basic) rate law predicted by this mechanism is Rate = k[H2O2][I^-].

A. The overall reaction described by this mechanism is:

2 H2O2 + 2 I^- + 2 H^+ ---> 2 I2 + 4 H2O

B. The differential (basic) rate law predicted by this mechanism can be determined by examining the rate-determining step, which is the slowest step in the mechanism. In this case, the slowest step is the first step:

H2O2 + I^- ---> HOI + OH^-

Since the rate of the overall reaction is determined by the rate of this first step, the rate law can be written as:

Rate = k[H2O2][I^-]

Where k is the rate constant and [H2O2] and [I^-] are the concentrations of hydrogen peroxide and iodide ions, respectively.

HOI(aq) + H+ (aq)+ I-(aq) → I2(aq)+ H2O(l)