The oxidation of iodide ions by arsenic acid in aqueous solution occurs according to the reaction equation shown below:
Solution: The order with respect to each reactant can be found in the rate law as the power of the reactant.
For example, Rate= k[A]^2 is second order with respect to A.
Now, let's go back to our problem. Since I- is to the power of 1 in the rate law given, Choice A must be the correct answer choice.