You will be provided with two stock solutions, A and B. Solution A contains iodate ions and solution B contains sulfite ions along with some acid and starch. Note the concentration of each stock solution on your data sheet. In preparing your reaction systems, always add water first, followed by solution B, then add solution A.
Calculate the total volume of each needed reagent needed and record it on your data sheet. Pour approximately that amount from the reagent bottle into an appropriate size beaker. If you accidentally take too much, offer the extra to another group to minimize waste. For water, use distilled water.
Use 5.00 and 10.00 mL graduated pipets to measure out the larger volumes and 1.00 mL graduated pipets to measure out smaller volumes. Use a small (<250mL) beaker as your reaction vessel. Always add acid to water, never the other way around otherwise it can spatter and result in injury.
As temperature changes affect reaction rates, you will want to minimize contact with the solutions. After combining water and solution B, begin stirring using a glass stirring rod while another group member quickly adds solution A. Make sure the stopwatch is started as soon as solution A is added. Time each reaction using the stopwatch and record the time in ink on your data sheet. Record the temperature of the room for the reactions.
For 2 runs, calculate the order of the reaction with respect to iodate n and show this calculation in detail. Assuming the order to be first or second, estimate the order with respect to iodate ion as the nearest integer number. Then repeat this process, using 2 different runs, to estimate the order with respect to bisulfite ion. Finally, show the calculation of a value for the rate constant, k, by substitution of the results of run 1 into your rate law, and propose a complete rate law for this reaction.
