You wish to prepare 1 L of a 0.02-M potassium iodate solution. You require that the final concentration be within 1% of 0.02 M and that the concentration must be known accurately to the fourth decimal place. How would you prepare this solution? Specify the glassware you would use, the accuracy needed for the balance, and the ranges of acceptable masses of \(\mathrm{KIO}_{3}\) that can be used

Firstly, we need to find out the target mass of KIO3 required to make a 1 L solution with a concentration of 0.02 M. We will use the following formula: \[mass = (m p ) á (V) á (M)\] where: \(mass\) = mass of KIO3 in grams \(MW\) = molecular weight of KIO3 \(V\) = volume of the solution in liters \(M\) = molarity of the solution in moles/liter The molecular weight of KIO3 is 166 g/mol (39 g/mol from potassium, 127 g/mol from iodine, and 16x3 g/mol from oxygen). The volume and molarity of the solution are 1 L and 0.02 M, respectively. Plugging in the values into the formula, we find: \(mass = (166 g \cdot mol^{-1}) á (1 L) á (0.02 mol \cdot L^{-1}) = 3.32 g\)

Next, we will determine the acceptable range of KIO3 masses that will result in a concentration within 1% of the desired 0.02 M. To find the upper and lower bounds of the acceptable mass range, we will multiply the target mass (3.32 g) by 1.01 and 0.99, respectively: Upper bound mass = \(3.32 g × 1.01 = 3.35 g\) Lower bound mass = \(3.32 g × 0.99 = 3.29 g\) Hence, the acceptable mass range of KIO3 needed for this solution is between 3.29 g and 3.35 g.

To ensure the high level of accuracy needed for the final concentration, we should use high-quality glassware and devices. For the glassware, we can use a volumetric flask that is rated to hold 1 L of solution and has a high uncertainty tolerance to ensure precise volumes. A 1 L Class A volumetric flask would be suitable for this purpose, as it has an uncertainty of ± 0.1 mL in volume, which is sufficient for a four decimal place accuracy in the final concentration. As for the balance, we will need to choose one with a high level of precision and accuracy. Since we need to measure an acceptable mass range of 3.29 g to 3.35 g, a balance with a readability of 0.0001 g (0.1 mg) would be suitable. This level of precision will allow us to obtain the required four decimal place accuracy in the final concentration.

Finally, we will weigh out the KIO3 and prepare the solution using the recommended glassware and balance. 1. Use the high-precision balance (0.0001 g readability) to weigh out a mass of KIO3 between the acceptable range of 3.29 g to 3.35 g. 2. Dissolve the KIO3 in a small volume of distilled water in a beaker. 3. Transfer the dissolved KIO3 solution into the 1 L Class A volumetric flask. 4. Rinse the beaker with distilled water and add the rinsate to the volumetric flask to ensure complete transfer. 5. Fill the volumetric flask with distilled water up to the 1 L mark. 6. Mix the solution well by gently inverting the flask several times to distribute the KIO3 evenly throughout the solution. Now you have prepared a 1 L solution with a potassium iodate concentration within 1% of 0.02 M, known accurately to the fourth decimal place. Keep in mind that the range is calculated to assess the accuracy needs and may be different from the analytical needs of the experiment.