Question

Be sure to answer all parts. The recommended procedure for preparing a very dilute solution is not to weigh out a very small mass or measure a very small volume of stock solution. Instead, it is done by a series of dilutions. A sample of 0.7139 g of KMnO4 was dissolved in water and made up to the volume in a 500.0−mL volumetric flask. A 2.000−mL sample of this solution was transferred to a 1000−mL volumetric flask and diluted to the mark with water. Next, 10.00 mL of the diluted solution was transferred to a 250.0−mL flask and diluted to the mark with water. (a) Calculate the concentration (in molarity) of the final solution. Enter your answer in scientific notation. (b) Calculate the mass of KMnO4, needed to directly prepare the final solution. Enter your answer in scientific notation.