(Incorrect) In order to prepare very dilute solutions, a lab technician chooses to perform a series of dilutions instead of measuring a very small mass. A solution was prepared by dissolving 0.360 g of KNO3 in enough water to make 500. mL of solution. A 10.0 mL sample of this solution was transferred to a 500.0-mL volumetric flask and diluted to the mark with water. Then 10.0 mL of the diluted solution was transferred to a 250.0-ml flask and diluted to the mark with water. What is the final concentration of the KNO3 solution? 7.12 × 103 M (Your answer) 2.85 x 10-6 M 7.91 × 10-⁹ M 5.70 x 10-6 M (Correct answer) 1.42 × 10-¹4 M

(Incorrect) In order to prepare very dilute solutions, a lab technician chooses to perform a series of dilutions instead of measuring a very small mass. A solution was prepared by dissolving 0.360 g of KNO3 in enough water to make 500. mL of solution. A 10.0 mL sample of this solution was transferred to a 500.0-mL volumetric flask and diluted to the mark with water. Then 10.0 mL of the diluted solution was transferred to a 250.0-ml flask and diluted to the mark with water. What is the final concentration of the KNO3 solution? 7.12 × 103 M (Your answer) 2.85 x 10-6 M 7.91 × 10-⁹ M 5.70 x 10-6 M (Correct answer) 1.42 × 10-¹4 M

Introductory Chemistry: A Foundation

9th Edition

ISBN:9781337399425

Author:Steven S. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Donald J. DeCoste

Chapter15: Solutions

Section: Chapter Questions

Problem 39QAP: 39. Standard solutions of calcium ion used to test for water hardness are prepared by dissolving...

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