**Section 18.11: Calculating Alkalinity Using Acid-Base Titration**In this section, we explore the procedure for calculating the phenolphthalein and total alkalinity of water samples using titration:**Sample Analysis:**- **(a) 50-mL Sample:** - Required 5.3 mL of 0.020 N H₂SO₄ to reach the phenolphthalein end point. - Required a total of 15.2 mL to reach the methyl orange end point.- **(b) 100-mL Sample:** - Required 20.2 mL of 0.020 N H₂SO₄ to reach the phenolphthalein end point. - Required a total of 25.6 mL to reach the methyl orange end point.**Explanation:**In this analysis, titration involves adding a standard solution of sulfuric acid (H₂SO₄) to the water samples until specific pH indicators (phenolphthalein and methyl orange) signal the endpoints. The volumes of H₂SO₄ needed to reach these endpoints allow us to calculate the alkalinity of the samples in terms of their ability to neutralize acid.

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3.11 Calculate the phenolphthalein and total alkalinities of the following samples: (a) A 50-mL sample required 5.3 mL 0.020 N H₂SO4 to reach the phenolphthalein end point and a total of 15.2 mL to reach the methyl orange end point. (b) A 100-mL sample required 20.2 mL of 0.020 N H₂SO4 to reach the phenolphthalein end point and a total of 25.6 mL to reach the methyl orange end point

3.11 Calculate the phenolphthalein and total alkalinities of the following samples: (a) A 50-mL sample required 5.3 mL 0.020 N H₂SO4 to reach the phenolphthalein end point and a total of 15.2 mL to reach the methyl orange end point. (b) A 100-mL sample required 20.2 mL of 0.020 N H₂SO4 to reach the phenolphthalein end point and a total of 25.6 mL to reach the methyl orange end point

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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