A phosphate buffer solution containing 0.25 M KH2PO4 and 0.45 M K2HPO4 has a pH of 7.46. A small amount of HCl(aq) is added such that the initial concentrations: [H3O*], [H2PO4 ], and [HPO42-] are 0.060 M, 0.25 M, and 0.45 M, respectively. What is the final pH of the solution when the following buffering reaction occurred completely? (H2PO4 (aq) has Ka = 6.2 x 10-8) H3o*(aq) + HPO42-(aq) - H2PO4 (aq) + H20(1) (A) 6.24 (B) 7.21 (C) 7.31 (D) 7.64

A phosphate buffer solution containing 0.25 M KH2PO4 and 0.45 M K2HPO4 has a pH of 7.46. A small amount of HCl(aq) is added such that the initial concentrations: [H3O], [H2PO4 ], and [HPO42-] are 0.060 M, 0.25 M, and 0.45 M, respectively. What is the final pH of the solution when the following buffering reaction occurred completely? (H2PO4 (aq) has Ka = 6.2 x 10-8) H3o(aq) + HPO42-(aq) - H2PO4 (aq) + H20(1) (A) 6.24 (B) 7.21 (C) 7.31 (D) 7.64

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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