Given the values of K and Kb below, which of the systems given would be most suitable to use to construct a buffer of pH 97HCOOH, K, = 1.8 x 104CH3COOH, K3=18x105H3ASO4. Ka1 = 6.0 x 10, Ka2 = 1.1 x 10, Ka3 = 3 x 1012C5H5N, Kp = 1,7x10-9NH3 КЬ - 1.3 х. 10-5OA H3ASO4/NaH2As04eB. HCOOH/NAHCOOOC. C5H5N/ C5H5NHCIOD.CH3COOH/KCH3CO0FOE NH4C/NH3

The pH of a buffer solution remain close to the pKa value of its acid in weak acid / base and its conjugate pair. Among the given solution Kb of NH3 = 1.8 x 10^-5 Thus pKb = -log Kb = -log (1.8 x 10^-5) = 4.75 pKa + pKb = 14 pKa of conjugate acid of NH3 , NH4+ will be = 14 - pKb = 14 - 4.75 = 9.25 Thus to prepare the buffer solution with pH 9 the suitable acid base pair will be NH4Cl / NH3 Answer : Option E

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Given the values of Ka and Kh below, which of the systems given would be most suitable to use to construct a buffer of pH 9? HCOOH, Ka = 1.8 x 104 CH3COOH, Ka = 1.8 x 10-5 H3ASO4. Ka1 = 6.0 x 103, Ka2 = 1.1 x 107, Ka3 = 3 x 1o-12 CSH5N, Kb = 1.7 x 10-9 NH3, Кь - 1.8 х 10-5 O A. H3ASO4/NaH2AsO4 O B. HCOOH/NAHCOO O C. C5H5N/ C5H5NHCI O D. CH3COOH/KCH3COO E. NH4CI/NH3

Given the values of Ka and Kh below, which of the systems given would be most suitable to use to construct a buffer of pH 9? HCOOH, Ka = 1.8 x 104 CH3COOH, Ka = 1.8 x 10-5 H3ASO4. Ka1 = 6.0 x 103, Ka2 = 1.1 x 107, Ka3 = 3 x 1o-12 CSH5N, Kb = 1.7 x 10-9 NH3, Кь - 1.8 х 10-5 O A. H3ASO4/NaH2AsO4 O B. HCOOH/NAHCOO O C. C5H5N/ C5H5NHCI O D. CH3COOH/KCH3COO E. NH4CI/NH3

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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