Suppose you have an aqueous solution prepared by dissolving 0.051 mol of NaH2PO4 in 1 L of water (pK, (H2P04¯) = 7.21). This solution is not a buffer, but suppose you want to make it into one. How many moles of solid NaH2 PO4 must you add to this aqueous solution to make it into: a. A buffer of pH 7.21 n = mol b. A buffer of pH 6.21 mol c. A buffer of pH 8.21 n = mol

Suppose you have an aqueous solution prepared by dissolving 0.051 mol of NaH2PO4 in 1 L of water (pK, (H2P04¯) = 7.21). This solution is not a buffer, but suppose you want to make it into one. How many moles of solid NaH2 PO4 must you add to this aqueous solution to make it into: a. A buffer of pH 7.21 n = mol b. A buffer of pH 6.21 mol c. A buffer of pH 8.21 n = mol

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter15: Additional Aqueous Equilibria

Section: Chapter Questions

Problem 93QRT: When 40.00 mL of a weak monoprotic acid solution is titrated with 0.100-M NaOH, the equivalence...

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1) You are given a solution wherein [OH^-] is 1/4th of the concentration of [H^+]. What is the pH of this solution? 2)What is the change in pH when a few drops of strong base containing 3.0 x 10^-3moles of [OH^-] is added to a liter of either of the following two buffered solutions at pH6.4 (you can assume the volume remains approximately constant) i) a 250 mM solution of buffer A (pKa = 5.0) ii) a 250 mM solution of buffer B (pKa = 7.2) 3. Which solution is the more effective buffer at pH 6.40(provide a rationale for your answer)?