Chemistry: The Molecular Nature of Matter and Change 7th Edition

Published by McGraw-Hill Education
ISBN 10: 007351117X
ISBN 13: 978-0-07351-117-7

Chapter 19 - Problems: 19.23

Answer

pH of buffer = 3.63

Work Step by Step

1 (A) Given : 1. pH of the buffer = 5.44 2. Ka of Acid (HPr) = 1.3 x 10^-5 2 (B) Formulae : 1. Henderson - Hasselbalch equation of a buffer : pH = pKa + log [base] / [acid] 2. pKa = -log(Ka) 3 (C) Solution : 1. pKa = -log (Ka) = -log (1.3 x 10^-5) = 4.88 .... (1) 2. pH = pKa + log [base] / [acid] 5.44 = 4.88 + log ([Pr-] / [HPr]) 0.56 = log ([Pr-] / [HPr]) [Pr-] / [HPr] = 10^(0.56) = 3.63 Hence, the component concentration ratio [Pr-] / [HPr] is equl to 3.63 4 (D) Answer : pH of buffer = 3.63
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.