A buffer is to be prepared from acetic acid (CH3COOH) and sodium acetate(NACH3COO). What ratio of NaCH3COO to CH3COOH must be used to prepare abuffer with a pH of 6.74?Useful information:Ka for CH3COOH is 1.82 x 105pH = pK, + log ([Base]/[Acid])%3!O 2:1100:1O 1:100O 1:2

Correct answer is 100 : 1. pka = -log ka = -log ( 1.82 x 10-5 ) = 5 - 0.26 = 4.74 Henderson equation…

A buffer is to be prepared from acetic acid (CH3COOH) and sodium acetate (NACH3COO). What ratio of NACH3CO0 to CH3COOH must be used to prepare a buffer with a pH of 6.74? Useful information: Ka for CH3COOH is 1.82 x 105 • pH = pK, + log ([Base]/[Acid)) O 2:1 O 100:1 O 1:100 O 1:2

A buffer is to be prepared from acetic acid (CH3COOH) and sodium acetate (NACH3COO). What ratio of NACH3CO0 to CH3COOH must be used to prepare a buffer with a pH of 6.74? Useful information: Ka for CH3COOH is 1.82 x 105 • pH = pK, + log ([Base]/[Acid)) O 2:1 O 100:1 O 1:100 O 1:2

Chemistry: Principles and Reactions

8th Edition

ISBN:9781305079373

Author:William L. Masterton, Cecile N. Hurley

Publisher:William L. Masterton, Cecile N. Hurley

Chapter14: Equilibria In Acid-base Solutions

Section: Chapter Questions

Problem 33QAP: A buffer is prepared in which the ratio [ H2PO4 ]/[ HPO42 ]is 3.0. (a) What is the pH of this...

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