A 100.0 mL buffer solution is constructed using 0.035 M HX, a weak acid, and 0.045 M NaX. Ka. HX = 4.7 x 10-6 a) Based on the Ka, what is the pH range where the buffer should be effective. b) From the given concentrations, what is the actual pH of the constructed buffer. c) What would the pH of the buffer if 0.0020 mol of HCI is added to the buffer solution. d) What would the pH be if 0.0020 mol of HCl was added to 100.0 mL of pure water without the presence of the buffer. Assume NaX and HCl completely dissociate.

A 100.0 mL buffer solution is constructed using 0.035 M HX, a weak acid, and 0.045 M NaX. Ka. HX = 4.7 x 10-6 a) Based on the Ka, what is the pH range where the buffer should be effective. b) From the given concentrations, what is the actual pH of the constructed buffer. c) What would the pH of the buffer if 0.0020 mol of HCI is added to the buffer solution. d) What would the pH be if 0.0020 mol of HCl was added to 100.0 mL of pure water without the presence of the buffer. Assume NaX and HCl completely dissociate.

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 14QAP: A buffer solution is prepared by adding 5.50 g of ammonium chloride and 0.0188 mol of ammonia to...

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