A biology experiment requires the use of a nutrient fluid buffered at a pH of 4.85, and 659 mL of the solution is needed. It has to be buffered to be able to hold the pH to within +0.10 pH units of 4.85 even if 5.00 x 103 mol of OH" or 5.00 x 103 mol of H* ion enter. Record all your answers to three (3) significant figures. Pick the best acid and its sodium salt that could be used to prepare the solution. O Hydrocyanic acid and sodium cyanide (pK = 9.21). O Nitrous acid and sodium nitrite (pK, = 3.15). • Acetic acid and sodium acetate (pK, = 4.74). O Hydrofluoric acid and sodium fluoride (pK, = 3.17). Hint Calculate the minimum number of grams of the acid and its sodium salt that are needed to prepare the buffer solution. Mass acid = Mass sodium salt = Hint Calculate the molar concentration of the acid and its sodium salt that are needed to prepare the buffer solution. Concentration acid = M Concentration sodium salt = M Hint

A biology experiment requires the use of a nutrient fluid buffered at a pH of 4.85, and 659 mL of the solution is needed. It has to be buffered to be able to hold the pH to within +0.10 pH units of 4.85 even if 5.00 x 103 mol of OH" or 5.00 x 103 mol of H* ion enter. Record all your answers to three (3) significant figures. Pick the best acid and its sodium salt that could be used to prepare the solution. O Hydrocyanic acid and sodium cyanide (pK = 9.21). O Nitrous acid and sodium nitrite (pK, = 3.15). • Acetic acid and sodium acetate (pK, = 4.74). O Hydrofluoric acid and sodium fluoride (pK, = 3.17). Hint Calculate the minimum number of grams of the acid and its sodium salt that are needed to prepare the buffer solution. Mass acid = Mass sodium salt = Hint Calculate the molar concentration of the acid and its sodium salt that are needed to prepare the buffer solution. Concentration acid = M Concentration sodium salt = M Hint

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter15: Acid–base Equilibria

Section: Chapter Questions

Problem 58P

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