3. You need to prepare 100 mL of a 0.200 M acetate buffer at pH 5.00. The pKa of acetic acid is 4.756 and the density of liquid acetic acid is 1.049 g/mL. You have pure liquid acetic acid (CH3CO2H; FW = 60.05 g/mol) and pure sodium acetate trihydrate (Na+CH3CO²- 3 H₂O; FW = 136.08 g/mol) available to you to prepare the buffer. a. Calculate the volume (in mL) of liquid acetic acid that must be added to the 100 mL volumetric flask. b. Calculate the mass (in grams) of sodium acetate that you would need to add to the 100 ml flask to prepare 100 mL of a pH 5.00 acetate buffer. c. If you only had the pure liquid acetic acid and 1.0 M NaOH available to you to prepare the buffer, what volume (in mL) of 1.0 M NaOH that must be added to what the volume (in mL) of liquid acetic acid to create the appropriate buffer?

3. You need to prepare 100 mL of a 0.200 M acetate buffer at pH 5.00. The pKa of acetic acid is 4.756 and the density of liquid acetic acid is 1.049 g/mL. You have pure liquid acetic acid (CH3CO2H; FW = 60.05 g/mol) and pure sodium acetate trihydrate (Na+CH3CO²- 3 H₂O; FW = 136.08 g/mol) available to you to prepare the buffer. a. Calculate the volume (in mL) of liquid acetic acid that must be added to the 100 mL volumetric flask. b. Calculate the mass (in grams) of sodium acetate that you would need to add to the 100 ml flask to prepare 100 mL of a pH 5.00 acetate buffer. c. If you only had the pure liquid acetic acid and 1.0 M NaOH available to you to prepare the buffer, what volume (in mL) of 1.0 M NaOH that must be added to what the volume (in mL) of liquid acetic acid to create the appropriate buffer?

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 25QAP: A sodium hydrogen carbonate-sodium carbonate buffer is to be prepared with a pH of 9.40. (a) What...

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A sodium hydrogen carbonate-sodium carbonate buffer is to be prepared with a pH of 9.40. (a) What must the [ HCO3 ]/[ CO32 ]ratio be? (b) How many moles of sodium hydrogen carbonate must be added to a liter of 0.225 M Na2CO3 to give this pH? (c) How many grams of sodium carbonate must be added to 475 mL of 0.336 M NaHCO3 to give this pH? (Assume no volume change.) (d) What volume of 0.200 M NaHCO3 must be added to 735 mL of a 0.139 M solution of Na2CO3 to give this pH? (Assume that volumes are additive.)
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