Question

Use the Henderson-Hasselbalch equation to calculate the mass of solid sodium acetate required to mix with 50.0 mL of 0.10 M acetic acid to prepare a pH 4 buffer. Ka for acetic acid is 1.8 times 10^-5. Use the Henderson-Hasselbalch equation to calculate the mass of solid ammonium chloride required to mix with 50.0 mL of 0.10 M ammonia to prepare a pH 10 buffer. The Kb for ammonia is 1.8 times 10^-5. The purpose of this experiment is to explore the concept of equilibria in the context of acids and bases, to understand the nature of acid-base equilibrium, buffer solutions, and pH. As with all experiments, you will be working in a potentially hazardous environment and must obey all lab safety rules. Hydrochloric acid, acetic acid, and sodium hydroxide are corrosive and will cause burns if spilled on skin or inhaled. This experiment does not generate any hazardous waste. The solutions will be collected for pretreatment by your instructor. To perform this experiment, you will need the following:

Answer 1

POH: 14-PH = 14-10, 4 4 : 4.74 + log [4H23 [0-107 4-4.74- .. log Co 1o 0-74 Lo.10] 0.74 I0 N H 0.018197 4 0.018197 mol NH4 4 CL 0.05K x 53.4 I mo 1 Mass ซู่ AVI 4 CL 0.048669 g.

Solu tion Henderson Hasselbach Eguation; base AcidJ Pkalog Kalog Cx 0) 474 8X10 [b a seJ 4 = 4.74 + log LbaseJ o.10] 4-4.74 0g -0.74 log Co.1o] 0-74 10 [0.10 0.18197 To 10 0.18197 x 0.1o CH3 302 -018197 m ol (mol Ma th 02 0.05k 82.04 Mass Na C2 H3 0