A 20 mL aliquot of skimmed milk was placed in an Erlenmeyer flask. To the flask was added 3 to 4 drops of phenolphthalein. The sample was titrated in triplicate using a previously standardized NaOH solution of 0.101 N concentration. The volumes of NaOH spent in the three experiments to reach chemical equivalence were: Volumes #1 = 3.50 mL #2 = 3.60 mL # 3 = 3.43 mL A control sample of 1.6 g/L of lactic acid was also analyzed in triplicate, the spent volumes of NaOH were: Volumes #1 = 3.41 mL #2 = 3.42 mL # 3 = 3.43 mL Find the acidity of the milk expressed in g/L of lactic acid. Write the neutralization reaction that occurs in the titration process.

A 20 mL aliquot of skimmed milk was placed in an Erlenmeyer flask. To the flask was added 3 to 4 drops of phenolphthalein. The sample was titrated in triplicate using a previously standardized NaOH solution of 0.101 N concentration. The volumes of NaOH spent in the three experiments to reach chemical equivalence were: Volumes #1 = 3.50 mL #2 = 3.60 mL # 3 = 3.43 mL A control sample of 1.6 g/L of lactic acid was also analyzed in triplicate, the spent volumes of NaOH were: Volumes #1 = 3.41 mL #2 = 3.42 mL # 3 = 3.43 mL Find the acidity of the milk expressed in g/L of lactic acid. Write the neutralization reaction that occurs in the titration process.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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