The ionization constant(s) and the molecular weight of a 0.542 g sample of unknown acid were determined by pH meter using Ag/AgCI as reference electrode. The unknown acid was titrated with 0.402 N NAOH and the results of the titration were tabulated below. Volume of N2OH (mL) Volume of pH Volume of pH PH NAOH (mL) NAOH (mL) 0.00 1.70 5.00 4.00 10.00 9.15 0.50 1.80 5.50 6.60 10.50 10.80 1.00 1.90 6.00 7.20 11.00 12.00 1.50 2.00 6.50 7.30 11.50 12.20 2.00 2.10 7.00 7.40 12.00 12.40 2.50 2.25 7.50 7.50 12.50 12.50 3.00 2.50 8.00 7.60 13.00 12.55 3.50 2.70 8.50 7.70 13.50 12.60 4.00 2.90 9.00 7.80 14.00 12.60 4.50 3.10 9.50 7.90 14.50 12.60 a. Using either a graphing paper, Microsoft Excel or any spreadsheet software, sketch the experimental titration curve graph b. Calculate the ionization constant(s). c. Calculate the molecular weight and equivalent weight of the unknown acid.

The ionization constant(s) and the molecular weight of a 0.542 g sample of unknown acid were determined by pH meter using Ag/AgCI as reference electrode. The unknown acid was titrated with 0.402 N NAOH and the results of the titration were tabulated below. Volume of N2OH (mL) Volume of pH Volume of pH PH NAOH (mL) NAOH (mL) 0.00 1.70 5.00 4.00 10.00 9.15 0.50 1.80 5.50 6.60 10.50 10.80 1.00 1.90 6.00 7.20 11.00 12.00 1.50 2.00 6.50 7.30 11.50 12.20 2.00 2.10 7.00 7.40 12.00 12.40 2.50 2.25 7.50 7.50 12.50 12.50 3.00 2.50 8.00 7.60 13.00 12.55 3.50 2.70 8.50 7.70 13.50 12.60 4.00 2.90 9.00 7.80 14.00 12.60 4.50 3.10 9.50 7.90 14.50 12.60 a. Using either a graphing paper, Microsoft Excel or any spreadsheet software, sketch the experimental titration curve graph b. Calculate the ionization constant(s). c. Calculate the molecular weight and equivalent weight of the unknown acid.

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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