An eggshell is treated with NaOH to remove the membrane, dried and found to weigh 5.131 g. The shell is then dissolved in 25 mL of 6M HCI, filtered and diluted with distilled water to 250 mL in a volumetric flask. A 10.00 mL aliquot is buffered to pH 10 and titrated with 0.04916 M EDTA. If 40.78 mL is required to reach the Eriochrome black T endpoint signal, calculate the percentage of: (a) Ca, (b) CaCO3 in the eggshell.

An eggshell is treated with NaOH to remove the membrane, dried and found to weigh 5.131 g. The shell is then dissolved in 25 mL of 6M HCI, filtered and diluted with distilled water to 250 mL in a volumetric flask. A 10.00 mL aliquot is buffered to pH 10 and titrated with 0.04916 M EDTA. If 40.78 mL is required to reach the Eriochrome black T endpoint signal, calculate the percentage of: (a) Ca, (b) CaCO3 in the eggshell.

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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