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.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.33QAP

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