2) The following experimental process steps have been made to determine the hardness of water. Accordingly, 100 mL sample was acidified with a few drops of 6 M HCl and boiled for a while to remove the CO2 in it. Then, a few drops of methyl red (pH: 4.2-6.3) were added to the cooled sample and the solution was neutralized with 0.1M NaOH, then 2 mL of 0.01M pH10 buffer and 4-5 drops of EBT indicator were added and the solution was 0.0086M. It was titrated with EDTA until the color turned blue. Since the consumption of titrant is 11.44mL, calculate the amount of Ca in the water in terms of mg CaCO3. (Ca: 40, C: 12, 0: 16)

2) The following experimental process steps have been made to determine the hardness of water. Accordingly, 100 mL sample was acidified with a few drops of 6 M HCl and boiled for a while to remove the CO2 in it. Then, a few drops of methyl red (pH: 4.2-6.3) were added to the cooled sample and the solution was neutralized with 0.1M NaOH, then 2 mL of 0.01M pH10 buffer and 4-5 drops of EBT indicator were added and the solution was 0.0086M. It was titrated with EDTA until the color turned blue. Since the consumption of titrant is 11.44mL, calculate the amount of Ca in the water in terms of mg CaCO3. (Ca: 40, C: 12, 0: 16)

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter14: Principles Of Neutralization Titrations

Section: Chapter Questions

Problem 14.9QAP

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