The concentration of a solution of EDTA was determined by standardizing against a solution of Ca2+ prepared from the primary standard CaCO3. A 0.4025 g sample of CaCO3 was transferred into a 250 mL Erlenmeyer flask and the pH adjusted by adding 5 mL of a pH 10 NH3-NH4Cl buffer containing a small amount of Mg2+EDTA. After adding calmagite as a visual indicator, the solution was titrated with the EDTA requiring 42.36 mL to reach the end point. Report the molar concentration of the titrant.

The concentration of a solution of EDTA was determined by standardizing against a solution of Ca2+ prepared from the primary standard CaCO3. A 0.4025 g sample of CaCO3 was transferred into a 250 mL Erlenmeyer flask and the pH adjusted by adding 5 mL of a pH 10 NH3-NH4Cl buffer containing a small amount of Mg2+EDTA. After adding calmagite as a visual indicator, the solution was titrated with the EDTA requiring 42.36 mL to reach the end point. Report the molar concentration of the titrant.

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter7: Neutralization Titrations And Graphical Representations

Section: Chapter Questions

Problem 13P

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