Titration of a 25.00 mL sample of mineral water (containing both Ca2+ and Mg2+) at pH 10 required 19.18 mL of 0.01125M EDTA solution. Another 25.00 mL aliquot of the same mineral water was rendered strongly alkaline to precipitate the magnesium. Titration with a calcium-specific indicator required 14.92 mL of the EDTA solution. Calculate the mass of MgCO3 (FW= 84.314 g/mol) in the mineral water in mg (keep 2 decimals).

Titration of a 25.00 mL sample of mineral water (containing both Ca2+ and Mg2+) at pH 10 required 19.18 mL of 0.01125M EDTA solution. Another 25.00 mL aliquot of the same mineral water was rendered strongly alkaline to precipitate the magnesium. Titration with a calcium-specific indicator required 14.92 mL of the EDTA solution. Calculate the mass of MgCO3 (FW= 84.314 g/mol) in the mineral water in mg (keep 2 decimals).

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.29QAP

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