Standard CaCO, is used to standardize the EDTA solution prior to titration. Suppose 0.385 g of CaCO, was dissolved and diluted to 250.0 mL. A 25.0 mL aliquot of this standard CaCO3 solution was then titrated to endpoint using 29.50 ml. of the EDTA solution. Afterwards, the standardized EDTA solution was used to analyze the hardness of a 1000-ml water sample buffered at pH 10. The sample required 44.35 ml. of the EDTA solution to reach the endpoint. Determine the hardness of the sample in ppm CaCO3.

Standard CaCO, is used to standardize the EDTA solution prior to titration. Suppose 0.385 g of CaCO, was dissolved and diluted to 250.0 mL. A 25.0 mL aliquot of this standard CaCO3 solution was then titrated to endpoint using 29.50 ml. of the EDTA solution. Afterwards, the standardized EDTA solution was used to analyze the hardness of a 1000-ml water sample buffered at pH 10. The sample required 44.35 ml. of the EDTA solution to reach the endpoint. Determine the hardness of the sample in ppm CaCO3.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.42QAP

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