A sample of powdered milk weighing 1.450 g was mixed with a buffer of pH 11.5. A few drops of Calmagite indicator were added and the solution required 31.62 mL of 1.538 x 10-2 M EDTA to reach the end point color change. Calculate the percentage of calcium in the milk. In the reaction of EDTA and calcium, one mole of EDTA reacts with one mole of calcium.

A sample of powdered milk weighing 1.450 g was mixed with a buffer of pH 11.5. A few drops of Calmagite indicator were added and the solution required 31.62 mL of 1.538 x 10-2 M EDTA to reach the end point color change. Calculate the percentage of calcium in the milk. In the reaction of EDTA and calcium, one mole of EDTA reacts with one mole of calcium.

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter19: The Chemistry Of The Main-group Elements

Section: Chapter Questions

Problem 64QRT

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