An EDTA solution was prepared by dissolving approximately 4 g of the disodium salt in approximately 1 L of water. An average of 12.35 mL of this solution was required to titrate 50.00-mL aliquots of a standard that contained 0.07682 g of MgCO3. Titration of a 25.00-mL sample containing MgCl2 at pH 10 required 18.81 mL of the EDTA solution. Calculate the molar concentration of MgCl2 in the sample.

An EDTA solution was prepared by dissolving approximately 4 g of the disodium salt in approximately 1 L of water. An average of 12.35 mL of this solution was required to titrate 50.00-mL aliquots of a standard that contained 0.07682 g of MgCO3. Titration of a 25.00-mL sample containing MgCl2 at pH 10 required 18.81 mL of the EDTA solution. Calculate the molar concentration of MgCl2 in the sample.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.33QAP

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An EDTA solution was prepared by dissolving approximately 4 g of the disodium salt in approximately 1Lof water. An average of 42.35 mL of this solution was required to titrate 50.00-mL aliquots of a standard that contained 0.7682 g of MgCO3 per liter. Titration of a 25.00-mL sample of mineral water at pH 10 required 18.81 mL of the EDTA solution. A 50.00-mL aliquot of the mineral water was rendered strongly alkaline to precipitate the magnesium at Mg(OH)2. Titration with a calcium-specific indicator required 31.54 mL of the EDTA solution. Calculate (a) the molar concentration of the EDTA solution, (b) the concentration of CaCO3 in the mineral water in ppm, (c) the concentration of MgCO3 in the mineral water in ppm. observe significant figures
An antacid tablet, weighing 1.25 g, was dissolved in a 1.0 L volumetric flask to allow for determination of calcium carbonate and magnesium carbonate contents. After preparing the solution, an aliquot of 10.0 ml was transferred to an Erlenmeyer flask containing a buffer solution with pH = 10. This aliquot was then titrated with EDTA 0.0040 mol/L and the average volume spent was 15.01 mL. To measure calcium after precipitation After the magnesium was fractionated, a second 10.00 mL aliquot of the stock solution was transferred to an Erlenmeyer flask. and the pH of the present solution was adjusted to a value of approximately 13. In EDTA titration, the volume consumed for observation of the end point was equal to 13.03 mL. Based on this information, (a) Outline the two steps involved, representing the related reactions. (b) Calculate the concentrations of CaCO3 and MgCO3 present in the initial solution. (c) Calculate the masses of CaCO3 and MgCO3 present in the pellet. (d) Calculate the…
. An antacid tablet, weighing 1.25 g, was dissolved in a 1.0 L volumetric flask to allow for determination of calcium carbonate and magnesium carbonate contents. After preparing the solution, an aliquot of 10.0 ml was transferred to an Erlenmeyer flask containing a buffer solution with pH = 10. This aliquot was then titrated with EDTA 0.0040 mol/L and the average volume spent was 15.01 mL. To measure calcium after precipitation. After the magnesium was fractionated, a second 10.00 mL aliquot of the stock solution was transferred to an Erlenmeyer flask, and the pH of the present solution was adjusted to a value of approximately 13. In EDTA titration, the volume consumed for observation of the end point was equal to 13.03 mL. Based on this information, a) Outline the two steps involved, representing the related reactions./5 b) Calculate the concentrations of CaCO3 and MgCO3 present in the initial solution./6 c) Calculate the masses of CaCO3 and MgCO3 present in the pellet./6 d) Calculate…
3. An antacid tablet, weighing 1.25 g, was dissolved in a 1.0 L volumetric flask to allow for determination of calcium carbonate and magnesium carbonate contents. After preparing the solution, an aliquot of 10.0 ml was transferred to an Erlenmeyer flask containing a buffer solution with pH = 10. This aliquot was then titrated with EDTA 0.0040 mol/L and the average volume spent was 15.01 mL. To measure calcium after precipitation. After the magnesium was fractionated, a second 10.00 mL aliquot of the stock solution was transferred to an Erlenmeyer flask, and the pH of the present solution was adjusted to a value of approximately 13. In EDTA titration, the volume consumed for observation ofthe end point was equal to 13.03 mL. Based on this information,a) Outline the two steps involved, representing the related reactions./5b) Calculate the concentrations of CaCO3 and MgCO3 present in the initialsolution./6c) Calculate the masses of CaCO3 and MgCO3 present in the pellet./6d) Calculate the…
A 50.00 ml aliquot of a solution containing Ca2+ and Mg2+ was buffered at pH 10 and titrated with 0.0418 M EDTA. The endpoint volume was 44.36 ml. A second aliquot of the same mixture was made strongly basic by the addition of NaOH – this causes the Mg2+ to precipitate as Mg(OH)2. The solution was then titrated with the 0.0418 M EDTA and the endpoint volume was found to be 30.02 ml. Calculate the molar concentration of Mg.
Write the involved chemical reactions for this: An EDTA solution was prepared by dissolving approximately 4 g of the disodium salt in approximately 1Lof water. An average of 42.35 mL of this solution was required to titrate 50.00-mL aliquots of a standard that contained 0.7682 g of MgCO3 per liter. Titration of a 25.00-mL sample of mineral water at pH 10 required 18.81 mL of the EDTA solution. A 50.00-mL aliquot of the mineral water was rendered strongly alkaline to precipitate the magnesium at Mg(OH)2. Titration with a calcium-specific indicator required 31.54 mL of the EDTA solution. Calculate (a) the molar concentration of the EDTA solution, (b) the concentration of CaCO3 in the mineral water in ppm, (c) the concentration of MgCO3 in the mineral water in ppm.
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An EDTA solution was prepared by dissolving approximately 4g of the disodium salt in approximately 1L of water. An average 12.35mL of of this solution was required to titrate 50.00mL aliquots of a standard that contained 0.07682g of MgCO3. Titration of a 25.00mL sample containing MgCl2 at pH 10 required 18.81mL of the solution. Calculate the molar concentration of MgCl2 in the sample.
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