Titration of Ca²+ and Mg²+ in a 50.00-mL hard water sample required 23.65 mL of 0.01205 M EDTA. Asecond 50.00-mL aliquot was made strongly basic with NaOH to precipitate Mg²+ as Mg(OH)2(s). Thesupernatant liquid was titrated with 14.53 mL of the EDTA solution. Calculate the total hardness of thewater sample, expressed as ppm CaCO3.

A question based on environmental pollution that is to be accomplished.

. Titration of Ca²+ and Mg²+ in a 50.00-mL hard water sample required 23.65 mL of 0.01205 M EDTA. A second 50.00-mL aliquot was made strongly basic with NaOH to precipitate Mg2+ as Mg(OH)2(s). The supernatant liquid was titrated with 14.53 mL of the EDTA solution. Calculate the total hardness of the water sample, expressed as ppm CaCO3.

. Titration of Ca²+ and Mg²+ in a 50.00-mL hard water sample required 23.65 mL of 0.01205 M EDTA. A second 50.00-mL aliquot was made strongly basic with NaOH to precipitate Mg2+ as Mg(OH)2(s). The supernatant liquid was titrated with 14.53 mL of the EDTA solution. Calculate the total hardness of the water sample, expressed as ppm CaCO3.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter16: Applications Of Neutralization Titrations

Section: Chapter Questions

Problem 16.20QAP

See similar textbooks

Similar questions

Five white, 500-mg uncoated ascorbic acid (AA) tablets with an average weight of 0.6100-g were pulverized in a mortar. A sample of the powdered ascorbic acid weighing 0.4610-g was placed in an iodine flask and was dissolved in 50-mL H2SO4 then 5-g of KBr was added to the resulting solution. The solution was titrated with 46.73-mL of 0.0152 M STD. KBrO3 to reach a faint yellow endpoint then 3-g KI and 5-mL Starch TS. The blue color solution is then titrated with 2.78-mL of 0.1047 M STD. Na2S2O3 to reach the disappearance of the blue iodostarch complex. MW: KBrO3 = 167.0 ; KIO3 = 214.0 ; Na2S2O3 = 158.11 ; C6H8O6 = 176.12 Compute the milligrams of pure AA per tablet from the assay. None of the choices 349.7 mg 264.3 mg 462.7 mg
An EDTA solution prepared from its disodium salt was standardized using 0.250-g primary standard CaCO3 (MW=100.087) and consumed 28.50 mL of the solution. The standard solution was used to determine the hardness of a 2.0 L sample of mineral water, which required 35.57 mL EDTA solution. Express the analysis in terms of ppm CaCO3
1) 100 mL tap water is titrated with 20 mL of 0.02 M EDTA solution to determine the hardness of the water. The second 100 mL tap water is precipitated as CaC2O4 and removed by filtration and the filtrate is titrated with 8.0 mL of the same EDTA solution. What are the concentrations (as ppm) of Ca2+ (40.078 g/mol) and Mg2+ (24.305 g/mol) ions in the water? 2) 10 g of a solution, containing one or more of NaOH, Na3PO4, Na2HPO4, NaH2PO4, H3PO4 and HCl substances, is titrated with 1.0 M NaOH using the phenolphthalein indicator and 34.5 mL NaOH is used. Another 10 g mixture was titrated to reach the bromocresol green end point and 20.50 mL NaOH is used. What is the composition of the solution? What are the percentages of the species(H:1.0078, O:15.99, Na: 22.98, P:30.974, Cl:35.453)?
Titration of 25.0 mL of a 0.0500 M Zn2+ solution with 0.0550 M EDTA in a solution buffered at pH 8. Assume that the temperature is 25 oC and that the formation constant for Zn2+ is 3.13 x 1016 at this temperature. What is the pZn of the solution after 30 mL of titrant have been added?
A sample of water from a river was analyzed by titrating a 125 mL aliquot with 0.0210 M EDTA, consuming 22.52 mL. Express the hardness of the water in ppm of CaCO3.
Given that the titration of Ca2+ and Mg2+ in a 50.00-mL sample of hard water required 22.35 mL of 0.01115 M EDTA. A second 50.00-mL aliquot was made strongly basic with NaOH to precipitate the Mg2+ as Mg(OH)2(s) . The supernatant liquid was titrated with 15.19 mL of the EDTA solution. Calculate the concentration in ppm of CaCO3 in the sample.
Twenty sodium salicylate tablets labeled 325 mg were dispersed in sufficient water to make 200.0 mL. A 15.0–mL aliquot of the filtrate was titrated to a bromophenol blue endpoint in the usual way by 32.11 mL of 0.1000 N hydrochloric acid. Calculate the amount of sodium salicylate in each tablet, and from that, the percentage of the labeled amount. (NaC7H5O3 MW = 160.11 g/mol) Amount of sodium salicylate in each tablet = % labelled amount =
An impure sample of calcium carbonate with a mass of 7.95 g was reacted with 50.00 cm3 of 1.00 mol dm hydrochloric acid (an excess). The resulling solution was transferred to a volumetric flask and titrated with 11.10cm3 of 0.300 mol dm-3 sodium hydroxide solution. Determine the percentage purity by mass of the calcium carbonate sample.CaCO3 + HCl -> CaCl2 + H2O + CO2 HCl + NaOH -> NaCl +H2O a. Determine how many moles of hydrochloric acid were used.b. Determine how many moles of excess HCI was titratedc. Determine how much in moles calcium carbonate present in the sample.d. Calculate the mass of calcium carbonate presente. Determine the percentwge calcium carbonate is in the sample.
Calculate the hardness in terms of parts per million calcium carbonate (100.0869 g/mol) in a 50.00 mL aliquot of milk sample. The sample was treated with a small amount of ammonia buffer to bring the pH to 10 followed by the addition of 10 drops EBT indicator. The milk sample required 10.00 mL of 8.000 x 10-3 M EDTA for titration. 160 ppm 4 80 320
In the determination of water hardness by volumetry, AEDT is used. If the volume of 0.01 M EDTA used to titrate 100 mL of sample was 20 mL, calculate the total hardness expressed in mg/L of CaCO3.
The solubility of borax, which is made up of sodium tetraborate (Na2B4O5(OH)4 8H2O), was analyzed. The dissolution of borax is: Na2B4O5(OH)4 • 8H2O(s) ⇌ 2 Na+(aq) + B4O5(OH)42–(aq) + 8 H2O(l) A 50 mL saturated solution was prepared. After filtration of solution, 5 mL aliquot was transferred to a flask and titrated using 0.432 M HCl. The endpoint was found to be 4.73 mL of the titrant. Tetraborate anion (B4O5(OH)42-) is a weak base which reacts with HCl like the following reaction: B4O5(OH)42–(aq) + 2 H+(aq) + 3 H2O(l) ⇌ 4 H3BO3(aq) What is Ksp expression for the dissolution? What is the tetraborate ions concentration in the filtrate? What is the molar solubility and Ksp of borax if the titration was done at room temperature (298 K)?
A mixture containing only KCl and NaBr is analyzed by the Mohr Method. A 0.3172-g sample is dissolved in 50 mL water and titrated to the Ag2CrO4 endpoint, requiring 36.85 mL of 0.1120 M AgNO3. A blank titration requires 0.71 mL of titrant to reach the same endpoint. Report the % (w/w) KCl and NaBr in the sample. [Answer should be 82.41 % (w /w)]