A salt sample was analyzed for its purity. A 0.5000g sample was dissolved in water and diluted to 250.0mL. From this solution, 25.00mL was taken for analysis. To this aliquot, 20.00mL of a 0.08735M AgNOg solution was added to precipitate the chloride. The excess AgNO, required 12.45mL of a 0.09473M KSCN solution for back-titration. Calculate the purity of the salt sample as percent by mass of KCI (74.55 g/mol). (Answer: 84.63% KCI)

A salt sample was analyzed for its purity. A 0.5000g sample was dissolved in water and diluted to 250.0mL. From this solution, 25.00mL was taken for analysis. To this aliquot, 20.00mL of a 0.08735M AgNOg solution was added to precipitate the chloride. The excess AgNO, required 12.45mL of a 0.09473M KSCN solution for back-titration. Calculate the purity of the salt sample as percent by mass of KCI (74.55 g/mol). (Answer: 84.63% KCI)

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.35QAP

See similar textbooks

Similar questions

To determine the concentration of glucose in the packaged juice industry, 50 mL of sample is analyzed. Analysis of it (and other reducing sugars) was carried out there using triiodide back titration. An excess volume of 75.00 mL of 0.338 M triiodide standard solution in alkaline medium was added to the glucose solution. The resulting solution was acidified and the excess triiodide was titrated with 18.37 mL of standard 0.526 M thiosulfate solution. Calculate is the concentration in ppm in the sample. In alkaline medium: Glucose (C6H12O6) / Gluconate (C6H11O7-), Triiodide (I3- ) / Iodide (I-) In acid medium: Thiosulfate (S2O32-) / Tetrathionate (S4O62-), Triiodide (I3- ) / Iodide (I-)
A solution containing chloride ion was analyzed by the Volhard method. A 50.00 mL sample containing chloride ion was treated with 25.00 mL of 0.2500 M silver nitrate. The precipitated AgCl was removed from the solution by filtration, and 1.00 mL of 0.1000 M Fe3+ was added to the filtrate. This new solution was then titrated with 10.67 mL of 0.2380 M KSCN. What is the concentration of chloride ion in the original solution?
A salt sample was analyzed for its purity. A 0.5000 g sample was dissolved in water and diluted to 250 mL. From this solution, 25.00 mL was taken for analysis. To this aliquot, 20.00 mL of a 0.08735 M AgNO3 solution was added to precipitate the chloride. The excess AgNO3 required 12.45 mL of a 0.09473 M KSCN solution for back-titration. Calculate the purity of the salt sample as percent by mass of KCl (74.55 g/mol)
A sample containing calcium was analyzed by gravimetry, converting all calcium to calcium oxalate monohydrate (CaC2O4 • H2O). The sample weighing 0.2654 g was dissolved by adding 6M HCl, and then ammonium oxalate solution was added to precipitate all the calcium. The precipitate was suction filtered and dried in an oven at 95 °C for one hour. The solid obtained weighed 0.3216 grams.Calculate:A) The percentage of CaCO3B) The percentage of Ca C) The percentage of CaO
A salt sample was analyzed for its purity. A 0.5000g sample was dissolved in water and diluted to 250.0mL. From this solution, 25.00mL was taken for analysis. To this aliquot, 20.00mL of a 0.08735M AgNO; solution was added to precipitate the chloride. The excess AgNO required 12.45mL of a 0.09473M KSCN solution for back-titration. Calculate the purity of the salt sample as percent by mass of KCI (74.55 g/mol). (Answer: 84.63% KCI)
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)?
To determine the fluoride content in an aqueous and chloride-containing preparation of ammonium fluoride, the following analysis was performed. 105.2 mg of the preparation was dissolved in 100.0 mL of water. Then a 300 mL 40 mM lead chloride solution was added, whereby all fluoride ions were precipitated out of the solution in the form of the sparingly soluble salt PbClF (s). The precipitate was separated and washed at 15 degrees with a lead fluoride chloride saturated solution and dried at 130 degrees. The precipitate weighed 651.3 mg. a) Calculate the fluoride content (as % by weight F) in the preparation.b) Determine the purity of the ammonium fluoride preparation
A piece of Gold weighing 12,359 Kg is suspected of being contaminated with Iron. To perform an instrumental analysis and To confirm whether or not it contains Fe, a portion of the sample (0.954 g) is taken from the piece and dissolved with 25 mL of aqua regia. Heats up For its complete dissolution, it is cooled and made up to 100 mL. A 10 mL aliquot is taken from this solution and made up to 50 mL. From This last solution is given the appropriate treatment to visualize Fe+2, for which the 1,10-phenanthroline reagent is added. (it forms a complex that is red in color) and is taken to a visible spectrophotometer and with a 12 mm cell a absorbance of 0.45. Previously, a calibration curve of Fe+2 was obtained under the same instrumental conditions obtaining the following data: (view table) Calculate the purity of the gold piece, assuming impurities only due to Fe.
The arsenic in a 1.203-g sample of a pesticide was converted to H3AsO4 by suitable treatment. The acid was then neutralized, and 40.00 mL of 0.05871 M AgNO3 was added to precipitate the arsenic quantitatively as Ag3AsO4. The excess Ag+ in the filtrate and in the washings from the precipitate was titrated with 9.63 mL of 0.1000 M KSCN, and the reaction was. Find the percentage of As2O3 in the sample.
a 10g soil sample was gently stirred with 250 ml of 1.0 M CH3COO(NH4) solution for 24 h and centrifuged to separate the solution. The solution recovered after centrifugation was titrated with distilled water to a volume of 1 liter and analyzed for cations. Analytical results showed that the solution contained 20 mg/L Ca, 2 mg/L Mg, 1 mg/L K, and 0.5 mg/L Na. Calculate the number of cation exchange equivalents and express it in meq/100 g of soil
The amount of sulfate in a solid sample was determined by first dissolving 562.2 mg of sample in water, and then precipitating the sulfate by the addition of 25.00 mL of 0.022 96 M BaCl2. The precipitate was filtered from the solution and the remaining Ba2+ was titrated with 16.52 mL of 0.014 57 M EDTA. What was the mass percent of sulfate in the solid?
A mineral in a fine state of division (0.6324 g) was dissolved in 25.0 mL of 4.0 mol / L boiling HCl and diluted with 175.0 mL of H2O containing two drops of methyl red indicator. The solution was heated to 100 ° C and a heated solution containing 2.00 g of (NH4) 2C2O4 was added slowly to precipitate CaC2O4. Next, NH3 6.0 mol / L was added until the indicator changed from red to yellow, indicating that the liquid was neutral or slightly basic. After slow cooling for 1 hour, the liquid was decanted, the solid transferred to a crucible and washed five times with 0.10 wt% (NH4) 2C2O4 solution, until no Cl- was detected in the filtrate with the addition of AgNO3 solution. The crucible was dried at 105 ° C for 1 hour and then taken to an oven at 500 ° C ± 25 ° C for two hours. The mass of the empty crucible was 18.2311 g. The crucible mass with CaCO3 (s) was weighed 5 times to an average of 18.5467 g. Determine the percentage, by mass, of Ca in the mineral. Ca (40.078 g / mol); C (12.01078…