A 500.00 mg vitamin C (MW 176.12 g/mol) tablet was ground, acidified and dissolved in H2O to make a 250.0 mL solution. A 25.00 mL aliquot containing vitamin C, KI and starch was analyzed and titrated with 10.10 mL of 0.009128 M KIO3. what is the % vitamin C in the tablet.

A 500.00 mg vitamin C (MW 176.12 g/mol) tablet was ground, acidified and dissolved in H2O to make a 250.0 mL solution. A 25.00 mL aliquot containing vitamin C, KI and starch was analyzed and titrated with 10.10 mL of 0.009128 M KIO3. what is the % vitamin C in the tablet.

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter17: Electrochemistry

Section: Chapter Questions

Problem 80AP

See similar textbooks

Similar questions

A 500.00 mg vitamin C (MW176.12g/mol) tablet was ground, acidified, and dissolved in H2O to make a 250.0 mL solution. A 50.00 mL aliquot containing vitamin C, KI and starch was analyzed and titrated with 12.31 mL of 0.01042 M KIO3. What is the % (w/w) vitamin C in the tablet? KIO3 + 5 KI + 6 H+ = 3 I2 + 6 K+ + 3 H2O C6H8O6 + I2 = C6H6O6 + 2I- + 2H+ A 67.77 % B 33.89 % C 22.59 % D 3.39 %
A 500.00 mg vitamin C (MW176.12g/mol) tablet was ground, acidified, and dissolved in H2O to make a 250.0 mL solution. A 50.00 mL aliquot containing vitamin C, KI and starch was analyzed and titrated with 12.31 mL of 0.01042 M KIO3. What is the % (w/w) vitamin C in the tablet? KIO3 + 5 KI + 6 H+ = 3 I2 + 6 K+ + 3 H2O C6H8O6 + I2 = C6H6O6 + 2I- + 2H+ 67.77 % 3.39 % 22.59 % 33.89 %
A 500-mg tablet of commercial vitamin C tablet was dissolved in 50 mL water, treated with excess KI solution and 3 drops of starch solution. The solution required 4.8 mL of 0.05 M KIO3 to reach the endpoint. Calculate the % by weight of vitamin C in the tablet. (Molar mass of vitamin C = 172.16 g mol-1) IO3‐ + 5 I‐ + 6 H+ → 3 I2 + 3 H2O (1) I2 + C6H8O6 → C6H8O6* + 2 H+ + 2 I‐ (2) I2 + starch → (I2 - starch) (deep blue color) (3) *oxidized product of vitamin C
Oral rehydration salts are stated to contain the following components: Sodium Chloride 3.5g Potassium Chloride 1.5g Sodium Citrate 2.9g Anhydrous Glucose 20.0g 8.342 g of oral rehydration salts are dissolved in 500 ml of water. 5 ml of the solution is diluted to 100 ml and then 5 ml is taken from the diluted sample and is diluted to 100 ml. The sodium content of the sample is then determined by flame photometry. The sodium salts used to prepare the mixture were: Trisodium citrate hydrate (C6H5Na3O7, 2H2O) MW 294.1 and sodium chloride (NaCl) NW 58.5. Atomic weight of Na = 23. The content of Na in the diluted sample was determined to be 0.3210 mg/100 ml. Determine the % of stated content of Na in the sample. The stated should be 104.5, how??
Oral rehydration salts are stated to contain the following components: Sodium Chloride 3.5g Potassium Chloride 1.5g Sodium Citrate 2.9g Anhydrous Glucose 20.0g 8.342 g of oral rehydration salts are dissolved in 500 ml of water. 5 ml of the solution is diluted to 100 ml and then 5 ml is taken from the diluted sample and is diluted to 100 ml. The sodium content of the sample is then determined by flame photometry. The sodium salts used to prepare the mixture were: Trisodium citrate hydrate (C6H5Na3O7, 2H2O) MW 294.1 and sodium chloride (NaCl) NW 58.5. Atomic weight of Na = 23. The content of Na in the diluted sample was determined to be 0.3210 mg/100 ml. Determine the % of stated content of Na in the sample.
Calculate the final molarity of H2O2H2O2 if 1.3 mL1.3 mL of the 3.0% w/w H2O23.0% w/w H2O2 solution is diluted with 3.7 mL3.7 mL water, then added to 5.0 mL5.0 mL of a starch-iodide solution.
Precipitimetry The chloride in a 4.321-g food sample was precipitated through the addition of 50.00 mL of a standard AgNO3 solution (10.00 mL AgNO3 = 11.22 mL KSCN). The precipitate was coated with nitrobenzene and the mixture was diluted to 250.0 mL. A 50.00 mL aliquot was taken from the diluted solution and required 4.56 mL back titration with a %3D standard KSCN solution (22.33 mL KSCN = 0.9758 g AgNO3). %3D Formula Masses: AgNO3 = 169.87; CI = 35.45 Calculate the following: 1. Molar concentration of KSCN solution M %3D 2. Molar concentration of AgNO3 solution M %3D 3. % (w/w) chloride in the original sample =
The calcium (AW= 40.08 g/mol) from a sample of limestone weighing 607.4 mg was precipitated as calcium oxalate hydrate (CaC204.H20, FW 146.12 g/mol) and ignited to calcium carbonate (CaCO3, FW= 100.09 g/mol) weighing 246.7 mg. (c) If the precipitate had been ignited at a higher temperature giving calcium oxide (CaO, FW= 56.08 g/mol), what would be its weight?
Calculate the molar concentration of a thiosulfate solution from the following information:A 40.-mL aliquot of a 0.00653 M KIO3 solution is added to a flask containing 2 g of KI and 10 mL of 0.5 M H2SO4. The resulting solution is titrated to a starch endpoint with 38 mL of the thiosulfate solution.
Materials/Chemicals: Volumetric flasks Beakers Serologic pipetters Aspirators Vials/test tubes Cone. H3PO4 (85% w/w, sp gr. 1.70, MM 98) Cone. HCL (37.3% w/w sp. Gr. 1.18, MM 36) Glacial acetic acid (99.7% ww, sp gr. 1.05, MM 60) NaOH pellets NaH2PO4 Na2HPO4 Acid-base indicators: Bromophenol Blue Bromocresol green Phenol red Methyl red Methyl orange Phenolphthalein Thymol Blue pH paper pH meter Weighing balance For chemicals, refer from the template below. Research the chemicals to be used especially those that are new to you and write down the information needed. Name of Chemical Molec. Weight (g/mol) Melting point Boiling point Density (g/mL) General properties Methodolody: (Include a short summary of the overall experimental plan you are going to run. You may use flow chart or bullet form for this part. Sketches of any experimental set-ups used in the experiment or the workup procedures). Preparation of buffers Prepare 250ml of the…
Calculate the final molarity of H2O2H2O2 if 5.9 mL5.9 mL of a 3.0% w/w H2O23.0% w/w H2O2 solution, which has a density of 1.0 g/mL,1.0 g/mL, is added to 5.9 mL5.9 mL of a starch-iodide solution. final [H2O2]=[H2O2]= MM Calculate the final molarity of H2O2H2O2 if 1.6 mL1.6 mL of the 3.0% w/w H2O23.0% w/w H2O2 solution is diluted with 3.4 mL3.4 mL water, then added to 5.0 mL5.0 mL of a starch-iodide solution. final [H2O2]=[H2O2]= M
Five white, 500-mg uncoated ascorbic acid (AA) tablets with an average weight of 0.6152-g were pulverized in a mortar. A sample of the powdered ascorbic acid weighing 0.4700-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 47.81-mL of 0.09640 N 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 2.73-mL of 0.09123 N 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. 293.3 mg 502.5 mg None of the choices 383.9 mg