A rock was analyzed for its copper content. Since copper goes through redox reactions, an iodometric totration was utilized. An unknown 1.5098 g sample was acidified using 3M sulfuric acid to dissolve the Cu compounds and diluted w/ 30mL distilled water. Kl was then added resulting in l2 and Cul precipitate from Cu2+ (first reaction). I2 then reacted with excess Ki resulting in 13 (second reaction) w/c was titrated with Na2S203 (third reaction). 17.600mL of the titrant was required in the solution to reach the starch end point. Before the the sample was titrated, the titrant was standardized by taking 50mL of 6.786e-3 standard KIO3 sol'n, acidifying and adding KI crystals. 9.8mL was required for the titration of this solution to reach starch endpoint. a. Give the concentration (M) of S₂O3² titrant. wwwwwww b. Give the copper content of the rock (%w/w)

A rock was analyzed for its copper content. Since copper goes through redox reactions, an iodometric totration was utilized. An unknown 1.5098 g sample was acidified using 3M sulfuric acid to dissolve the Cu compounds and diluted w/ 30mL distilled water. Kl was then added resulting in l2 and Cul precipitate from Cu2+ (first reaction). I2 then reacted with excess Ki resulting in 13 (second reaction) w/c was titrated with Na2S203 (third reaction). 17.600mL of the titrant was required in the solution to reach the starch end point. Before the the sample was titrated, the titrant was standardized by taking 50mL of 6.786e-3 standard KIO3 sol'n, acidifying and adding KI crystals. 9.8mL was required for the titration of this solution to reach starch endpoint. a. Give the concentration (M) of S₂O3² titrant. wwwwwww b. Give the copper content of the rock (%w/w)

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 1.1324 g sample of magnetite ore was dissolved in concentrated HCl to give a solution that contained a mixture of Fe2+ and Fe3+. Nitric acid was added and the solution was boiled for a few minutes, which converted all of the iron to Fe3+. The Fe3+ was then precipitated as Fe2O3*xH2O by addition of NH3. After filtration and washing, the residue was ignited at a high temp to give 0.5394 g of pure Fe2O3. What is the percent Fe and the percent Fe3O4 in the sample?
A scientist was tasked to extract Fe from an aqueous suspension that contains 106 g of Fe2O3. The following steps detail the transformation of Fe2O3 (aq) to elemental iron: I. Enough sulfur trioxide gas was bubbled to Fe2O3 aqueous suspension to completely yield ferric sulfate. II. Then, 5.00 M nitric acid was added to ferric sulfate yielding an aqueous solution of ferric nitrate. III. Excess magnesium powder was added to the aqueous solution of ferric nitrate precipitating the solid iron ----- a. Write the balanced chemical reaction and the type of chemical reaction for [I], [II], [III]. Do not forget to indicate the states of the reactants and products (s, l, g).(CHOICES: COMBINATION, SINGLE DISPLACEMENT, DOUBLE DISPLACEMENT) b. What is the final mass of iron? Express final answers in 3 significant figures. c. High-concentration HCl is supposed to be added at the last part of the procedure. Briefly state its purpose.
A 0.4852g sample of an iron ore was dissolved in acid to the 3+ state, then precipitated as Fe2O3 x H2O. The pp was filtered, washed and calcined to Fe2O3, which gave a weight of 0.2481g. Calculate the Fe % in the sample.
An ore containing Fe3O4 was analyzed by dissolving a 1.5419-g sample in concentrated HCl. HNO3 was then added to oxidize any Fe2+ to Fe3+. The Fe3+ was precipitated as Fe(OH)3 by adding NH3. The precipitate was collected by filtration and was finally heated yielding 0.8525 g of Fe2O3. Report the concentration of Fe3O4 in the sample as %(w/w). (Note: the final answer is said to be 53.4%)
A 0.2500-g of dry CaCO3 was completely dissolved into a solution of 5-mL conc. HCl and 50-mL distilled water in an erlemeyer flask. The resulting solution was boiled for 5 minutes to expel CO2 from the reaction, and then it was cooled to room temperature and the solution was transferred in a 500-mL volumetric flask filled to volume by rinsing the erlenmeyer flask and combining all the washings to fill the mark. A 5.0-mL aliquot of the CaCl2 solution was taken from the orignal solution and was transferred into an erlenmeyer flask with 10-mL NH3 buffer, 20-mL distilled water, and 5 gtts of EBT. The solution consumed 4.96 mL of an EDTA solution. MW: CaCO3 = 100.1 Compute for the N EDTA solution. 0.0053 N 0.0531 N 0.5313 N None of the choices
One litre of a saturated aqueous solution of Ag2SO4 (MW = 311.79 g mol- 1) at 25 °C is evaporated to dryness. 4.844 g of Ag2SO4 residue was produced. What is the solubility product (Ksp)?
To determine the amount of magnetite. Fe3O4, in an impure ore, a 1.5419 g sample is dissolved in concentrated HCl, resulting in a mixture of Fe2+ and Fe3+. After adding HNO3 to oxidize Fe2+ to Fe3+ and diluting with water, Fe3+ is precipitated as Fe(OH)3 using NH3. Filtering, rinsing and igniting the ppt provides 0.8525 g of pure Fe2O3. Calculate % Fe in the sample.
Method of separation/chemical reaction (with the brief process) of 3 KG's OF SODIUM BORATE AND 1.5 KG's HYDROCHLORIC ACID
Gravimetric analysis of Fe3O4 (MW = 232 g/mole) may be undertaken with the following reactions: Fe3O4 → Fe2O3 → Fe (OH)3. Weight of sample containing 8.00% Fe3O4 that must be taken to obtain a precipitate of Fe(OH)3 (MW = 107 g/mole) that weighs 150 mg is . a. 0.108 g b. 0.325 g c. 1.355 g d. 4.065 g Amount of Fe2O3 (MW = 160 g/mole) from which 150 mg of Fe(OH)3 (MW = 107 g/mole) may be obtained is . a. 0.112 g b. 0.224 g c. 0.448 g d. none of the other choices
1. A newly discovered iron ore was weighted (5.408 g) and worked up to produced 0.3785 g of ignited Fe2O3 precipitate. What is the percent purity of the iron in the sample? 2. Distinguish between equivalence point and end point.
Six iron tablets containing FeSO4.7H2O were dissolved in 100-ml of 0.1M HNO3 with gentle heating. All of the Fe2+ is converted to Fe3+ by the strong oxidizing conditions. After the solution had cooled to room temperature , 2.5-ml of 35wt% NH4OH was added. The precipitate Fe2O3-xH2O that was filtered weighed 0.345g. Thermogravimetric analysis of the crude product showed a 10.5% weight loss . A. How many waters of hydration were in the precipitate B. How much iron is present in each tablet
An impure sample of Na3PO3 weighing 0.1392 g was dissolved in 25 mL of water. A solution containing 50 mL of 3% w/v mercury(II) chloride, 20 mL of 10% w/v sodium acetate, and 5 mL of glacial acetic acid was then prepared. The solution containing the phosphite was added dropwise to the second solution, oxidizing PO3^3– to PO4^3– and precipitating Hg2Cl2. After digesting, filtering, and rinsing, the precipitated Hg2Cl2 was found to weigh 0.4320 g. Report the purity of the original sample as %w/w Na3PO3. Moles Na3PO3 = moles Hg2Cl2