I need help in calculating the total mass of the unknown #2 sample of copper. The following chemical equations are in used: 2 Cu2+ + 4 I -> 2 Cus + I2 I2 + 2 S2O3-2 -> 2 I +S4O6-2 To standardize the Sodium Thiosulfate Average copper weight = 0.2536 g Average volume = 25.46 mL The Analysis of the Unknown #2 sample of copper Average mass of the unknown #2 sample of copper = 1.2474 g Average volume of sodium thiosulfate = 14.30 mL I came up with a molarity of 0.1567 for NaS2O3. Is it correct? I am coming up for the mass of the unknown #2 sample of copper: 0.1348 grams. Is that also correct?

I need help in calculating the total mass of the unknown #2 sample of copper. The following chemical equations are in used: 2 Cu2+ + 4 I -> 2 Cus + I2 I2 + 2 S2O3-2 -> 2 I +S4O6-2 To standardize the Sodium Thiosulfate Average copper weight = 0.2536 g Average volume = 25.46 mL The Analysis of the Unknown #2 sample of copper Average mass of the unknown #2 sample of copper = 1.2474 g Average volume of sodium thiosulfate = 14.30 mL I came up with a molarity of 0.1567 for NaS2O3. Is it correct? I am coming up for the mass of the unknown #2 sample of copper: 0.1348 grams. Is that also correct?

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter20: Applications Of Oxidation/reduction Titrations

Section: Chapter Questions

Problem 20.25QAP

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