Chemistry

posted by .

These are what i used.
0.0375M sodium thiosulphate , 2.5% KI .47.2 ml copper sulphate solution.
the average volume of Na2S2O3 is 19.25 cm, i have already calculated the number of moles of thiosulphate which is 7.218 * 10-4 moles of Na2S2O3 and also the number of moles of I2 that reacted with S2O32 which was calculated to be 7.218*10^-4/2 = 3.609 * 10^-4

I have to do the calculations for :

The number of Cu2+ that reacted with I- to produce the number of moles of I2 above
The number of moles of Cu2+ in the volumetric flask
The concentration of Cu2+ in the stock solution

Any kind of help would be really appreciated!

  • Chemistry -

    You started in the middle of the question. I'm just guessing that you have performed an experiment in which you determined %Cu in a sample. The equations are Cu^2+ + KI(xs) ==> CuI(s) + I2 and I suppose you titrated the liberated I2 with thiosulfate like this
    2S2O3^2- + I2 ==> 2I^- + S4O6^2-
    mols S2O3^2-, what you titrated with is M x L = ?. Then convert this to moles Cu.
    ? mols S2O3^2- x (1 mol I2/2 mol S2O3^2-) x (2 mol Cu/1 mol I2) =? mol Cu.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Science

    What is the scentific formula for Sodium Thiosulphate?
  2. Chemistry Help Please

    Titration of a Sample of Household bleaches: The oxidizing agent in a household bleach is determined by placing 100 mL of distilled water in a 250 mL Erlenmeyer flask and adding 10 mL of the 10% (w/w) KI solution, swirling the contents …
  3. chemistry

    A drop of starch is added to a mixture of 97.30 ml of 0.1096 M I2 and 97.20 ml of 0.1098 M Na2S2O3. I've already calculated the moles of I2 to be 10.66408 moles and the moles of Na2S2O3 to be 10.67256. Will the solution be blue even …
  4. Chemistry - please help

    Please help to determine the (%w/w) benzoyl peroxide (C14H20O4) in a sample. Procedure: 2.500g of sample was dissolved in 75ml dimethylformamide and diluted to 100.0ml with the same solvent. (Solution T). To 5.0ml of Solution T, 20ml …
  5. Chemistry-iodometric titration

    In an iodometric titration, excess potassium iodide solution (KI) is added to the sample.Analyte such as chlorine liberates iodine from KI under acidic condition. Liberated iodine is titrated against standard sodium thiosulphate. The …
  6. chemistry

    A student prepares a 2M solution of copper sulphate. She adds 17 mL of the solution to a 100 mL volumetric flask and dilutes it up to a final volume of 100 mL with water. What is the final molar concentration of the copper sulphate?
  7. Chemistry

    Are the following chemicals light sensitive?
  8. swagodimo

    Calculate the number of moles of hcl(aq)added to sodium thiosulphate
  9. chemistry

    why we add acid to the standardization of sodium thiosulphate solution?
  10. Chemistry

    Mean titre of 0.2M sodium thiosulphate = 32.2 ml 1) Calculate number of moles of S2O32- which react in the titration 2)Calculate how many moles of I2 react with this amount of S2O3 3)How many Cu2+ ions are needed to liberate this amount …

More Similar Questions