Chemistry

posted by .

1) Frank and Oswalt report a molar absorptivity of 4700 L mol^-1 cm^-1 for thiocyanatoiron(lll) ion. What absorbance would you expect for a soloution that it 1.0e-4 M in thiocyanatorion(lll) ion, if the path length is 1.00 cm?

2) At a given temperature, the equilibrium constant for the system studied in this experiment is 1.40e+2. Suppose 100.0 ml of 2.00e-3 M KSCN was mixed with 100.0 ml of 2.00e-3 M Fe(NO_3_)_3_. At equilibrium, what molar concentration of the thiocyanatoiron(lll) ion would you expect?

  • Chemistry -

    A = abc
    A = 4700*1*1E-4
    Solve for absorbance.

    100 mL x 2E-3 = 0.2 millioles Fe^3+
    100 mL x 2E-3 = 0.2 millimols SCN^-
    (Fe^3+) = 0.2 mmols/200 mL = 0.001M
    (SCN^-) = likewise = 0.001M
    .......SCN^- + Fe^3+ ==> FeSCN^2+
    .....0.001....0.001.......0
    C......-x.......-x.........x
    E....0.001-x..0.001-x......x

    Keq = 140 = (FeSCN^2+)/(SCN^-)(Fe^3+)
    Substitute from the E line and solve for x

  • Chemistry -

    2.00x10^-3

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. DrBob222-Questions

    Can you please check these for me. Thank you very much in return:-) For Al2(SO4)3 you gave me Aluminum ion and Sulfate ion. These are the rest: CaCl2 = Calcium ion and Chlorite ion Na2O = Sodium ion and Oxygen ion AgCl = silver ion …
  2. Chemistry 102

    The Ksp for cerium iodate, Ce(IO3)3 is 3.2 e-10. What is the molar solubility of Ce ion in pure water?
  3. chemistry

    At l=530 nm:aCuSO4=7.544L/mol-cm aKMnO4= 3.645 L/mol-cm At l=800nm: aCuSO4=2.908L/mol-cm aKMnO4= 5.412L/mol-cm you use a celleith a path length of 1.0cm An unknown solution containing both CuSO4 and KMnO4 gave an absorbance reading …
  4. Chemistry

    The absorbance of a chlorophyll a standard solution in ethanol (density = 0.785 g/mL) is measured in a 1.3 cm cuvette or path length. The absorbance is 0.435 and the molar absorptivity coefficient is 86,300 M–1cm–1. The molecular …
  5. Chemistry

    The absorbance of a chlorophyll a standard solution in ethanol (density = 0.785 g/mL) is measured in a 1.3 cm cuvette or path length. The absorbance is 0.435 and the molar absorptivity coefficient is 86,300 M–1cm–1. The molecular …
  6. Chemistry

    Transferrin (T) - Molar mass = 81000g/mol - carries 2 Fe3+ ions Deferrioxxamine B (DB) molar mass = 650g/mol - carries 1 Fe3+ at wavelength 428 molar absorptivity T = 3240 molar absorptivity DB = 2630 at wavelength 470 molar absorptivity …
  7. General Chemistry.

    The absorbance of a chlorophyll a standard solution in ethanol (density = 0.785 g/mL) is measured in a 1.3 cm cuvette or path length. The absorbance is 0.765 and the molar absorptivity coefficient is 86,300 M–1cm–1. The molecular …
  8. College Chemistry lab

    How do I Calculate the concentration of iron(lll) with absorbance measurement. Wavelength is 480nm, solution is 1 ml FeCl3 : 9ml HCl, absorption is .250A, concentration of stock FeCl3 solution is 0.00050M and stock HCl solution is …
  9. Tulane University

    Frank and Oswalt report a molar absorptivity of 4700 L mol^-1 cm^-1 for thiocyanatoiron(lll) ion. What absorbance would you expect for a soloution that it 1.0e-4 M in thiocyanatorion(lll) ion, if the path length is 1.00 cm?
  10. Chemistry

    A solution is prepared by adding 45.0g of Na2SO4*6H2O to pure water to make 150mL of solution. What are molar concentrations of these ions in the resulting solution?

More Similar Questions