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A student mixes 5.00 mL of 0.0020 M Fe(NO3)3 with 4.00 mL of 0.0020 M KSCN solution and 1.00 mL water at a certain temperature. He places a sample of the resulting solution in a spectrometer, and measures the transmittance as 31% at 447 nm.

a) What are the initial concentration of [Fe3+] and [SCN-]?

b) What are the final concentrations of [Fe3+], [SCN-], and [FeSCN2+]?

c) What is the measured value of Keq?

The molar absorptivity at 447 nm (Îµ = 4400). Path length = 1 cm.

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Related questions

a student mixes 5.00 mL of 0.0020 M Fe(NO3)3 with 5.00 mL of.0020 KSCN solution at a certain temperature. He places a smaple ofthe resulting solution in a spectrometer, and measures thetransmittance as 37% at 447 nm.

a. What are the initial concentrations of FE and SCN

b. What are the final concentrations of FE, SCN, and FeSCN?

c. What is the measured value of Keq? PLEASE EXPLAIN STEPS FOR ALL POINTS WHICH I WILL GLADLY REWARD IFUNDERSTOOD< THANK YOU

beigecamel686

1) A solution is 1.00x10^-4 M in SCN^- an0.36 M in Fe³⁺ are mixed and react according to equationâ¨â¨

Fe³⁺_(aq)+SCN^-_(aq)<--> (Fe(SCN))²⁺_(aq)

Under these conditions, the equilibrium is driven all of the way tothe right. The absorbance of the solution at 447 nm is 0.500, andthe path length of the test tube is 1.00 cm. What is the value ofthe molar absorptivity, Îµ, for the complex FeSCN²⁺?

2) In a test tube, you combine the following:

2.00 mL of 0.00200 M Fe(NO₃)₃solution
2.00 mL of 0.00100 M KSCN solution
1.00 mL of 2.0 M HNO₃ solution
3.00 mL of distilled water

a) What are the initial concentration of the reactants (i.e.,assuming no reaction occurs)?
(Fe³⁺)_init = M
(SCN^-)_init= M

b) The absorbance of the resulting solution is 0.101 at 447 nm.What is the equilibrium concentration of the FeSCN²⁺product, based on the molar absorptivity determined above?

(FeSCN²⁺)_equil= M

c) Set up an ICE table for the reaction, and determine the value ofKc from the data

Kc=