Problem: Fe3+(aq) + SCN-(aq) ⇌ FeSCN2+(aq)From known initial concentrations of Fe3+(aq) and SCN-(aq), and a spectrophotometric determination of the concentration of FeSCN2+(aq) at equilibrium, calculate Keq for this reaction from the following data.Initial Conditions: Mix 4.24 ml of 2.10 x 10 -3 M Fe(NO3)3(aq) solution with 4.66 ml of 2.50 x 10 -3 M KSCN(aq) solution in a graduated cylinder. Add water so the total volume of the solution is 10.00 ml.  Equilibrium Conditions: The equilibrium concentration of FeSCN 2+(aq) is found to be 2.27 x 10 -4 M from spectrophotometry. 

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FREE Expert Solution

We are being asked to determine the Keq for the reaction from the given data.


We are going to do the following steps:

Step 1: Determine the initial concentration of the reactants

Step 2: Draw an ICF chart

Step 3: Determine the equilibrium concentrations

Step 4: Solve for Keq

96% (487 ratings)
Problem Details

Fe3+(aq) + SCN-(aq) ⇌ FeSCN2+(aq)

From known initial concentrations of Fe3+(aq) and SCN-(aq), and a spectrophotometric determination of the concentration of FeSCN2+(aq) at equilibrium, calculate Keq for this reaction from the following data.

Initial Conditions: Mix 4.24 ml of 2.10 x 10 -3 M Fe(NO3)3(aq) solution with 4.66 ml of 2.50 x 10 -3 M KSCN(aq) solution in a graduated cylinder. Add water so the total volume of the solution is 10.00 ml.

Equilibrium Conditions: The equilibrium concentration of FeSCN 2+(aq) is found to be 2.27 x 10 -4 M from spectrophotometry. 

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