Operating Wavelength: 445 nm
Preparation of Standard Calibration Curve of [FeSCN]2+

Sample Number Absorbance Final Concentration of [FeSCN]2+ (M)
A 0.145 4.0E-5
B 0.255 8.0E-5
C 0.410 1.2E-4
D 0.640 1.6E-4
E 0.810 2.0E-4

Determination of [FeSCN]2+ in Equilibrium Mixtures

Sample Number Absorbance
1 0.290
2 0.310
3 0.410
4 0.510

For Sample #1:
Enter the initial concentration of Fe3+. (M)
Calculate the equilibrium concentration of Fe3+. (M)
Enter the initial concentration of HSCN. (M)
Calculate the equilibrium concentration of HSCN. (M)
Calculate Keq for sample 1.
For Sample #2:
Enter the initial concentration of Fe3+. (M)
Calculate the equilibrium concentration of Fe3+. (M)
Enter the initial concentration of HSCN. (M)
Calculate the equilibrium concentration of HSCN. (M)
Calculate Keq for sample 2.
For Sample #3:
Enter the initial concentration of Fe3+. (M)
Calculate the equilibrium concentration of Fe3+. (M)
Enter the initial concentration of HSCN. (M)
Calculate the equilibrium concentration of HSCN. (M)
Calculate Keq for sample 3.
For Sample #4:
Enter the initial concentration of Fe3+. (M)
Calculate the equilibrium concentration of Fe3+. (M)
Enter the initial concentration of HSCN. (M)
Calculate the equilibrium concentration of HSCN. (M)
Calculate Keq for sample 4.
Calculate average Keq using the Keq using the 4 samples.