To calculate the concentration of [Fe SCN 6]3-, we can use the Beer-Lambert Law, which relates the absorbance A of a solution to its concentration c and path length l through the equation:A = clWhere is the molar absorptivity of the complex ion at 450 nm. However, we do not have the value of in the given information. Without the molar absorptivity, we cannot directly calculate the concentration of [Fe SCN 6]3- using the Beer-Lambert Law.Alternatively, if we had the equilibrium constant Kf for the formation of the complex ion, we could use an ICE table Initial, Change, Equilibrium to determine the concentration of [Fe SCN 6]3-. Unfortunately, the equilibrium constant is not provided either.In summary, without the molar absorptivity or the equilibrium constant, we cannot calculate the concentration of [Fe SCN 6]3- in this case.