Potentiometry was employed to investigate the formation of complexes between EDTA and Cu2+ ions in aqueous solution. To do so, the potential of a Cu electrode was measured in a series of solutions containing 1 mM Cu(NO3)2, 100 mM KNO3, and varying concentrations of EDTA (added as the tetrasodium salt). Using the data provided below, calculate the formation constant (K) of the Cu2+-EDTA complex. CEDTA / ME / V vs. SHE 1 x 10-6 0.252 1 x 10-5 0.252 1 10-4 0.251 5 10-4 0.243 0.001 0.098 0.002 -0.056 0.005 -0.074 0.010 -0.085 0.100 -0.116 1.000 -0.145