The values of R1 in 0.05 M NaCl without the inhibitor were rapidly decreasing in the first 1000 s of the experiment (inset to Fig. ). Afterwards, the decrease was not so prominent, suggesting passivation of the surface with a layer of corrosion products. After ca. 3000 s the values of R1 in 0.05 M NaCl become stable in time. In the experiments with the gradual addition of sodium molybdate into 0.05 M NaCl solution, the value of R1 corresponds to the resistance of the Mo-rich surface film formed on the surface and it started to increase rapidly when the first portions of the inhibitor were added into the solution. It confirms the rapid adsorption of the inhibitor on the surface of the AZ31-xLi alloys and the passivation of their surface. In the case of the CPE constant Y0 (Fig. ), its values were almost one order of magnitude lower in the inhibited solutions, also supporting the high inhibition efficiency of aqueous molybdate. The n parameter of the CPE element (Fig. ) was generally decreasing with time and its values were in the range of 0. Open markers correspond to 0.05 M NaCl (spectra in Fig. ) and filled markers describe 0.05 M NaCl with molybdate inhibitor (spectra in Fig. ). Top x-axes correspond to concentration profile of Na2MoO4 in solutions and are valid for filled markers only.