The properties of the n-Si electrode in both aqueous and organic solution for nonstabilizing conditions were studied by the electroreflectance and capacitance techniques. A shift bf the flatband potential in the anodic direction up to 0 V-SCE has been observed for both solutions and was more pronounced for the aqueous one. The strong influence of polarization under anodic potentials on the properties of the Si/electrolyte junction is shown. It is demonstrated that the flatband potential shifts for solutions without a stabilizing agent is caused by the slow oxidation process and related interface state evolution. Anomalously high electroreflectance signals have been observed for the potentials where a capacitance peak associated with the interface states is detected. We suppose the interaction of hydrogen-related species in a subsurface Si layer with interface states to be responsible for this specific electroreflectance modulation.