bigKIDmarie* (下午 03:22) : a passage from my chem textbk: a d.c. power supply acts as an electron pump. if forces electrons from its negative pole to the cathode of the electrolytic cell. the cathode thus has excess electrons and becomes negatively charged. does it mean that the d.c. power supply sends electrons to the cathode? but before the electrolyte starts decomposing, i.e. before it can conduct electricity, the circuit of d.c. supply + wire + graphite rod + electrolyte is not closed. So why is that the electrons can flow to the cathode?