Suppose Beaker A contains Zn rod submerged in zinc sulphate solution.At the electrode/electrolyte interface ,since the force felt by the solvent molecules and ions are anisotropic because of the electrode phase, the electrical neutrality breaks down on the solution side,orientation of solvent dipole take place and a net charge develops in any volume element in the solution phase near to the electrode.This creates a net electric field across the phase boundary which result in the motion of electrons on the electrode according to the field. Suppose the net charge in the solution phase is positive and induces a equal amount of negative charge on the electrode.This induction of negative charge on electrode results in some of the Zn2+ ions who have shed the electrons to leave the electrode and enter the solution resulting in a excess charge in the bulk of the solution.To maintain electrostatic condition this excess charge reside on the surface of electrolyte.The same process happens in Beaker B containing Cu and Copper sulphate solution,but the induced charge on Cu electrode is less negative compared to Zn and the excess charge residing on the electrolyte surface is also less compared to Zn.Since Zn electrode is more negative ,the direction of field lines is from Cu to Zn.On the electrolyte Since Zn electrolyte is more positive the direction of field is from Zn to Cu.Since the both field is equal and opposite they nullify each other .Thus net field is zero.If this is the case then how come electrons moves when we hook up a wire across this electrode.Can I solve this problem just by connecting a salt bridge.Or is there any flaw in the explanation field diagram



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