The difference between the current that is actually obtained, at any particular value of the potential of the @I03006@ or @W06686@, for the reduction or @O04362@ of an ionic @E01940@ and the current that would be obtained, at the same potential, if there were no transport of that substance due to the electric field between the electrodes. The sign convention regarding current is such that the @M03920@ current is negative for the reduction of a @C00907@ or for the @O04362@ of an @A00358@, and positive for the @O04362@ of a @C00907@ or the reduction of an @A00358@. Hence the @M03920@ current may tend to either increase or decrease the total current observed. In any event the @M03920@ current approaches zero as the @T06489@ of the @E01940@ is decreased by increasing the concentration of the @S06149@, and hence the @C01245@