Equilibrium values of O and R can only be maintained during a cyclic voltammetry experiment if both O and R are stable on the experimental time scale. For example, if the reduction of O to R is followed by the conversion of R to P, then more R must be generated to compensate for the loss of R. Therefore, the rate of reduction increases and Epc moves to a more positive value. In addition, ipa/ipc is less than unity (since only a fraction of the molecules that were reduced on the forward scan are available for reoxidation on the reverse scan). The value of the current function can also be affected by chemical reactions following electron transfer.