What is the standard electrode potential (Eo) for the reduction of ClO3- to Cl-?

The standard electrode potential for the reduction of chlorate ions (ClO3-) to chloride ions (Cl-) is +1.45 V, which indicates that this reduction is a thermodynamically favorable process under standard conditions.

In electrochemistry, the standard electrode potential, denoted as E°, provides insight into the tendency of a species to gain electrons (be reduced). A positive value signifies that the reduction is likely to occur, as it has a greater tendency to gain electrons compared to the standard hydrogen electrode (which is defined as 0 V).

For the reduction of ClO3- to Cl-, the half-reaction can be represented as follows:

ClO3- + 6 H+ + 5 e- → Cl- + 3 H2O

This reaction occurs in an acidic medium and the involvement of multiple protons and electrons indicates its complexity. The relatively high positive potential of +1.45 V suggests a strong driving force for the reaction, making it effective in various electrochemical applications, including disinfection processes.

By understanding the significance of the standard electrode potential, it becomes evident why this particular value reflects the favorable nature of the reduction of chlorate to chloride in electrochemical contexts.