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Kw of water from reduction potentials

a). Give the cell diagram notation of the electrochemical cell that could be used to determine experimentally the dissociation constant (Kw) of water. The standard reduction potential for

O2 + 2H2O + 4 e-------> 4OH- is + 0.40V

For other half-reactions, use a textbook. Calculate E for this cell.

b). Use your value from part a) to calculate the dissociation constant at 298K.

Solution Preview

We need H2O ----> H+ + OH- E = ?

O2 + 2H2O + 4 e-------> ...

Solution Summary

The dissociation constant of water is calculated from electrochemical diagrams.