Question- (a) In your routine analysis of lake water collected near the bottom at pH 7, you find the following concentrations. Use one of them to calculate the Esys or Pe.

Given {Fe3+} = 1.2 x 10^-7 M, {Fe2+} = 4.42 x 10^-9 M, {Mn2+} = 4.7 x 10^-7 M, and pH=6.5

For the reduction: Fe3+ + e- <------> Fe2+ E^o= 0.769V

For the reduction: MnO2(s) + 2e- + 4H+ <-----> Mn2+ + 2H2O E^o= 1.227V

For the reduction: O2(aq) + 4e- + 4H+ <--------> 2H2O E^o= 1.268V

(b) You can use Esys or Pe to find other components of system. From your results above, find the oxygen concentration in the lake bottom water.

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