Impact of NON-Standard Conditions on Voltaic Cells Using NERST Eqn.

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Impact of NON-Standard Conditions on Voltaic Cells Using NERST Eqn

Help ! Help! My battery is dead! As redox rxn progresses, concentrations of ions in anode + cathode cell changes. Eventually, flow of e- stops, E = 0 and … cell is dead. Cell will discharge e- until it reaches equilibrium, termed the dead cell, Q = K and E = 0. At equilibrium,  G = 0.

Effect of [Concentration] on E cell NERST Eqn takes into account solns NOT at 1M: Gibbs Free Energy  G Gas Constant R (8.31 J/mol-K) Temperature in (K)elvin Mol n Faraday’s ConstantF Cell PotentialE cell Reaction Quotient Q [Products]/[Reactants]

The NERST Equation Use NERST to explore ion concentration changes during redox 25 °C

Sample Exercise p. 850 Sample Exercise p. 850

TAKE HOME MESSAGE p. 850 Increasing [reactants] or decreasing [products] results in HIGH E! Decreasing [reactants] or increasing [products] results in LOW E! In comparison with E at Standard Conditions.