General Chemistry

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Calculating Free Energy of a Nickel Iron Battery


A nickel iron battery has a $20.0 \textrm{ g NiO(OH)}$ cathode, a $15.0 \textrm{ g Fe}$ anode, and a $\textrm{KOH}$ electrolyte. The cell potential is $1.37 \textrm{ V}$ at $25 °C$ and uses the following half reactions.

$$\textrm{Fe}_{(s)}+2\textrm{OH}^-_{(aq)}\rightarrow \textrm{Fe(OH)}_{2(s)} + 2e^-$$

$$\textrm{NiO(OH)}_{(s)}+ \textrm{H}_2\textrm{O}_{(l)} + e^- \rightarrow \textrm{Ni(OH)}_{2(s)}+ \textrm{OH}^-_{(aq)}$$