Consider the following standard reduction potentials. ${\mathrm{Fe}}^{3+}\left(\mathrm{aq}\right)+{\mathrm{e}}^{-}\rightleftharpoons {\mathrm{Fe}}^{2+}\left(\mathrm{aq}\right),{\mathrm{E}}^0=0.77\mathrm{V}$, ${\mathrm{H}}_2{\mathrm{O}}_2\left(\mathrm{aq}\right)+2{\mathrm{e}}^{-}\rightleftharpoons 2{\mathrm{OH}}^{-}\left(\mathrm{aq}\right),{\mathrm{E}}^0=0.88\mathrm{V}$. For the voltaic cell reaction below, calculate the Fe²⁺ concentration (in M) that would be needed to produce a cell potential equal to 0.16V at 25°C when  $\left[{\mathrm{OH}}^{-}\right]=0.1\mathrm{M},\left[{\mathrm{Fe}}^{3+}\right]=0.5\mathrm{M}\text{ and }$
$\left[{\mathrm{H}}_2{\mathrm{O}}_2\right]=0.35\mathrm{M};\left)2{\mathrm{Fe}}^{2+}\right(\mathrm{aq})+{\mathrm{H}}_2{\mathrm{O}}_2(\mathrm{aq})\rightleftharpoons 2{\mathrm{Fe}}^{3+}(\mathrm{aq})+2{\mathrm{OH}}^{-}(\mathrm{aq}$