The concentration of Iron in the galvanic (voltaic) cell Fe(s) + Mn²⁺(aq) ⟶ Fe²⁺(aq) + Mn(s) is 0.02297 M.
The Nernst equation enables us to identify the cell potential(voltage) in presence of non-standard conditions in a galvanic cell. It can be expressed by using the formula:
[tex]\mathbf{E_{cell} = E_o - \dfrac{0.059}{n} \times log \dfrac{[Fe^+]}{[Mn^{2+}]}}[/tex]
where;
Replacing the values into the above equation, we have:
[tex]\mathbf{0.78 = 0.77 - \dfrac{0.059}{2} \times log \dfrac{[Fe^{2+}]}{[0.050]}}[/tex]
[tex]\mathbf{0.78 -0.77= -0.0296\times log \dfrac{[Fe^{2+}]}{[0.050]}}[/tex]
[tex]\mathbf{log^{-1} (-0.3378) = \dfrac{[Fe^{2+}]}{[0.050]}}[/tex]
[tex]\mathbf{Fe^{2+} = (0.4594\times 0.050 )\ M}[/tex]
[tex]\mathbf{Fe^{2+} =0.02297 \ M }[/tex]
Learn more about using the Nernst equation here:
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