87.10 Application of EMF and electrode potential 7.10.4. Advance of reaction(equilibrium constants) ∠G=0 At equilibrium ∠G=-nFE o(Fe”+/Fe2)=q(2/r) Fe3++I→>Fe2++%2I p(Fere)-p(12/)=7 T RTa o(Fe+/Fe2+)=e(Fe+/Fe2*)+In-Fe' nF RT, aF2 a, RT In K F nF (2I)=°(121,a17.10.4. Advance of reaction (equilibrium constants) 3 2 2 2 2 3 3 2 I Fe 2 I Fe Fe I Fe I (Fe / Fe ) (I / I ) ln ln ln ln a RT RT a a nF a nF a RT RT a a E K nF a a nF   + − + + + − + + − − = − = = 3 2 3 2 3 2 Fe Fe (Fe / Fe ) (Fe / Fe ) ln RT a nF a   + + + + + + = +2 I 2 2 I (I / I ) (I / I ) ln RT a nF a   − − − = + 3 2 2   (Fe / Fe ) (I / I ) + + − = Fe3+ + I ¯→ Fe2+ + ½ I2 At equilibrium §7.10 Application of EMF and electrode potential G nFE = − G = 0