Using the standard electrode potential, find out the pair between which redox reaction is not feasible. E⊖ values Fe3+∕Fe2+=+0.77;I2∕I−=+0.54 Cu2+∕Cu=+0.34;Ag+∕Ag=0.80V
(a) 2Fe3++2e−→2Fe2+;E°=0.77V 2I−→I2+2e−;E°=−0.54V(signofE°isreversed) ___________________________________________ 2Fe3++2I−→2Fe2++I2;E°cel=+0.23V ___________________________________________ This reaction is feasible, since E°cell is positive. (b) Cu→Cu2++2e−;E°=−0.34V(signofE°gasbeenreversed) 2Ag++2e−→2Ag;E°=+0.80V ___________________________________________ Cu+2AG+→Cu2++2Ag;E°=+0.46V ___________________________________________ This reaction is feasible, since E°cell is positive. (c) 2Fe3++2e−→2Fe2+;E°=+0.77V Cu→Cu2++2e−;E°=−34V(signofE°isreversed) ___________________________________________ 2Fe3++Cu→Fe2++Cu2+;E°=+0.43V ___________________________________________ This reaction is feasible, since E°cell is positive. (d) Ag→Ag++e−;E°=−0.80V(signofE°isreversed) Fe3++e−→Fe2+;E°=+0.77V ___________________________________________ Ag+Fe3+→Ag++Fe2+;E°=−0.03V ___________________________________________ This reaction is not feasible, since E°cell is negative.