Calculate the standard Gibbs free energy of Zn(s)+Cu2+(aq)⟶Zn2+(aq)+Cu(s˙)
-91 FEcell
-2 FEcell
-3 FEcell
-4 FEcell
ΔrG=−nFEcell ∵ n=2, so ΔrG=−2FEcell