delta_G = -nFE connects electrochemistry to thermodynamics. delta_G_standard = -nFE_standard. Since delta_G = delta_H - Tdelta_S, and (partial E/partial T)_P = delta_S/(nF), we get: delta_S = nF(dE/dT)_P (temperature coefficient of EMF). delta_H = delta_G + Tdelta_S = -nFE + nFT(dE/dT). If dE/dT > 0, the reaction absorbs heat from surroundings (endothermic contribution). If dE/dT = 0, delta_G = delta_H (no entropy change). The relationship delta_G_standard = -RT*ln(K) = -nFE_standard connects all three: equilibrium, thermodynamics, and electrochemistry.