Heat of Reaction in an Electrochemical Cell
Let n Faraday charge flows out of a cell of emf E, then
Gibbs – Helmholtz equation from thermodynamics may be given as
From equation (i) and (ii) we get,
where = Temperature coefficient of cell
Case I: When = 0, then
Case II: When > 0, then i.e. process inside the cell is endothermic.
Case III: When < 0, then i.e., process inside the cell is exothermic.