Example
Example . Represent the cell in which the following reaction takes place Mg(s) + 2Ag + ( .0001M) ® Mg + ( .130M) + 2Ag(s) Calculate its E (cell) if = . V. The cell can be written as Mg ú Mg + ( .130M) úú Ag + ( .0001M) ú Ag Mg RT ln 2F Ag = . V – . log ( . V . = . V – .21V = . V. The standard electrode potential for Daniell cell is .1V. Calculate the standard Gibbs energy for the reaction: Zn(s) + Cu + (aq) ¾® Zn + (aq) + Cu(s) D r G o = – nF (cell) n in the above equation is , F = 96487 C mol – and = . V Therefore, D r G o = – × .1V × 96487 C mol – = – 21227 J mol – = – . kJ mol –