Electrochemical cells are of two types In galvanic cell,
the chemical energy of a spontaneous redox reaction is converted into electrical
work, whereas in an electrolytic cell, electrical energy is used to carry out a non-
spontaneous redox reaction The standard electrode potential for any electrode
dipping in an appropriate solution is defined with respect to standard electrode
potential of hydrogen electrode taken as zero The standard potential of the cell
can be obtained by taking the difference of the standard potentials of cathode and
anode (
(
)
o
Ecell
 = Eocathode – Eoanode)