Chapter 3 Electrochemistry, Chemistry class 12 Chapter 3 Electrochemistry Chemistry, Class 12 | Page 11

Electrical resistance o It is denoted by the symbol ‘ R ’. o
The cell in which the following reactions occurs :
has E ø cell = 0.236 V at 298 K . Calculate the standard Gibbs energy and the equilibrium constant of the cell reaction .
Solution : By using the formula , ΔrG = -nFEcell = -2 X 96487 X 0.236
= - 45541.864 J mol -1 = - 45.54 KJ mol -1
Electrical resistance o It is denoted by the symbol ‘ R ’. o
It is measured in a unit called ohm ( Ω ) with the help of a Wheatstone bridge
o The electrical resistance is : 1 . Directly proportional to its length , l 2 . Inversely proportional to its area of cross section , A .