 # Electrochemistry Class 12 Notes - Chapter 3

A device that generates a potential difference between electrodes by chemical reactions is called an electrochemical cell. It comprises two electron conductors which are separated by an ionic conductor and are linked by an electron conductor. The two metallic electrodes are dipped in the electrolytic solution. The important component of this cell is an ionic conductor.

## Types Of Electrochemical Cell

Electrochemical cells are of two types. They are Galvanic cell and Electrolytic cell. These are two fundamental types of electrochemical cell.

• Galvanic cell – In a galvanic cell, spontaneous redox reaction, the chemical energy is converted into electrical energy. It is also called voltaic cell or Daniel cell.
• Electrolytic cell – In an electrolytic cell, the nonspontaneous redox reaction is carried out by electrical energy.

We can obtain the standard potential of the cell by taking the difference between the standard potentials of anode and cathode.

### Few Important Questions

1. Define and distinguish between molar conductivity and conductivity.
2. How much charge is required for the reduction of 1 mol of Al3+ to Al?
3. How much electricity is necessary for oxidation of 1 mol of H2O to O2 in coulomb.
4. Find the cell constant of 0.001M KCl solution with the following details:

T = 208 K, conductivity = 0.146 × 10–3 S cm–1, R = 1500 Ω

1. Calculate the molar conductivity for the following:

Conductivity = 0.0248 S cm–1, 0.20 M solution of KCl solution, Temperature = 298 K