Electrochemistry is the branch of chemistry that deals with the chemical changes produced by electric current and the electricity generation by chemical changes. An electrochemical cell consists of 2 metallic conductors known as electrodes in contact with an ionic conductor i.e. an electrolyte. The electrolyte and the electrode comprise an Electrode Compartment. An Electrolytic Cells are those in which a non-spontaneous reaction is controlled by an external source of electric current. Th Galvanic Cells generate electric current due to spontaneous cell reaction. In a galvanic cell, the cathode is + ve w.r.t. the anode whereas, in an electrolytic cell the anode is + ve w.r.t. the cathode. The decomposition of electrolyte solution by passing current, resulting in the liberation of gases or metal deposition at electrodes is termed as electrolysis. In an Electrolytic cell, the electrical energy is converted into chemical energy.
Q.1: What are the important topics in electrochemistry?
Sol: Electrochemistry does fall under the important topics, which help you in scoring good in JEE. Following are the concepts that should be studied carefully:
- Electrolysis and electrolytic cell
- Daniel cell
- Electrochemical series
- Electrode Potential
- Arrhenius Theory of Electrolytic Dissociation
- Faradays law of Electrolysis
- Nernst equation
- Electrolytic Conduction
- Kohlrauschs Law
- Concentration cells
- Application of Electrolysis
Q.Find the charge in coulomb (C) on 1 (g)gram ion of N3-.
Charge on one ion of N3-in Coulomb = 3 × 1.6 × 10-19C
Thus, charge on 1 gram (g) ion of N3-in Coulomb = 3 × 6.02 × 1023× 1.6 × 10-19= 2.89 × 105C.