Electrical Engineering ⇒ Topic : Introduction Chemical Effects of Electric Current

Introduction

The reader is well acquainted with the passage of electric current through metallic conductors,e.g., copper, aluminium etc. In such conductors, current conduction is due to the movement of free electrons and there is no chemical or physical change except the rise in temperature. However,conduction of current through *certain salt solutions is quite different. Such liquids provide a large number of oppositely charged atoms (called ions) and are known as electrolytes e.g., acids (H₂S0₄,HC₁ etc.), solutions of inorganic compounds (NaC₁, CuSO₄, AgNO₃ etc.), hydroxides of metals (KOH, NaOH etc). In an electrolyte, conduction is due to the movement of ions (an electrolyte hasno free electrons) and chemical changes occur so long as the conduction takes place. Thus passage of electric current through an electrolyte causes chemical changes i.e. electrical energy is converted into chemical energy. The converse of this is also true i.e., we can produce electrical energy from chemical energy. In this chapter, we shall study about the close relationship between electrical energy and chemical energy