Chapter 24, Problem 10STP

Interpretation Introduction

Interpretation:

The function of salt bridge is to be explained.

Concept introduction:

A salt bridge is an inverted U-shaped tube which containing the concentrate solution of inert electrolyte.

Answer to Problem 10STP

The important function of the salt bridge is:

1. The electrical circuit inside an electrochemical cell becomes complete with the help of salt bridge.
2. Salt bridge maintains the electrical neutrality during the oxidation and reduction processes which carry out at anode and cathode electrode respectively.

Explanation of Solution

1. The salt bridge is used to connect two solutions of the half cells and their electrodes which are connected by a wire. Salt bridge completes the circuit.
2. In the two half-cells, salt bridge prevents the accumulation of charges. It provides a passage through which charge can flow in the internal circuit. When concentration of positive ion increases, the number of chloride ion migrates from salt bridge to anode half cell. The excess negative charge is neutralized by additional sulphate ion in the cathode half cell.

Conclusion

Generally, salt bridge is used to conserve the electrical neutrality during the electrochemical reaction and completes the electrical circuit.