Question

What is the role of a salt bridge?

Answer 1

Hint : A salt bridge that acts as a bridge between two half cells is also known as ion bridge. The exchange of ions will not occur in a voltaic cell if there is no salt bridge or an ion bridge connecting the half cells.

Complete Step By Step Answer:
The role of a salt bridge in a voltaic cell is to provide a medium for the ions to transfer from one side to another.
Without the use of salt bridges, the ions will accumulate in their respective cells, thus it has to be used in order for the exchange of ions. A salt bridge helps anions to move towards anode compartment and cations to move towards cathode compartment.
The main use of a voltaic cell is to produce electricity, if no salt bridge is used in a voltaic cell, then no transfer of electrons will occur and no electricity will be produced. Thus salt bridge is one of the most important parts for the functioning of a voltaic cell.
This cell was invented by Luigi Galvani and Alessandro Volta, thus this cell is known as voltaic cell or galvanic cell. The electric current produced in this cell is due to redox reactions occurring inside the half cells.
In this cell, two thin plates of different metals are taken, one is anode and one is cathode. These two plates are dipped in an electrolytic solution which helps the metal on anode to lose electrons and form ions. The electrons that are lost by anodic metal are accepted by cathodic metal and thus the metal on cathode also forms an ion.
The flow of electrons in a voltaic cell or a galvanic cell is from anode to cathode, thus the conventional current of the cell will be from cathode to anode.

Note :
The whole voltaic or galvanic cell is made up of two half cells, in one half cell anode plate is dipped in the electrolytic solution and in the other half cell cathode is dipped in the electrolytic solution. As the name suggests, a salt bridge connects both the half cells which is necessary for the electric current to be produced. A salt bridge is also known as an ion bridge as ions are formed due to the passing of the electrons through that bridge.