Correct Answer – B
A salt bridge can be any medium through which ions can slowly pass . A salt bridge can be made by bending a piece of glass tune into the shape of a ‘U’ , filling it with a hot saturated salt `//5%` agar-agar solution, and allowing it to cool. The cooled mixture ‘sets’ to the consistency of firm gelatin. As a result, the solution does are still able to move. A salt bridge serves three functions :
(a) It allows electrical contact between the two solutions.
(b) It prevents mixing of the electrode solutions.
(c ) It maintains the electrical neutrality in each half-cell as ions flow into and out of the salt bridge.