By comparing standard reduction potentials, we can compare the reduction and oxidation powers of elements or ionic species. Some standard reduction potential values are given in Table 1.
In a galvanic cell, usually a salt bridge is used. What is the most likely purpose of this?
|A|| To conduct electricity|
|B|| To prevent corrosion|
|C|| To regulate electricity|
|D|| To maintain neutrality in the half-cells|
Ans. D Even though a salt bridge allows an electrical connection between the two half-cells in a galvanic cell, the function of a salt bridge is not to conduct electricity. So Choice A is ruled out. Choice B makes no sense. The salt bridge does not control the voltage. The function of a salt bridge is to maintain electrical neutrality in the half-cells so that excess buildup of charge will not occur in the half-cells. If excess charge builds up in the half-cells, the reaction will slow down and quickly die out.