Question

In an electrochemical process, a salt bridge is used:
A) To maintain electrical neutrality in each solution
B) To complete the external circuit so that current can flow for long time
C) To mix the solution of anodic and cathodic compartment
D) To supply voltage

Answer 1

In electrochemistry salt bridge is a device which is used to connect the two half cells oxidation half-cell and reduction half-cells which can be of either galvanic cell or voltaic cell which is a type of electrochemical cell. It function is to maintains electrical neutrality inside the circuit so that reactions do not occur rapidly to form equilibrium in the cell

Complete step by step answer:
Now we will discuss about salt bridge;
A salt bridge is a device which is used to make connections between the oxidation half-cell and the reduction half-cells of a galvanic cell (Voltaic cell, Daniel cell), which is a type of electrochemical cell. Its basic function is to maintain electrical neutrality in the internal circuit, which helps in preventing the cell from working rapidly to attain equilibrium of reaction. In the absence of a salt bridge there is accumulation of positive charge in one half cell and negative charge in the other half cell which prevents the reaction and production of electricity. Therefore it helps in completing the circuit thereby allowing the flow of charges and production of electricity. It allows flowing of current by completing the internal circuit.
Usually salt bridge consists of strong electrolyte made up of ions. For example ${\text{AgN}}{{\text{O}}_{\text{3}}}{\text{, KCl}}$ etc.
Therefore for the given question, the salt bridge is used to maintain electrical neutrality in each solution by allowing the flow of charges.

So, the correct answer is Option A.

Note: One of the example of salt bridge is ${\text{KCl}}$which provides ions to maintain the neutrality in the circuit, positive ${{\text{K}}^ + }$ions and negative ${\text{C}}{{\text{l}}^ - }$are equal in composition so that positive charge is balanced by the negative charge and neutrality is maintained.