Question

In a galvanic cell, the salt bridge
(i) does not participate chemically in the cell reaction
(ii) stops the diffusion of ions from one electrode to another
(iii) is necessary for the occurrence of the cell reaction
(iv) ensures mixing of the two electrolytic solutions.

• A. (i) and (iii) only
• B. (i) and (ii) only
• C. (iii) and (iv) only
• D. All of these

Answer 1

The correct option is B (i) and (ii) only

• A salt bridge, in electrochemistry, is a laboratory device used to connect the oxidation and reduction half cells of a galvanic cell(voltaic cell), a type of elctrochemical cell. It maintains electrical neutrality within the internal circuit, preventing the cell from rapidly running its reaction to equilibrium. If no salt bridge were present, the solution in one half cell would accumulate negative charge and the solution in the other half cell would accumulate positive charge as the reaction proceeded, quickly preventing further reaction, and hence production of electricity.
  
• Salt bridge keeps the solutions in two half-cells electrically neutral. It prevents transference or diffusion of the ions from one half-cell to the other.