Question

Saturated solution of $KNO_3$ is used to make -salt-bridge- because

• A. velocity of $K^+$ is greater than that of $NO^- _3$
• B. velocity of $NO^- _3$ is greater than that of $K^+$
• C. velocities of both $K^+$ and $NO^- _3$ are nearly the same
• D. $KNO_3$ is highly soluble in water

Answer 1

Answer: (C)

velocities of both $K^+$ and $NO^- _3$ are nearly the same

Answer 2

One of the requirement for electrolyte used in salt-bridge is, both cation and anion must have comparable size so that they migrate towards electrodes of opposite polarity at comparable speeds.