Question

Which of the following statement(s) is/are true about $KCl$ salt bridge?

• A. $K^{+}$ will migrate towards reduction electrode
• B. $C{l}^{-}$ will migrate towards oxidation electrode
• C. It will increase the rate of reaction
• D. It connects the half cells internally

Answer 1

Answer: (A), (B), (D)

It connects the half cells internally

Salt bridge is a U–shaped inverted tube that contains a gel (paste of agar-agar powder) permeated with an inert electrolyte.
It connects two electrodes internally or connects the two solutions.
If electrodes are not connected internally, initially the cell generates electrical energy but after sometimes opposite charged ions gets accumulated around the electrode and gets polarised. Thus, the cell stops working or electron flow stops.

To avoid this situation, the electrodes need to be internally connected by salt bridge.

From the $KCl$ salt bridge, the cation $K^{+}$ will migrate toward reduction electrode (cathode).
The anion $C{l}^{-}$ will migrate toward oxidation electrode (anode).

Salt bridge does not increase the rate of the reaction.
Thus, statement (a), (b) and (d) are true.