Question

Why are the saturated solutions of electrolytes for the salt bridge prepared in agar-agar jelly or gelatin?

(a) The jelly acts as an electrolyte

(b) It helps the electrolytes to mix with the contents of the half cells

(c) It helps maintain the electrical polarity between the two half-cell solutions

(d) It keeps the electrolyte in semi-solid phase and prevents it from mixing with the two half-cell solutions

This question was addressed to me by my college director while I was bunking the class.

Enquiry is from Electrochemical Cells in chapter Electrochemistry of Chemistry – Class 12

Answer 1

Right option is (d) It keeps the electrolyte in semi-solid phase and prevents it from mixing with the two half-cell solutions

Easiest explanation: The salt bridge connects the two half-cell solutions to complete the circuit of the electrochemical cell. The electrolytes of the salt bridge are generally prepared in agar-agar or gelatin so that the electrolytes are kept in a semi-solid phase and do not mix with the half-cell solutions and interfere with the electrochemical reaction.