Question

A salt bridge:
(A)- is not used in galvanic cell
(B)- completes the circuit
(C)- increases the rate of reaction
(D)- provides an easy handle to carry the cell
(E)- None of these

Answer 1

Hint A salt bridge is used in electrochemical reactions. In order to understand the use of salt bridges, you can construct an electrochemical cell reaction like for example a galvanic cell. As the name suggests, salt bridge is used as a bridge between the two solutions kept at anode and cathode. It consists of highly soluble ions like potassium nitrate etc.

Complete answer:
Electrochemistry is the branch of physical chemistry that mainly deals with the relationship between electricity and identifiable chemical change.
Electrochemical reaction is a chemical reaction in which current is externally supplied or produced through a spontaneous chemical reaction.
Chemical reactions where electrons are directly transferred between the constituent molecules or atoms are called oxidation-reduction or rather redox reactions.
A salt bridge is used in chemical reactions where the anode solution is different from a cathode solution. In this case salt bridge is used to complete the circuit so that there is passage of current and hence chemical reaction takes place.

Therefore, the correct answer is option (B).

Note: The electrochemical reactions in which there is a common electrolyte and the electrodes are dipped in a common solution, we do not use a salt bridge. This is because the circuit is complete and there is no need for a connection in the form of salt bridge.