Why is it necessary to use a salt bridge in a galvanic cell ?

Explanation

### Step-by-Step Solution

1. **Understanding the Galvanic Cell**: A galvanic cell consists of two half-cells, one acting as the anode and the other as the cathode. Each half-cell contains an electrolyte solution and an electrode.

2. **Role of the Salt Bridge**: The salt bridge is a crucial component of a galvanic cell. It connects the two half-cells and allows for the flow of ions between them.

3. **Maintaining Electrical Neutrality**: As the redox reaction occurs in the galvanic cell, there is a buildup of positive ions in the anode compartment and negative ions in the cathode compartment. This imbalance can disrupt the flow of electrons and halt the reaction. The salt bridge allows ions to flow, which helps to maintain electrical neutrality in both compartments.

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