Why does the electrochemical cell stop working after some time ?

Explanation

### Step-by-Step Solution

1. **Understanding Electrochemical Cells**: Electrochemical cells convert chemical energy into electrical energy through redox reactions. They consist of two electrodes: anode (where oxidation occurs) and cathode (where reduction occurs).

2. **Electron Flow**: In an electrochemical cell, electrons flow from the anode to the cathode. This flow is essential for the cell to generate electrical energy.

3. **Depletion of Reactants**: Over time, the reactants involved in the electrochemical reactions are consumed. For example, the materials at the anode and cathode undergo oxidation and reduction, respectively. Once these materials are depleted, there are no more reactants to sustain the reactions.

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