An electrochemical cell stops working after some time because_____

Explanation

**Step-by-Step Solution:**

1. **Understanding Electrochemical Cells**: An electrochemical cell consists of two electrodes (anode and cathode) immersed in an electrolyte. The cell generates electrical energy through redox reactions occurring at the electrodes.

2. **Role of Potential Difference**: The operation of an electrochemical cell relies on a potential difference between the two electrodes. This potential difference causes electrons to flow from one electrode to the other, generating electric current.

3. **Depletion of Reactants**: Over time, the reactants involved in the redox reactions at the electrodes get consumed. As the reactants are used up, the reactions slow down, leading to a decrease in the potential difference.

4. **Equalization of Electrode Potentials**: Eventually, the electrode potentials of both electrodes become equal. When this happens, there is no longer a driving force (potential difference) for the flow of electrons.

5. **Conclusion**: The electrochemical cell stops working when the electrode potentials equalize, meaning there is no longer a potential difference to sustain the flow of electrons.

**Final Answer**: An electrochemical cell stops working after some time because the electrode potentials of both electrodes become equal.

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