When electric current is passed through a conducting solution, there is a change of colour of the solution. This indicates

Options

A. the chemical effect of current
B. the heating effect of current.
C. the magnetic effect of current.
D. the lightning effect of current.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question states that when electric current is passed through a conducting solution, there is a change in color of the solution. We need to determine what this indicates.

2. **Identifying the Phenomenon**: When electric current flows through a conducting solution, it can lead to various effects. One of the observable effects is a change in color of the solution.

3. **Chemical Reaction**: The change in color suggests that a chemical reaction is occurring in the solution. This is because the color change is typically due to the formation of new substances or ions as a result of the current passing through the solution.

4. **Chemical Effect of Current**: The process we are observing is known as the chemical effect of electric current. This effect indicates that the electric current is causing a chemical change in the solution.

5. **Evaluating Other Effects**:
- **Heating Effect**: The heating effect of current refers to the generation of heat due to resistance in the conductor. While this can occur, it does not explain the color change.
- **Magnetic Effect**: The magnetic effect of current relates to the magnetic fields produced by electric currents, which is not relevant to the color change in the solution.
- **Lightning Effect**: The lightning effect is related to high-voltage discharges and does not pertain to the color change in a conducting solution.

6. **Conclusion**: Since the change in color is directly linked to a chemical reaction occurring due to the passage of electric current, we conclude that this indicates the chemical effect of current.

7. **Final Answer**: Hence, the correct answer is that the change in color of the solution indicates the chemical effect of electric current.

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