Which of the following statements above about ozone are not true?
a) Ozone is formed in the stratosphere.
b) Ozone is good in the troposphere and bad in the stratosphere.
c) Ozone depletion is maximum near poles.

Options

A. Only (c)
B. Only (a)
C. Only (b)
D. All of these

Answer

To determine which statements about ozone are not true, let's analyze each option step by step.

### Step 1: Analyze Statement A
**Statement A**: Ozone is formed in the stratosphere.
- **Explanation**: This statement is true. Ozone (O₃) is primarily formed in the stratosphere through a chemical reaction between ultraviolet (UV) light from the sun and oxygen molecules (O₂). The UV light splits the O₂ molecules, and the free oxygen atoms then react with other O₂ molecules to form ozone.

### Step 2: Analyze Statement B
**Statement B**: Ozone is good in the troposphere and bad in the stratosphere.
- **Explanation**: This statement is not true. Ozone is beneficial in the stratosphere because it forms the ozone layer, which protects living organisms from harmful UV radiation. However, ozone is considered a pollutant at ground level (in the troposphere) because it can cause respiratory problems and other health issues. Therefore, this statement is incorrect.

### Step 3: Analyze Statement C
**Statement C**: Ozone depletion is maximum near poles.
- **Explanation**: This statement is true. Ozone depletion is indeed more pronounced near the poles, particularly in Antarctica. The cold temperatures in these regions contribute to the formation of polar stratospheric clouds, which facilitate the chemical reactions that lead to ozone depletion.

### Conclusion
Based on the analysis:
- Statement A is true.
- Statement B is not true.
- Statement C is true.

Thus, the statement that is not true is **Statement B**.

### Final Answer
The statement that is not true about ozone is **b) Ozone is good in the troposphere and bad in the stratosphere.**

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