One free radical of chlorine can destroy molecules of ozone:

Options

A. 100
B. 500
C. 250
D. 1000

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks how many ozone molecules can be destroyed by one free radical of chlorine. To answer this, we need to understand the mechanism of ozone depletion by chlorine radicals.

2. **Chlorofluorocarbons (CFCs)**: Chlorofluorocarbons are compounds that release chlorine radicals when they are broken down by ultraviolet (UV) light in the stratosphere.

3. **Formation of Chlorine Radicals**: When UV light hits a CFC molecule (e.g., CF2Cl2), it breaks down the molecule and releases a chlorine atom (Cl•). The remaining part of the CFC molecule is a stable compound (CF2Cl).

4. **Reaction with Ozone**: The released chlorine radical (Cl•) reacts with ozone (O3) in the ozone layer. The reaction can be summarized as follows:
- Cl• + O3 → ClO + O2
In this reaction, the chlorine radical reacts with ozone, pulling away one oxygen atom and forming chlorine monoxide (ClO) and molecular oxygen (O2).

5. **Regeneration of Chlorine Radical**: The chlorine monoxide (ClO) can react with a free oxygen atom (O) to regenerate the chlorine radical:
- ClO + O → Cl• + O2
This means that the chlorine radical is not consumed in the reaction; it can continue to react with more ozone molecules.

6. **Chain Reaction**: Since one chlorine radical can regenerate itself and continue to react with multiple ozone molecules, it can destroy a significant number of ozone molecules. Studies have shown that one chlorine radical can destroy over 1000 ozone molecules before it is deactivated.

7. **Conclusion**: Therefore, the answer to the question is that one free radical of chlorine can destroy more than 1000 molecules of ozone.

### Final Answer:
One free radical of chlorine can destroy more than 1000 molecules of ozone.

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