Which of the following is not a greenhouse gas?

Options

A. Water vapour
B. Methane
C. Carbon Dioxide
D. Calcium Carbonate

Answer

To determine which of the following is not a greenhouse gas, we need to analyze each option provided:

1. **Understanding Greenhouse Gases**: Greenhouse gases are substances that trap heat in the atmosphere and contribute to the greenhouse effect, which is essential for maintaining the Earth's temperature.

2. **Evaluating the Options**:
- **Water Vapor**: This is a significant greenhouse gas that contributes to the greenhouse effect by trapping heat in the atmosphere.
- **Methane**: This is another potent greenhouse gas, much more effective at trapping heat than carbon dioxide, although present in smaller quantities.
- **Carbon Dioxide (CO2)**: This is one of the most well-known greenhouse gases, primarily produced by burning fossil fuels and deforestation.
- **Calcium Carbonate**: This is a compound that is not a gas; it is a solid mineral often found in rocks and shells. It does not contribute to the greenhouse effect.

3. **Conclusion**: Among the options provided, calcium carbonate is not a greenhouse gas. Therefore, the answer to the question is calcium carbonate.

**Final Answer**: Calcium Carbonate

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