S.L Miller's closed flask contained

Options

A. `CH_4`
B. `NH_3` and water vapours
C. `H_2`
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding the Experiment**: S.L. Miller conducted an experiment in 1952 to simulate the conditions of early Earth and to investigate the origin of life. The goal was to see if organic molecules could be formed from inorganic substances.

2. **Setting Up the Closed Flask**: In the experiment, Miller used a closed flask system to create a controlled environment. This flask contained a mixture of gases that were believed to be present in the primitive atmosphere of Earth.

3. **Identifying the Gases Used**: The gases included:
- Water vapor (H2O)
- Methane (CH4)
- Ammonia (NH3)
- Hydrogen (H2)

4. **Simulating Lightning**: To simulate the energy from lightning that could have driven chemical reactions on early Earth, Miller used electrodes to create electrical sparks in the gas mixture.

5. **Collecting the Results**: After running the experiment, Miller analyzed the contents of the flask and found that organic molecules had formed as a result of the reactions. This demonstrated that inorganic molecules could be converted into organic molecules under the right conditions.

6. **Conclusion**: The correct answer to the question is that S.L. Miller's closed flask contained CH4 (methane), NH3 (ammonia), H2 (hydrogen), and H2O (water vapor). Therefore, all of the above gases were present in the flask.

**Final Answer**: S.L. Miller's closed flask contained CH4, NH3, H2, and H2O.

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