Miller performed experiment to prove molecular evolution of life. Which molecule was not present in Miller's experiment

Options

A. Ammonia
B. Methane
C. Oxygen
D. Hydrogen.

Answer

**Step-by-Step Solution:**

1. **Understanding Miller's Experiment**: Stanley Miller conducted an experiment in 1953 to simulate the conditions of early Earth to understand how organic compounds could form from inorganic precursors.

2. **Conditions Simulated**: Miller created an environment in a flask that mimicked the primitive Earth's atmosphere. This included high temperatures and pressures.

3. **Gases Used in the Experiment**: The gases that Miller included in his experiment were:
- Methane (CH4)
- Ammonia (NH3)
- Hydrogen (H2)
- Water vapor (H2O)

4. **Absence of Oxygen**: A crucial aspect of Miller's experiment was that it did not include free oxygen (O2). The primitive Earth atmosphere was thought to be reducing, meaning it lacked free oxygen, which is essential for oxidation reactions.

5. **Conclusion**: Therefore, the molecule that was not present in Miller's experiment is **oxygen (O2)**.

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