Miller successfully demostrated formation of amino-acids by electric discharge in the mixture of:

Options

A. Methane, ammonia, oxygen, nitrogen
B. Hydrogen, methane, ammonia, water vapour
C. Ammonia, methane, carbon-dioxide, oxygen
D. Hydrogen, oxygen, water vapour, nitrogen

Answer

To answer the question about the mixture used by Miller to demonstrate the formation of amino acids through electric discharge, we can break down the solution into the following steps:

### Step-by-Step Solution:

1. **Understanding Miller's Experiment**:
- Stanley Miller conducted an experiment in 1953 to simulate the conditions of early Earth and test the hypothesis of abiogenesis (the origin of life from non-living matter).

**Hint**: Think about what Miller was trying to recreate in his experiment.

2. **Identifying the Components of the Mixture**:
- Miller used a mixture of gases that were believed to be present in the early Earth's atmosphere. The primary gases used in his experiment were methane (CH₄), ammonia (NH₃), hydrogen (H₂), and water vapor (H₂O).

**Hint**: Recall the gases that are commonly associated with the early Earth atmosphere.

3. **Electric Discharge**:
- Miller applied electric discharge (simulating lightning) to this mixture to provide energy, which facilitated chemical reactions that led to the formation of amino acids.

**Hint**: Consider how energy sources might have influenced chemical reactions in early Earth conditions.

4. **Analyzing the Options**:
- Now, we need to evaluate the provided options to identify which one correctly lists the gases used in Miller's experiment:
1. Methane, Ammonia, Oxygen, Nitrogen
2. Hydrogen, Methane, Ammonia, Water vapor
3. Ammonia, Methane, Carbon Dioxide, Oxygen
4. Hydrogen, Oxygen, Water vapor, Nitrogen

- The correct mixture includes hydrogen, methane, ammonia, and water vapor. Therefore, option 2 is the correct answer.

**Hint**: Look for the combination of gases that aligns with Miller's findings.

5. **Conclusion**:
- The correct answer to the question is that Miller successfully demonstrated the formation of amino acids by electric discharge in the mixture of **Hydrogen, Methane, Ammonia, and Water vapor**.

### Final Answer:
Miller successfully demonstrated the formation of amino acids by electric discharge in the mixture of **Hydrogen, Methane, Ammonia, and Water vapor** (Option 2).