Miller circulated methane, ammonia, hydrogen and water vapour in air tight apparatus and passed electric discharged from electrodes at :

Options

A. `180^@ C `
B. ` 100^@ C `
C. ` 78^@ C `
D. ` 800^@ C `

Answer

**Step-by-Step Solution:**

1. **Understanding the Experiment**: The Miller experiment, conducted by Stanley Miller in 1953, aimed to simulate the conditions of early Earth to investigate the origin of life. He used a mixture of gases thought to be present in the primitive atmosphere.

2. **Identifying the Gases Used**: The gases circulated in the airtight apparatus included methane (CH4), ammonia (NH3), hydrogen (H2), and water vapor (H2O). These gases were chosen because they were believed to be abundant in the early Earth's atmosphere.

3. **Electric Discharge**: Miller passed electric discharges through the mixture of gases. This was intended to mimic lightning, which could have provided the energy necessary for chemical reactions to occur, leading to the formation of organic compounds.

4. **Temperature of the Experiment**: The experiment was conducted at a high temperature to facilitate the reactions. According to the information provided, the temperature used by Miller was 800 degrees Celsius.

5. **Conclusion**: Based on the details of the experiment and the temperature used, the correct answer to the question is 800 degrees Celsius.

**Final Answer**: The correct option is D: 800 degrees Celsius.

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