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 Miller's Experiment**: The experiment conducted by Stanley Miller in 1953 is known for simulating the conditions of early Earth to test the hypothesis of abiogenesis, which is the origin of life from non-living matter.

2. **Setup of the Experiment**: Miller used an airtight apparatus where he circulated a mixture of gases that were believed to represent the early Earth's atmosphere. The gases included methane (CH4), ammonia (NH3), hydrogen (H2), and water vapor (H2O).

3. **Creating Conditions**: The apparatus was designed to mimic the reducing atmosphere of early Earth. The reducing atmosphere is characterized by the presence of hydrogen-rich gases, which are conducive to the formation of organic molecules.

4. **Temperature and Energy Source**: The temperature in the apparatus was maintained at approximately 800 degrees Celsius. To simulate the energy sources present on early Earth, Miller passed electrical discharges (simulating lightning) through the gas mixture.

5. **Formation of Organic Molecules**: After running the experiment for a few days, Miller observed the formation of organic compounds, notably amino acids, which are the building blocks of proteins. He also noted the formation of simple sugars and other organic molecules.

6. **Conclusion**: Miller's experiment demonstrated that organic molecules could be synthesized from inorganic precursors under conditions thought to resemble those of early Earth, supporting the idea that life could have originated from simple chemical processes.

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