What is the ratio of `CH_(4)` in biogas ?

Options

A. `1:2`
B. `2:2`
C. `2:1`
D. `3:1`

Answer

To determine the ratio of methane (CH₄) in biogas, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Biogas Composition**: Biogas is primarily composed of methane (CH₄) and carbon dioxide (CO₂), along with trace amounts of other gases.

2. **Identify the Main Components**: The main components of biogas are:
- Methane (CH₄)
- Carbon dioxide (CO₂)
- Trace gases (like hydrogen sulfide, ammonia, etc.)

3. **Determine the Percentage of Methane**:
- Methane typically constitutes about 50-70% of biogas.
- Carbon dioxide makes up about 30-40% of biogas.

4. **Calculate the Ratio**:
- If we take the average values, we can estimate:
- Methane (CH₄): 60%
- Carbon dioxide (CO₂): 40%
- This gives us a ratio of methane to carbon dioxide of approximately 3:2.

5. **Expressing the Ratio**:
- To express the ratio of methane (CH₄) in biogas, we can say that for every 3 parts of methane, there are about 1 part of carbon dioxide.
- Therefore, the ratio of methane in biogas can be simplified to approximately 3:1 when considering the presence of other trace gases.

6. **Final Conclusion**:
- The ratio of CH₄ in biogas is approximately 50-75%, with a common representation of 3:1 when compared to other gases.

### Final Answer:
The ratio of CH₄ in biogas is approximately 3:1, with methane constituting about 50-75% of the total gas composition.

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