Biogas consists of

Options

A. `CO_(2)`, ethane, hydrogen, hydrogen sulphide
B. `CO_(2)`, methane, hydrogen, hydrogen sulphide
C. CO, ethane, hydrogen, hydrogen sulphide
D. CO, methane, hydrogen, hydrogen sulphide

Answer

### Step-by-Step Solution:

1. **Understanding Biogas Composition**: Biogas is a mixture of gases produced by the anaerobic digestion of organic matter, primarily from biological waste such as cow dung.

2. **Identifying Key Components**: The main components of biogas include:
- Methane (CH₄)
- Carbon dioxide (CO₂)
- Hydrogen (H₂)
- Hydrogen sulfide (H₂S)

3. **Analyzing the Options**: The question provides four options regarding the composition of biogas:
- Option 1: Carbon dioxide, ethane, hydrogen, hydrogen sulfide
- Option 2: Carbon dioxide, methane, hydrogen, hydrogen sulfide
- Option 3: Carbon monoxide, ethane, hydrogen, hydrogen sulfide
- Option 4: Carbon dioxide, methane, hydrogen, hydrogen sulfide

4. **Eliminating Incorrect Options**:
- Ethane (C₂H₆) and carbon monoxide (CO) are not significant components of biogas.
- Therefore, options 1 and 3 can be eliminated.

5. **Confirming the Correct Option**:
- Both option 2 and option 4 contain carbon dioxide, methane, hydrogen, and hydrogen sulfide. However, option 4 is a repetition of option 2, which confirms that option 2 is indeed correct.

6. **Conclusion**: The correct answer is that biogas consists of carbon dioxide, methane, hydrogen, and hydrogen sulfide.

### Final Answer:
Biogas consists of carbon dioxide, methane, hydrogen, and hydrogen sulfide (Option 2).

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