Which of the following is being used as source of hydrogen gas needed to manufacture fertillisers ?

Options

A. biogas
B. natural gas
C. coal gas
D. petroleum gas

Answer

To determine which source is used to obtain hydrogen gas for the manufacture of fertilizers, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Requirement**: We need to find out which source provides hydrogen gas necessary for fertilizer production.

2. **Consider the Options**: The options typically include sources like biogas, natural gas, coal, and petroleum.

3. **Understand Biogas**: Biogas is produced from the anaerobic digestion of organic matter, such as sewage or agricultural waste. It primarily contains methane (60-70%), hydrogen sulfide, and carbon dioxide.

4. **Hydrogen Production from Biogas**: The hydrogen gas needed for fertilizers can be derived from biogas. Specifically, the methane in biogas can undergo a process called steam reforming, where it reacts with steam (water) to produce hydrogen gas and carbon dioxide.

5. **Conclusion**: Since biogas is a mixture that includes methane and can be used to produce hydrogen gas, it is the correct answer. Therefore, biogas is the source of hydrogen gas needed for the manufacture of fertilizers.

### Final Answer:
**Biogas is used as the source of hydrogen gas needed to manufacture fertilizers.**

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