Gobar gas is :

Options

A. Foul smelling gas
B. sweet smelling gas
C. having high calorific value
D. useless

Answer

**Step-by-Step Solution:**

1. **Understanding Gobar Gas**: Gobar gas, also known as biogas, is produced from the anaerobic digestion of organic matter, particularly animal dung (gobar) and other biodegradable materials.

2. **Composition of Gobar Gas**: The main components of gobar gas include methane (CH4), carbon dioxide (CO2), and small amounts of other gases. Methane is the primary component that gives it its fuel properties.

3. **Properties of Gobar Gas**:
- It is flammable and can be used as a fuel for cooking and lighting.
- It has a high calorific value, which means it can produce a significant amount of energy when burned.

4. **Evaluating the Options**:
- **Option 1**: "Full smelling gas" - This is incorrect as gobar gas has a characteristic smell due to impurities, but it is not described as "full smelling."
- **Option 2**: "Sweet smelling gas" - This is also incorrect; gobar gas does not have a sweet smell.
- **Option 3**: "Having high calorific value" - This is correct; gobar gas is known for its high calorific value, making it an efficient fuel.
- **Option 4**: "Useless" - This is incorrect; gobar gas is very useful as a renewable energy source.

5. **Conclusion**: Based on the analysis of the options, the correct answer is that gobar gas is "having high calorific value."

**Final Answer**: Gobar gas is having high calorific value.

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