Correct Answer - Option 3 : Methane
Concept:
Biogas: The mixture of gases that are produced due to the breakdown of organic matter in the absence of oxygen is called biogas.
- The major constituent of biogas is Methane and Carbon dioxide while some traces of H2S and ammonia are also there.
- It is released when the Cow, Buffalo, and Pig manure is processed Anaerobically i.e. in the absence of Oxygen.
- Biogas can be used for Space Heating, Generation of Electricity, Fuel for Cooking, etc
| Biogas Composition |
| Sl.No. |
Compound |
Percentage |
| 1 |
Methane |
50 - 75% |
| 2 |
Carbon dioxide |
25 - 50% |
| 3 |
Nitrogen |
10 - 20% |
| 4 |
Hydrogen |
0 - 1% |
| 5 |
Hydrogen sulfide |
0 - 3% |
| 6 |
Oxygen |
0 - 0.5% |
Compressed Natural Gas (CNG): it is composed of compressed Methane and Ethane.
- It can be used in place of gasoline, diesel fuel and liquefied petroleum gas (LPG)
Explanation:
- The main constituent of both Biogas and CNG is Methane.
- So the correct option is Methane.
Note: Biogas is a Clean Renewable Energy Source and even it is Economically Friendly.
Methane is commonly known as Marsh Gas.
- Methane is the hydrocarbon having the lowest molecular mass with the chemical formula CH4.
- It is called Marsh gas because it is released in huge amounts from marshes where anaerobic bacteria decompose matter.
- It was discovered by Alessandro Volta in 1776.
- It is the main constituent of Biogas and Compressed Natural Gas (CNG).
- It is a Greenhouse gas and its global warming potential is 28 - 36 times as that of CO2.
- Paddy fields are also a huge source of Methane emissions.
