Biogas primarily consists of ________ and carbon dioxide.
- Hydrogen
- Methane
- Oxygen
- Nitrogen
Answer: Methane
Biogas (from anaerobic digestion of organic waste) contains 50-75% methane (CH₄), a clean fuel. Promoted under GOBAR-DHAN scheme for rural energy and waste management. [[MNRE Reports, NCERT Chemistry Class 11]]