In the context of alternative sources of energy, ethanol as a viable bio-fuel can be obtained from —
- Potato
- Rice
- Sugarcane
- Wheat
Explanation
Option (c) is correct
- Ethanol is commercially produced mainly from sugarcane/molasses in India. Ethanol (C₂H₅OH) is a renewable, flammable, colourless bio-alcohol used as a transport fuel.
- Production modes: Produced through fermentation of sugars/starches or by ethylene hydration.
- Energy Characteristics: Ethanol has a high-octane rating but is 27% less energy-dense than petrol.
- Dual Role: It serves as a petrol additive and as a standalone fuel (E85, E100) in flex-fuel cars.
- Non-Fuel Use: Ethanol is also used in sanitisers, perfumes, beverages, and industrial solvents.
- By-Products: Distillers’ dried grains (DDGS) from grain ethanol are reused as animal feed.
