UPSC Prelims 2025 Q45: Science & Technology – Energy & Environment
Consider the following substances:
I. Ethanol
II. Nitroglycerine
III. Urea
Coal gasification technology can be used in the production of how many of them?
- (a) Only one
- (b) Only two
- (c) All the three
- (d) None
Answer: (b) Only two
Explanation
Products of coal gasification
Coal gasification turns coal into syngas, a mix of carbon monoxide and hydrogen.
Syngas is then used to make fuels and chemicals.
| Substance | Made through coal gasification? | Route |
|---|---|---|
| I. Ethanol | Yes | Syngas to methanol and ethanol |
| II. Nitroglycerine | No | An explosive made from glycerol with nitric and sulphuric acids |
| III. Urea | Yes | Hydrogen from syngas to ammonia, then to urea |
Coal gasification in India:
| Feature | Detail |
|---|---|
| Target | Gasify 100 million tonnes of coal by 2030 |
| Example | Talcher Fertilizers, Odisha: urea from coal |
| Other products | Methanol, dimethyl ether, synthetic natural gas, hydrogen |
| Benefit | Cleaner use of India's high-ash coal; fewer imports |
So two of the three substances can be produced.
Answer: (b) Only two.
Why each option is right or wrong
- (a) Incorrect. Both ethanol and urea can be produced, so more than one.
- (b) CORRECT. Ethanol and urea can be made through coal gasification; nitroglycerine is not.
- (c) Incorrect. Nitroglycerine is made from glycerol, not from coal gasification.
- (d) Incorrect. Two of the substances can be produced.
Key point
Coal gasification gives syngas (CO + hydrogen), used for methanol, ethanol, ammonia and urea, and synthetic natural gas; India targets 100 million tonnes by 2030.
Remember
Coal gasification: ethanol and urea, yes.
Common mistakes
- Thinking coal gasification gives only fuel gas.
- Not linking urea to ammonia made from syngas hydrogen.
- Counting nitroglycerine because its name has 'nitro'.
Exam tip
Syngas is a building block: fuels (methanol, ethanol) and fertilizer (urea).
Sources
- Ministry of Coal — National Coal Gasification Mission
- NITI Aayog — Methanol Economy programme