Q. 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
Correct Answer: (c) All the three
UPSC Prelims 2025 GS Paper's Solution
Explanation :
Coal gasification
Coal gasification produces a synthesis gas (syngas) mixture of CO and H₂, which serves as a versatile building-block for many downstream chemicals:
Ethanol
– Syngas → (Fischer–Tropsch or direct catalytic) → ethanol
– Or via syngas fermentation by specialized microbes
Nitroglycerine
– Syngas → NH₃ (Haber–Bosch) → HNO₃ (Ostwald process)
– HNO₃ + glycerol → nitroglycerine (nitration)
Urea
– Syngas → NH₃
– Syngas also supplies CO₂
– NH₃ + CO₂ → ammonium carbamate → urea
Since all three—ethanol, nitroglycerine (via HNO₃ from NH₃), and urea—can be derived ultimately from coal-derived syngas, the correct answer is (c) all three.
