GATE 2025 Chemical Engineering, Q20 · Reaction Engineering
The correct answer is D, d(Micro-pore) < d(Meso-pore) < d(Macro-pore).
Question
Choose the CORRECT ordering of the diameter d of the different types of pores in a solid catalyst.
Official answer: d(Micro-pore) < d(Meso-pore) < d(Macro-pore)
Why
GATE 2025 official key: (D). By IUPAC convention, micropores (<2 nm) are smallest, followed by mesopores (2–50 nm), followed by macropores (>50 nm).
Explanation cross-checked for consistency. Final answer matches the official IIT answer key.