GATE 2026 Chemical Engineering, Q31 · Reaction Engineering
The correct answer is 1.4 to 1.6.
Question
Consider a homogeneous gas phase reaction, A + 2B → 2C + 3D, occurring at constant temperature and pressure in a varying volume batch reactor. The vessel is initially charged with 50 moles of A and 150 moles of B. The gases behave ideally. For complete conversion of A, the ratio of the final volume to the initial volume is ______ (rounded off to one decimal place).
Official answer: 1.4 to 1.6
Why
GATE 2026 official key: 1.4 to 1.6. Initial total = 200 mol. Complete A conversion consumes 100 mol B (50 mol B left), forms 100 mol C and 150 mol D. Final total = 50+100+150 = 300 mol. At constant T,P,
Explanation cross-checked for consistency. Final answer matches the official IIT answer key.