A first-order homogeneous liquid-phase reaction (A→B) occurs in a non-ideal isothermal reactor at steady state. The RTD variance from a pulse tracer experiment is 4 min². Feed flow rate is 5 L min⁻¹, reactor volume 25 L, and k = 0.4 min⁻¹. Based on the tanks-in-series model, the conversion (in %) is _______ (rounded off to one decimal place).

Question

Accepted Answer

The correct answer is 82 to 82.6. GATE 2026 official key: 82.0 to 82.6. τ = 25/5 = 5 min; N = τ²/σ² = 25/4 = 6.25. X = 1 − 1/(1+kτ/N)^N = 1 − 1/(1.32)^6.25 ≈ 82.4%.