An irreversible chemical reaction occurs on a porous catalyst. All the pores are of same size. In strong pore diffusion regime, the observed activation energy is 120 kJ mol⁻¹. The activation energy of diffusion is 10 kJ mol⁻¹. Assuming Arrhenius temperature dependency for both reaction and diffusion, which one of the following is the true activation energy (in kJ mol⁻¹) of the reaction?

Question

Accepted Answer

The correct answer is D, 230. GATE 2026 official key: (D). In the strong pore-diffusion regime, E_observed = (E_true + E_diffusion)/2, so E_true = 2(120) − 10 = 230 kJ/mol.