The rate expression for a heterogenous catalytic reaction is given by, - rᴀ = K.Kᴀ Pᴀ(1 + Kᴀ.Pᴀ + Kʀ.Pʀ), where K is surface reaction rate constant and Kᴀ and Kʀ are absorption equilibrium constants of A and R respectively. If Kʀ Pʀ >> (1 + Kᴀ Pᴀ), the apparent activation energy Eᴀ is equal to (given E is the activation energy for the reaction and ΔHʀ and ΔHᴀ are the activation energies of adsorption of R and A)

• A. E
• B. E + ΔHᴀ
• C. E + ΔHᴀ - ΔHʀ)
• D. ΔHᴀ + ΔHʀ