For a heterogenous catalytic reaction, A + B → C, with equimole feed of A and B, the initial rate - rA0 is invariant with total pressure. The rate controlling step is

Surface Kc/(1 + TS) reaction between absorbed A and B in the gas phase

Surface reaction between absorbed A and absorbed B

Surface reaction between A in the gas phase and absorbed B

Desorption of C

✅ The correct answer is option D.

7769. For a heterogenous catalytic reaction, A + B → C, with equimole feed of A and B, the initial rate – rA0 is invariant with total pressure. The rate controlling step is