List of top Chemistry Questions on Catalysis asked in BITSAT

Which feature of catalysts is illustrated by the following reactions?
(i) CO(g) + 2 H₂(g) → Cu/ZnO-Cr₂O₃ → CH₃OH(g)
(ii) CO(g) + H₂(g) → Cu → HCHO(g)
(iii) CO(g) + 3 H₂(g) → Ni → CH₄(g) + H₂O(g)