Question

Given below are two statements for catalytic properties of transition metals.
Statement I: First row transition metals which act as catalyst utilise their 3d electrons only for formation of bonds between reactant molecules and atoms on the surface of catalyst.
Statement II: There is increase in the concentration of reactants on the surface of catalyst which strengthens the bonds in reacting molecules.

• A. Both Statement I and Statement II are correct
• B. Both Statement I and Statement II are incorrect
• C. Statement I is correct but Statement II is incorrect
• D. Statement I is incorrect but Statement II is correct

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Transition metals are effective catalysts because they provide a surface for adsorption and can utilize both $3d$ and $4s$ electrons to form temporary bonds with reactants.
Step 2: Detailed Explanation:
Statement I: Catalytic activity involves both $3d$ and $4s$ electrons for bond formation with reactants. The use of the word "only" regarding $3d$ electrons makes this statement incorrect.
Statement II: According to the Adsorption Theory, while the concentration of reactants increases on the catalyst surface, the process actually weakens the bonds in the reacting molecules to lower the activation energy. Strengthening them would make the reaction harder to occur.
Step 3: Final Answer:
Both statements are scientifically incorrect.