JEE Challenger
More from d and f Block Elements

Statements on Catalytic Properties of First Row Transition Metals

Given below are two statements for catalytic properties of transition metals.

Statement I : First row transition metals which act as catalyst utilise their 3d3\text{d} 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.

In the light of the above statements, choose the correct answer from the options given below :

Options

A

Both Statement I and Statement II are correct

B

Both Statement I and Statement II are incorrect

Correct
C

Statement I is correct but Statement II is incorrect

D

Statement I is incorrect but Statement II is correct

Topics & Concepts

Step-by-Step Solution

To determine the correctness of Statements I and II, we evaluate them based on the concepts of transition metal chemistry and heterogeneous catalysis:

  1. Analysis of Statement I:

    • According to the principles of transition metal chemistry, first-row transition metals use both their 3d3\text{d} and 4s4\text{s} electrons to form temporary bonds with reactant molecules at active surface sites during adsorption.
    • Since Statement I claims that these metals utilize their 3d3\text{d} electrons only, it is incorrect.
  2. Analysis of Statement II:

    • In heterogeneous catalysis (adsorption theory), the adsorption of reactant molecules onto the catalyst surface increases their concentration locally and weakens the chemical bonds within the reacting molecules. This weakening lowers the activation energy required for the reaction to proceed.
    • Since Statement II claims that the bonds in the reacting molecules are strengthened, it is incorrect.

Therefore, both Statement I and Statement II are incorrect.

Correct Option: B (Both Statement I and Statement II are incorrect)

Statements on Catalytic Properties of First Row Transition Metals | Chemistry PYQ Solution - JEE Challenger