Question

Transition metals and their compounds catalyses reactions because:

• A. they have completely filled $s-$subshell
• B. they have a comparable sizes due to poor shielding of $d-$subshell
• C. they introduce an entirely new reaction mechanism with a lower activation energy
• D. they have variable oxidation states which differs by two units

Answer 1

Answer: (C)

they introduce an entirely new reaction mechanism with a lower activation energy

The transition metals provide alternate reaction pathway which has lower activation energy . Hence, they act as a catalyst.