How do transitional element compounds behave as catalysts?

Answer 1

In order to increase the rate of a reaction and to decrease the magnitude of the activation energy, compounds containing transitional elements or their oxides are used.

One of the fundamental behaviours of these metals are heterogenous catalysis. In this procedure, the 3d and 4s orbitals are usually free of electrons, and it allows to create bonds (with higher covalent character) with reactants, which will make the reactants to collide in the correct angle more efficiently.

Usage of these compounds in the reactions of gases is a special feature.

Given below a list of compounds used as catalysts and their usage.

1. Vanadium pentoxide or vanadium metal - To convert sulphur dioxide into sulphur trioxide in the manufacture of Sulphuric(VI) Acid.
2. Iron metal - Manufacture of ammonia by Haber's process
3. Chromium(III) Oxide or Zinc(II) Oxide - Manufacture of methanol using carbon monoxide
4. Titanium metal and compounds - To synthesize polymers out of alkenes (e.g. polythene).
5. Nickel metal - To saturate unsaturated hydrocarbons
6. Cobalt compounds - To synthesize carbonyl compounds

Answer 2

Transition metal compounds can act as catalysts by providing a surface for reacting molecules to bind to, lowering the activation energy required for the reaction to occur. The ability of transitional element compounds to undergo redox reactions and form multiple oxidation states makes them versatile as catalysts for a wide range of chemical reactions. Additionally, transitional element compounds can facilitate key steps in reaction mechanisms by providing sites for electron transfer or stabilizing reaction intermediates.