- Involves the use of catalysts.
- A catalyst is a substance that alters the rate of a chemical reaction but remains unchanged at the end of the reaction.
Types of Catalysis:
1. Homogeneous Catalysis
- Reactants, products, and catalysts are all in the same phase (solid, liquid, or gas).
2. Heterogeneous Catalysis
- Reactants, products, and catalysts are in different phases.
Characteristics of Catalysts
1. Catalysts alter the rate of chemical reactions.
2. Catalysts themselves are not consumed during the reaction, though their appearance (colour/texture) may change.
3. Catalysts do not initiate reactions; they only act on reactions already in progress.
4. Catalysts are specific in action; each catalyst is specialised for certain reactions (though some inorganic catalysts are multipurpose).
5. Catalysts have no effect on equilibrium in reversible reactions.
6. Catalysts cannot change the type of products formed, only the quantity formed per time.
7. Even a small quantity of a catalyst can significantly alter a reaction.
8. The strength of a solid catalyst can be increased by increasing its surface area (e.g., grinding into powder).
9. In chemical equations, catalysts are written above the reaction arrow, since they do not affect the overall stoichiometry.
No comments:
Post a Comment