An amphoteric oxide is a metallic oxide that can react with both acids AND bases to form salt and water. The word comes from Greek amphoteros meaning 'both'.
Definition: Reacts with both acids and bases.
Key Examples: Al₂O₃ (Aluminium oxide), ZnO (Zinc oxide).
Most Important for CBSE: Al₂O₃ and ZnO.
Non-metal oxides are usually acidic; metal oxides are usually basic.
The most important amphoteric oxides:
| Oxide Type | Reacts With | Example |
|---|---|---|
| Acidic Oxide | Only bases | CO₂, SO₂ |
| Basic Oxide | Only acids | CaO, MgO |
| Amphoteric Oxide | Both acids AND bases | Al₂O₃, ZnO |
Amphoteric oxides react with both acids and bases. Examples: Aluminium oxide (Al₂O₃) and Zinc oxide (ZnO).
Water (H₂O) is often considered amphoteric in behaviour but technically it is not a metallic oxide. The classic amphoteric oxides are Al₂O₃ and ZnO.
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