Q1. [1]
Which of the following is an amphoteric oxide ?
- (A) Na₂O
- (B) K₂O
- (C) CO₂
- (D) Al₂O₃
Previously asked in CBSE board exam
2026 31/5/1 Q19
Generated by claude-sonnet-4-6 · 2026-06-15 06:45 · grounding rag
Model Answer
(D) Al₂O₃
Al₂O₃ (aluminium oxide) is an amphoteric oxide because it reacts with both acids and bases to form salt and water.
Explanation
- Na₂O and K₂O are basic oxides (formed from active metals); CO₂ is an acidic oxide (non-metallic).
- Amphoteric oxides show dual behaviour — they react with acids as well as bases. Al₂O₃ is the classic CBSE example of an amphoteric oxide.
- Remember: Zn, Al, Pb, Sn form amphoteric oxides — useful for MCQs.
If a question refers to an image, map, graph or diagram that is not shown here, open the Study Guide single page app, go to
Library and find the actual CBSE question paper. The original papers are also available on the CBSE website:
cbse.gov.in.