Which of the following contains two amphoteric oxides?
A. sodium oxide, Zinc oxide , Magnesium oxide
B. Aluminium oxide, Calcium oxide, Zinc oxide
C. Potassium oxide, Lithium oxide, Carbon monoxide
D. Silver oxide, Lead oxide, Sodium oxide
E. Sulphur dioxide, Aluminium oxide, Carbon monoxide
Correct Answer: B
Explanation
The correct answer is B. Aluminium oxide, Calcium oxide, Zinc oxide.
Here's why:
- Amphoteric oxides are oxides that can react with both acids and bases to form salts and water.
- Aluminium oxide (Al₂O₃) is amphoteric because it reacts with both acids (like hydrochloric acid) and bases (like sodium hydroxide).
- Zinc oxide (ZnO) is also amphoteric. It can react with acids to form zinc salts and with bases to form zincates.
- Calcium oxide (CaO), however, is basic, not amphoteric. It reacts with acids to form calcium salts but does not react with bases.
Thus, option B contains two amphoteric oxides: Aluminium oxide and Zinc oxide.
The other options are incorrect because they contain oxides that are either basic or acidic, not amphoteric.
