Question

A pair of amphoteric oxides is

• A. Al₂O₃, Li₂O
• B. BeO, BO₃
• C. BeO, MgO
• D. BeO, ZnO

Answer 1

The Correct Option is D

Identifying Amphoteric Oxides

Amphoteric oxides are oxides that can react with both acids and bases to form salts and water. To identify the correct pair of amphoteric oxides from the given options, we need to consider the chemical properties of each oxide.

Options: 

1. Option A: \( \text{BeO} \), \( \text{MgO} \)
   While \( \text{BeO} \) (Beryllium oxide) is amphoteric, \( \text{MgO} \) (Magnesium oxide) is a basic oxide and does not react with bases.
2. Option B: \( \text{BeO} \), \( \text{ZnO} \)
   Both \( \text{BeO} \) (Beryllium oxide) and \( \text{ZnO} \) (Zinc oxide) are amphoteric oxides.
3. Option C: \( \text{Al}_2\text{O}_3 \), \( \text{Li}_2\text{O} \)
   \( \text{Al}_2\text{O}_3 \) (Aluminum oxide) is amphoteric, but \( \text{Li}_2\text{O} \) (Lithium oxide) is a basic oxide and does not react with bases.
4. Option D: \( \text{BeO} \), \( \text{B}_2\text{O}_3 \)
   \( \text{BeO} \) (Beryllium oxide) is amphoteric, but \( \text{B}_2\text{O}_3 \) (Boron trioxide) is an acidic oxide and does not react with acids.

Conclusion:

The correct answer is Option B: \( \text{BeO} \), \( \text{ZnO} \), as both are amphoteric oxides.

Answer 2

Amphoteric oxides are oxides that can react both as acids and as bases. Let's analyze the options:

- Option A (Al₂O₃, Li₂O): Al₂O₃ is an amphoteric oxide, but Li₂O is a basic oxide, not amphoteric.
- Option B (BeO, B₂O₃): BeO is amphoteric, but B₂O₃ is acidic, not amphoteric.
- Option C (BeO, MgO): BeO is amphoteric, but MgO is a basic oxide, not amphoteric.
- Option D (BeO, ZnO): Both BeO and ZnO are amphoteric oxides. BeO is amphoteric, and ZnO can react both as an acid and as a base.

Thus, the correct answer is:\({\text{(D) BeO, ZnO}}\)