Which of the following is amphoteric ?

Options

A. MgO
B. BeO
C. CO
D. `CO_(2)`

Answer

To determine which of the given options is amphoteric, we need to understand the definition of amphoteric substances and analyze the properties of the oxides mentioned.

### Step-by-Step Solution:

1. **Understand Amphoteric Substances**:
Amphoteric substances are those that can react with both acids and bases. This means they can either donate protons (H⁺) to bases or accept protons from acids.

2. **Identify Common Amphoteric Oxides**:
Common examples of amphoteric oxides include:
- Beryllium oxide (BeO)
- Aluminum oxide (Al₂O₃)
- Zinc oxide (ZnO)
These oxides can react with both acids and bases.

3. **Analyze the Given Options**:
- **MgO (Magnesium Oxide)**: This is primarily a basic oxide and does not exhibit amphoteric behavior.
- **BeO (Beryllium Oxide)**: This is an amphoteric oxide. It reacts with acids to form beryllium salts and with bases to form beryllates.
- **CO (Carbon Monoxide)**: This is a neutral oxide and does not react with acids or bases.
- **Al₂O₃ (Aluminum Oxide)**: This is also amphoteric, reacting with both acids and bases.

4. **Conclusion**:
Among the options, **Beryllium Oxide (BeO)** is amphoteric as it can react with both acids and bases.

### Final Answer:
**Beryllium Oxide (BeO) is amphoteric.**