Select the amphoteric substance in the following:

Options

A. `SO_(3)`
B. `NaOH`
C. `CO_(2)`
D. `Al(OH)_(3)`

Answer

To determine the amphoteric substance from the given options, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of Amphoteric Substances**:
- Amphoteric substances are those that can act as both acids and bases. They can react with acids to form salts and water, and they can also react with bases.

2. **Identify the Given Options**:
- The options provided include various compounds. For the purpose of this solution, let’s assume the options are:
1. SO3 (Sulfur Trioxide)
2. NaOH (Sodium Hydroxide)
3. CO2 (Carbon Dioxide)
4. Al(OH)3 (Aluminum Hydroxide)

3. **Analyze Each Option**:
- **SO3 (Sulfur Trioxide)**: This is a non-metal oxide and is known to be acidic. It does not exhibit basic properties.
- **NaOH (Sodium Hydroxide)**: This is a strong base (alkali) and does not exhibit acidic properties.
- **CO2 (Carbon Dioxide)**: This is also a non-metal oxide and is acidic in nature. It does not exhibit basic properties.
- **Al(OH)3 (Aluminum Hydroxide)**: This compound can react with both acids and bases. It can neutralize acids and also react with strong bases, making it amphoteric.

4. **Conclusion**:
- Among the given options, **Al(OH)3 (Aluminum Hydroxide)** is the only amphoteric substance because it can behave as both an acid and a base.

### Final Answer:
The amphoteric substance among the given options is **Al(OH)3 (Aluminum Hydroxide)**.

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