Which of the following are amphoteric ?

Options

A. `Be(OH)_(2)`
B. `Sr(OH)_(2)`
C. `Ca(OH)_(2)`
D. `Al(OH)_(3)`

Answer

To determine which of the given options are amphoteric, we need to understand the definition of amphoteric substances. Amphoteric substances are those that can act as both acids and bases. In the context of hydroxides, amphoteric hydroxides can react with both acids and bases.

**Step-by-Step Solution:**

1. **Understand the Definition of Amphoteric:**
- Amphoteric substances can react with both acids and bases. Hydroxides of certain metals exhibit this property.

2. **Identify Common Amphoteric Hydroxides:**
- Common amphoteric hydroxides include those of metals such as Aluminum (Al), Zinc (Zn), Lead (Pb), Beryllium (Be), and Tin (Sn).

3. **Analyze the Given Options:**
- The options provided are:
1. Beryllium (Be)
2. Strontium (Sr)
3. Calcium (Ca)
4. Aluminum (Al)

4. **Determine the Amphoteric Nature of Each Option:**
- **Beryllium (Be):** Its hydroxide (Be(OH)₂) is amphoteric.
- **Strontium (Sr):** Its hydroxide (Sr(OH)₂) is not amphoteric; it is basic.
- **Calcium (Ca):** Its hydroxide (Ca(OH)₂) is also not amphoteric; it is basic.
- **Aluminum (Al):** Its hydroxide (Al(OH)₃) is amphoteric.

5. **Conclusion:**
- The amphoteric substances from the options provided are Beryllium and Aluminum.

**Final Answer:**
- The amphoteric substances are Beryllium (Be) and Aluminum (Al).

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