Which of the following is an amphoteric hydroxide?
(a)`Mg(OH)_2`
(b)`Be(OH)_2`
(c)`Sr(OH)_2`
(d)`Ca(OH)_2`

Options

A. `Mg(OH)_2`
B. `Be(OH)_2`
C. `Sr(OH)_2`
D. `Ca(OH)_2`

Explanation

To determine which of the given hydroxides is amphoteric, we need to analyze each option based on their chemical properties.

### Step 1: Understand the term "amphoteric"
Amphoteric substances can react both as an acid and as a base. This means they can react with acids to form salts and water, and they can also react with bases to form complex ions or other products.

### Step 2: Analyze each option
1. **(a) Mg(OH)₂ (Magnesium hydroxide)**:
- Magnesium hydroxide is primarily basic. It does not show significant amphoteric behavior.

2. **(b) Be(OH)₂ (Beryllium hydroxide)**:
- Beryllium hydroxide is known to be amphoteric. It can react with acids to form beryllium salts and can also react with bases to form beryllate ions.

3. **(c) Sr(OH)₂ (Strontium hydroxide)**:
- Strontium hydroxide is also primarily basic and does not exhibit amphoteric properties.

4. **(d) Ca(OH)₂ (Calcium hydroxide)**:
- Calcium hydroxide is basic and does not show amphoteric behavior.

### Step 3: Conclusion
Based on the analysis, the only amphoteric hydroxide among the given options is **(b) Be(OH)₂ (Beryllium hydroxide)**.

### Final Answer:
**(b) Be(OH)₂**

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