Assertion (A): `Be(OH)_(2)` is soluble in `NaOH`.
Reason (R ): `Be(OH)_(2)` is amphoteric in nature.

Options

A. If both `(A)` and `(R )` are correct and `(R )` is the correct explanation of `(A)`.
B. If both `(A)` and `(R )` are correct, but `(R )` is not the correct explanation of `(A)`.
C. If `(A)` is correct, but `(R )` is incorrect.
D. If `(A)` is incrrect, but `(R )` is correct.

Answer

To analyze the given assertion and reason, we will break down the information step by step.

### Step 1: Understand the Assertion
The assertion states that beryllium hydroxide, \( \text{Be(OH)}_2 \), is soluble in sodium hydroxide (NaOH).

### Step 2: Chemical Reaction
To verify this assertion, we can look at the chemical reaction that occurs when beryllium hydroxide is treated with sodium hydroxide.
\[ \text{Be(OH)}_2 + 2 \text{NaOH} \rightarrow \text{Na}_2\text{BeO}_2 + 2 \text{H}_2\text{O} \]
This reaction shows that beryllium hydroxide reacts with sodium hydroxide to form sodium berylate, which is soluble in water.

### Step 3: Conclusion on Assertion
Since beryllium hydroxide does indeed react with sodium hydroxide to form a soluble compound, the assertion is **true**.

### Step 4: Understand the Reason
The reason states that beryllium hydroxide is amphoteric in nature.

### Step 5: Definition of Amphoteric
An amphoteric substance is one that can react with both acids and bases.

### Step 6: Verify Amphoteric Nature
Beryllium hydroxide can react with acids to form beryllium salts and with bases (as shown in the previous step) to form soluble berylate. This confirms that beryllium hydroxide is amphoteric.

### Step 7: Conclusion on Reason
Since beryllium hydroxide can react with both acids and bases, the reason is also **true**.

### Step 8: Relationship Between Assertion and Reason
The reason provided explains why the assertion is true. Since beryllium hydroxide is amphoteric, it can dissolve in sodium hydroxide.

### Final Conclusion
Both the assertion and reason are true, and the reason is the correct explanation for the assertion.

### Answer
The correct option for this question is **Option A**: Both Assertion and Reason are true, and the Reason is the correct explanation for the Assertion.

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