Assertion : `Cu(OH))_(2)` is soluble in `NH_(4)OH` but not in `NaOH`.
Reason : `Cu(OH)_(2)` forms a soluble complex with `NH_(3)`.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false.

Answer

To solve the question, we need to analyze the assertion and the reason provided.

### Step 1: Analyze the Assertion
The assertion states that `Cu(OH)₂` is soluble in `NH₄OH` but not in `NaOH`.

- **Solubility in NH₄OH**: When `Cu(OH)₂` is treated with `NH₄OH`, it forms a soluble complex, specifically `[Cu(NH₃)₄]²⁺`, which is soluble in water. This indicates that `Cu(OH)₂` does dissolve in `NH₄OH`.

- **Insolubility in NaOH**: On the other hand, `Cu(OH)₂` does not form a soluble complex with `NaOH`. Therefore, it remains insoluble in `NaOH`.

**Conclusion for Assertion**: The assertion is true.

### Step 2: Analyze the Reason
The reason states that `Cu(OH)₂` forms a soluble complex with `NH₃`.

- **Formation of Complex**: When `Cu(OH)₂` reacts with `NH₄OH`, it indeed forms the complex `[Cu(NH₃)₄]²⁺`. This complex is soluble in the solution, confirming that `Cu(OH)₂` interacts with `NH₃` to form a soluble species.

**Conclusion for Reason**: The reason is also true and correctly explains why `Cu(OH)₂` is soluble in `NH₄OH`.

### Step 3: Final Conclusion
Both the assertion and the reason are true, and the reason is the correct explanation for the assertion.

### Answer:
Both assertion and reason are true, and the reason is the correct explanation for the assertion.

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