Assertion : The radius of the first orbit of hydrogen atom is `0.529Å`
Reason : `NF_(3)`ionizes to give `F^(-1)` ions in aqueous solution.

Options

A. Assertion is correct, reason is correct, reason is a correct explanation for assertion.
B. Assertion is correct, reason is correct, reason is not a correct explanation for assertion
C. Assertion is correct, reason is incorrect
D. Assertion is incorrect, reason is correct.

Explanation

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

### Step 1: Analyze the Assertion
The assertion states that "The radius of the first orbit of hydrogen atom is 0.529 Å."

To verify this, we can use the formula for the radius of the nth orbit in a hydrogen atom:
\[ r_n = \frac{0.529 \, n^2}{Z} \, \text{Å} \]
Where:
- \( r_n \) is the radius of the nth orbit,
- \( n \) is the principal quantum number (1 for the first orbit),
- \( Z \) is the atomic number (1 for hydrogen).

For the first orbit (n=1, Z=1):
\[ r_1 = \frac{0.529 \times 1^2}{1} = 0.529 \, \text{Å} \]
Thus, the assertion is correct.

### Step 2: Analyze the Reason
The reason states that "NF3 ionizes to give F⁻ ions in aqueous solution."

To evaluate this statement, we need to consider the behavior of NF3 in water. NF3 (nitrogen trifluoride) is a stable molecule and does not readily ionize in aqueous solution. In fact, NF3 does not hydrolyze in water to produce fluoride ions (F⁻). Therefore, this reason is incorrect.

### Conclusion
Based on the analysis:
- The assertion is correct.
- The reason is incorrect.

Thus, the correct answer is that the assertion is true, but the reason is false.

### Final Answer
The correct option is: Assertion is correct and Reason is incorrect.

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