Assertion: The ionic radii follows the order: `I^(-) lt I lt I^(+)`.
Reason: The smaller the value of `Z//e` the larger the size of the species.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If the 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 assertion is false but reason is true.

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 ionic radii follows the order: \( I^- < I < I^+ \). This means that the radius of the iodide ion (\( I^- \)) is smaller than that of neutral iodine (\( I \)), which is smaller than that of the iodide cation (\( I^+ \)).

1. **Understanding Ionic Radii**:
- Anions (negatively charged ions) are generally larger than their neutral atoms because they have gained electrons, which increases electron-electron repulsion.
- Cations (positively charged ions) are generally smaller than their neutral atoms because they have lost electrons, which decreases electron-electron repulsion and allows the remaining electrons to be pulled closer to the nucleus.

2. **Conclusion for Assertion**:
- The correct order of ionic radii should actually be \( I^- > I > I^+ \). Therefore, the assertion \( I^- < I < I^+ \) is incorrect.

### Step 2: Analyze the Reason
The reason states: "The smaller the value of \( Z/e \), the larger the size of the species." Here, \( Z \) represents the charge of the nucleus and \( e \) represents the charge of the electron.

1. **Understanding \( Z/e \)**:
- The ratio \( Z/e \) indicates the effective nuclear charge experienced by the electrons. A smaller \( Z/e \) value suggests that the electrons are less tightly held by the nucleus, leading to a larger ionic radius.
- In the context of ions, anions have a larger size due to the increased electron-electron repulsion, while cations have a smaller size due to the reduced electron-electron repulsion.

2. **Conclusion for Reason**:
- The statement about \( Z/e \) is correct. A smaller \( Z/e \) indeed corresponds to a larger ionic size.

### Final Conclusion
- The assertion is incorrect, while the reason is correct. However, since the assertion is incorrect, the reason cannot be used to justify the assertion.

### Summary of the Solution
- Assertion: \( I^- < I < I^+ \) is incorrect; the correct order is \( I^- > I > I^+ \).
- Reason: The statement about \( Z/e \) is correct.
- Therefore, the assertion is false, and the reason is true, but the reason does not support the assertion.