Arrange `I^(-), I and I^(+)` in the decreasing order of their atomic radius

Explanation

To arrange the ions \( I^{-}, I, \) and \( I^{+} \) in decreasing order of their atomic radius, we need to consider the effect of charge on the size of the ions and the neutral atom.

### Step-by-Step Solution:

1. **Understanding Atomic and Ionic Radius**:
- The atomic radius refers to the size of a neutral atom, while the ionic radius refers to the size of an ion (either positively or negatively charged).
- Anions (negatively charged ions) are generally larger than their neutral atoms because they have gained electrons, which increases electron-electron repulsion and expands the electron cloud.
- Cations (positively charged ions) are smaller than their neutral atoms because they have lost electrons, reducing electron-electron repulsion and allowing the remaining electrons to be pulled closer to the nucleus.
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