Consider the following species:
`N^(3-)`,`O^(2-)`,`F^(ө)`,`Na^(o+)`,`Mg^(2+)` and `Al^(3+)`
a. What is common in them?
b. Arrange them in the order of increasing ionic radii.

Explanation

To solve the problem step by step, let's break it down into parts:

### Step 1: Identify the Commonality
We need to determine what is common among the species given: `N^(3-)`, `O^(2-)`, `F^(1-)`, `Na^(1+)`, `Mg^(2+)`, and `Al^(3+)`.

1. **Determine the number of electrons for each species:**
- **N^(3-)**: Nitrogen has an atomic number of 7. Gaining 3 electrons gives it 10 electrons.
- **O^(2-)**: Oxygen has an atomic number of 8. Gaining 2 electrons gives it 10 electrons.
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