Which of the following species has the shortest bond length ?
`NO, NO^(+), NO^(2+),NO^(-)`

Explanation

To determine which of the given species (NO, NO⁺, NO²⁺, NO⁻) has the shortest bond length, we need to analyze the bond order of each species. The bond length is inversely proportional to the bond order: a higher bond order corresponds to a shorter bond length.

### Step-by-Step Solution:

1. **Identify the number of electrons in each species:**
- For NO: Nitrogen (N) has 7 electrons and Oxygen (O) has 8 electrons. Total = 7 + 8 = 15 electrons.
- For NO⁺: This species has lost one electron. Total = 15 - 1 = 14 electrons.
- For NO²⁺: This species has lost two electrons. Total = 15 - 2 = 13 electrons.
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