Arrange the following species in decreasing order of bond angle.
`NO_2^+ , NO_2 , NO_2^-`

Explanation

To arrange the species \( NO_2^+ \), \( NO_2 \), and \( NO_2^- \) in decreasing order of bond angle, we will analyze each species based on their molecular geometry and hybridization.

### Step-by-Step Solution:

1. **Analyze \( NO_2^+ \)**:
- **Valence Electrons**: Nitrogen has 5 valence electrons, and each oxygen has 6 valence electrons. The positive charge means we lose one electron, giving us a total of \( 5 + 2 \times 6 - 1 = 16 \) electrons.
- **Bonding**: Nitrogen forms two double bonds with the two oxygen atoms. Each double bond counts as one bond pair.
- **Lone Pairs**: There are no lone pairs on the nitrogen atom.
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