What is the maximum number of unpaired electrons in `Cu (Z = 29), Br^(-) (Z = 35)` and `K^+ (Z = 19)` ?

Explanation

To find the maximum number of unpaired electrons in Cu (Z = 29), Br⁻ (Z = 35), and K⁺ (Z = 19), we need to determine the electron configurations of each of these species and analyze their unpaired electrons.

### Step 1: Determine the electron configuration of Cu (Z = 29)
1. **Electron Configuration**: The electron configuration of Cu is:
- 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹ 3d¹⁰
2. **Identify Unpaired Electrons**:
- 4s has 1 electron (unpaired).
- 3d has 10 electrons (fully paired).
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