Out of `Co^(2+)` and `Ni^(2+)` ions, which has lower magnetic moment ?

Explanation

To determine which ion, Co²⁺ or Ni²⁺, has a lower magnetic moment, we need to follow these steps:

### Step 1: Determine the electronic configurations of Co²⁺ and Ni²⁺
- **Cobalt (Co)** has an atomic number of 27. Its electronic configuration is:
- Ground state: [Ar] 4s² 3d⁷
- For Co²⁺, we remove 2 electrons from the 4s orbital:
- Co²⁺: [Ar] 3d⁷ (2 electrons removed from 4s)

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