Give the oxidation state, d-orbital occupation and coordination number of the central metal ion in the following complexes: `(NH_4)-2 [CoF_4]`

Explanation

To solve the question regarding the complex \((NH_4)_2[CoF_4]\), we will determine the oxidation state, d-orbital occupation, and coordination number of the central metal ion (Cobalt).

### Step-by-Step Solution:

1. **Determine the Oxidation State of Cobalt (Co)**:
- The complex is \((NH_4)_2[CoF_4]\).
- Ammonium \((NH_4^+)\) has a charge of +1. Since there are 2 ammonium ions, their total contribution is \(2 \times +1 = +2\).
- Fluorine (F) has a charge of -1, and there are 4 fluorine atoms, contributing a total of \(4 \times -1 = -4\).
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