Fill in the blanks by choosing the appropriate word/words from those given in the brackets: (double salts, complex compounds, uni, bi, six, four, three, coordination, linkage, imperfect, perfect, normal, penetrating, central ion, chelating, Werner, Pauling)
In the complex ion,`[Fe("edta")]^(-)`, the C.N. and the O.N. of the central metal ion Fe are .......... and ......... respectively.

Explanation

To solve the question regarding the complex ion \([Fe(\text{edta})]^-\), we need to determine the coordination number (C.N.) and the oxidation number (O.N.) of the central metal ion, which is iron (Fe).

### Step-by-Step Solution:

1. **Identify the Ligand**: The ligand in the complex is EDTA (ethylenediaminetetraacetic acid). It is a hexadentate ligand, meaning it can donate six pairs of electrons to the central metal ion.

2. **Determine the Coordination Number (C.N.)**:
- Since EDTA can form six bonds with the central metal ion, the coordination number of Fe in this complex is 6.
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