Question

Calculate the effective atomic number (EAN) of \( [Co(NH_3)_6]^{3+} \) ion.

Hint:

The EAN concept is crucial for predicting the stability of metal complexes. An EAN equal to 36 indicates a stable configuration, similar to that of a noble gas.

Answer 1

To calculate the Effective Atomic Number (EAN), use the following equation: \[ EAN = \text{Atomic number of the metal} - \text{Oxidation state} + 2 \times \text{Coordination number} \] Considering the complex \( [Co(NH_3)_6]^{3+} \): 
- The atomic number of cobalt is 27.
- The oxidation state of cobalt in the complex is +3.
- The coordination number, representing the number of ligands bound to cobalt, is 6.
Applying these values to the formula: \[ EAN = 27 - 3 + 2 \times 6 = 36 \]