What is the difference in the EAN value of metal in the complexes sodium pentacynidonitrosyliumfer-rate (II) and pentaaquanitrosyliron (II) ion?

Options

A. 1
B. 2
C. Cannot be predicted
D. None of these

Answer

To find the difference in the Effective Atomic Number (EAN) values of the metal in the complexes sodium pentacyanidonitrosylium ferrate (II) and pentaaquanitrosyliron (II), we will follow these steps:

### Step 1: Identify the central metal and its oxidation state in both complexes.
- For sodium pentacyanidonitrosylium ferrate (II), the central metal is iron (Fe) with an oxidation state of +2.
- For pentaaquanitrosyliron (II), the central metal is also iron (Fe) with an oxidation state of +2.

### Step 2: Determine the atomic number of iron.
- The atomic number of iron (Fe) is 26.

### Step 3: Calculate the number of lone pair donating sites (ligands) for each complex.
- In sodium pentacyanidonitrosylium ferrate (II):
- There are 5 cyanide (CN⁻) ligands and 1 nitrosyl (NO) ligand.
- Total donating sites = 5 (from CN⁻) + 1 (from NO) = 6.

- In pentaaquanitrosyliron (II):
- There are 5 water (H₂O) ligands and 1 nitrosyl (NO) ligand.
- Total donating sites = 5 (from H₂O) + 1 (from NO) = 6.

### Step 4: Use the EAN formula to calculate the EAN for each complex.
The formula for EAN is:
\[ \text{EAN} = \text{Atomic Number} + \text{Oxidation State} + 2 \times \text{Number of Lone Pair Donating Sites} \]

- For sodium pentacyanidonitrosylium ferrate (II):
\[ \text{EAN} = 26 + 2 + 2 \times 6 = 26 + 2 + 12 = 40 \]

- For pentaaquanitrosyliron (II):
\[ \text{EAN} = 26 + 2 + 2 \times 6 = 26 + 2 + 12 = 40 \]

### Step 5: Calculate the difference in EAN values.
- Difference in EAN = EAN of sodium pentacyanidonitrosylium ferrate (II) - EAN of pentaaquanitrosyliron (II)
- Difference = 40 - 40 = 0

### Conclusion:
The difference in the EAN value of the metal in the complexes sodium pentacyanidonitrosylium ferrate (II) and pentaaquanitrosyliron (II) is **0**.

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