Question

In $K_4\left[Fe\right(CN{)}_6]$, the EAN of Fe is

• A. 18
• B. 54
• C. 36
• D. 26

Answer 1

The correct option is C 36

EAN = Z – X + Y where Z is the atomic number of the central metal atom, X is the primary valance and Y is twice the secondary valency. Substituting the values here we get
EAN = 26 – 2 + 2(6)
EAN = 36
For verification, EAN will mostly be the atomic number of the next noble gas; here Kr which is 36.