Test Index

MHTCET 18 Apr 2026 Shift 2 Paper

Question : 85 of 150

Marks: +1, -0

[\mathrm{Fe}(\mathrm{CN}) 6]^{3-}

Solution:

Concept:

EAN (Effective Atomic Number) is calculated for a metal ion using the formula:

EAN = Z - (\text{oxidation state}) + (\text{electrons donated by ligands})

Explanation:

[\mathrm{Fe}(\mathrm{CN})_6]^{3-}

, each

\mathrm{CN}^-

ligand has charge

-1

Let the oxidation state of Fe be

x

x + 6(-1) = -3

x - 6 = -3

, so

x = +3

Thus, the metal ion is

\mathrm{Fe}^{3+}

For Fe, atomic number

Z = 26

Each

\mathrm{CN}^-

ligand donates 2 electrons.

Total donated by

6

ligands

= 6 \times 2 = 12

electrons.

Now,

EAN = 26 - 3 + 12 = 35

Answer:

EAN = 35

Correct option: C. 35

Go to Question:

Prev Question

Next Question