What are the precise oxidation states of the iron atoms located outside and inside the coordination — Practical Organic Chemistry and Purification Chemistry Question

💡 Solution & Explanation

The formula is $Fe_4[Fe(CN)_6]_3$. The iron outside the bracket is $Fe^{3+}$ (Iron-III), and the iron tightly bound to the cyanide ligands inside is $Fe^{2+}$ (Iron-II).