Iron is a transition element in the fourth period. Iron forms compounds containing the ions $$\(\mathrm{Fe}^{2+}\)$$ and $$\(\mathrm{Fe}^{3+}\)$$.  When an excess of $$\(\mathrm{CN}^{-}(\mathrm{aq})\)$$ ions is added to green $$\(\left[\mathrm{Fe}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+}(\mathrm{aq})\)$$ ions, yellow $$\(\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4-}\)$$ complex ions are formed. Heating $$\(\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4-}\)$$ with dilute nitric acid and then neutralising the product with $$\(\mathrm{Na}_{2} \mathrm{CO}_{3}(\mathrm{aq})\)$$  produces red crystals, containing the $$\(\left[\mathrm{Fe}(\mathrm{CN})_{5} \mathrm{NO}\right]^{2-}\)$$ complex ion. $$\(\mathrm{NO}\)$$ is a neutral, monodentate ligand. Deduce the oxidation states of iron in: $$\( \left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4-} \ldots \ldots \ldots \ldots \ldots \ldots \ldots \ldots \ldots \ldots \ldots \ldots\left(\mathrm{Fe}(\mathrm{CN})_{5} \mathrm{NO}\right]^{2-}\ldots \ldots \ldots \ldots \ldots \ldots \ldots \ldots \ldots \ldots\ldots \)$$ 

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