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Rohinb97
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Are these reactions for formation of brown ring complex correct?

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The above are the reactions given in my book for the qualitative analysis of nitrate ion (formation of the brown ring complex). I think that the reactions above are incorrect. The first one shows formation of $Fe^{3+}$ , which should be attacked by excess of $H_2O$ to give ferrum hexaaqua (III) sulphate, not ferrum hexaaqua (II) sulphate. Now that should be attacked by $NO$ as a ligand and give $[Fe(H_2O)_6NO]SO_4$, where O.N. of $Fe$ being 3+.

Here the reactions show that the $Fe$ already present gives $[Fe(H_2O)_6]^{2+}$ and then $NO$ acts as a neutral ligand to form the complex. But by the reactions shown in the book, even after formation of the brown ring complex $Fe^{3+}$ is still present in the solution....which according to me shouldn't be.

I need some clarity on this.

Rohinb97
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