TG EAMCET 2 May 2025 Shift 2 Paper

First, when the sodium fusion extract reacts with iron(II) sulfate, a chemical reaction happens that forms a compound called sodium ferrocyanide.
6NaCN+FeSO4→Na4[Fe(CN)6]+Na2SO4
Next, when you add concentrated H2SO4, the iron(II) changes to iron(III). This iron(III) reacts with sodium ferrocyanide to make a blue colored compound called Prussian blue.
3Na4[Fe(CN)6]+4Fe3+

xH2O

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Fe4[Fe(CN)6]3⋅xH2O
The blue color (Prussian blue) shows that nitrogen is present in the organic compound.