MCQ
The potassium ferrocyanide solution gives Prussian blue colour, when added to :
  • A
    $\mathrm{CoCl}_{3}$
  • B
    $\mathrm{FeCl}_{2}$
  • C
    $\mathrm{CoCl}_{2}$
  • $\mathrm{FeCl}_{3}$

Answer

Correct option: D.
$\mathrm{FeCl}_{3}$
d
$\left.\mathrm{FeCl}_{3}+\mathrm{K}_{4}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right] \rightarrow \mathrm{Fe}_{4}[\mathrm{Fe}(\mathrm{CN})]_{6}\right]_{3}$

$\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad$Prussian blue

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