Given below are two statements :
Statement (I) : Dimethyl glyoxime forms a six membered covalent chelate when treated with ${NiCl}_{2}$ solution in presence of ${NH}_{4} OH .$
Statement (II) : Prussian blue precipitate contains iron both in $(+ 2)$ and $(+ 3)$ oxidation states.

Question

In the light of the above statements, choose the most appropriate answer from the options given below:

TestHub · Accepted Answer

According to Statement I,

On addition of dimethylglyoxime (DMG) to nickel ion solution and on adding little bit of ammonia to make solution basic, it will give a red precipitate. This is a very specific test for nickel $+ 2$ cation.

The reaction is as follows,

${Ni}^{2 +} + {NH}_{4} OH + dmg \to$

$2$ hydrogen bonded chelatesare formed.

According to Statement II,

$\begin{matrix} III \\ {Fe}_{4} \end{matrix}$ $\begin{matrix} II \\ {[Fe {(CN)}_{6}]}_{3} \end{matrix}$

Prussian Blue

IN this complex Fe is at $+ 3 as well as + 2$ oxidation state. Where ionisation sphere is ${Fe}^{3 +}$ and coordination sphere has ${Fe}^{2 +}$

Hence option A is the answer..

Chemistry - Coordination Chemistry Question with Solution | TestHub

Options:

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