Question

NiCl${}_2$ in the presence of dimethyl glyoxime (DMG) gives a complex which precipitates in the presence of NH${}_4$OH, giving a bright red color, Predict whether it is paramagnetic or diamagnetic.

• A. paramagnetic
• B. dimagnetic
• C. both
• D. none

Answer 1

Answer: (B)

dimagnetic

$NiC{l}_2$ in the presence of dimethyl glyoxime (DMG) gives a complex which precipitates in the presence of $N{H}_{4}OH$, giving a bright-red color.

The structure of the complex is shown in the figure.

The oxidation state of Ni in this compound is +2. The ligand is strong, so it causes pairing. Therefore, it shows $ds{p}^2$-hybridization.

The oxidation number of Ni is + 2. Atomic number = 28

$Ni=\left[Ar\right]3d^{8}4s^2$
$N{i}^{2+}=\left[Ar\right]3d^8$

$ds{p}^2$-Hybridization occurs.

There are no unpaired electrons, so the complex is diamagnetic.