Chemistry - Complete d-block Question with Solution | TestHub

When potassium permanganate (${\text{KMnO}}_4$) is heated at $513\text{ K}$, it decomposes to form potassium manganate, manganese dioxide, and oxygen gas.

$2{\text{KMnO}}_4\stackrel{513\text{ K}}{\to }{\text{K}}_2{\text{MnO}}_4+{\text{MnO}}_2+{\text{O}}_2$

The species ${\text{K}}_2{\text{MnO}}_4$ (potassium manganate) is green in color.

In ${\text{K}}_2{\text{MnO}}_4$, the oxidation state of $\text{Mn}$ is $+6$. The electronic configuration of ${\text{Mn}}^{6+}$ is $[\text{Ar}]3d^1$.

Since it contains one unpaired electron in the $d$-orbital, it is paramagnetic in nature.

Thus, the green paramagnetic species formed is ${\text{K}}_2{\text{MnO}}_4$.

Answer: ${\text{K}}_2{\text{MnO}}_4$