# What is the charge of Mn in KMnO_4?

Oct 8, 2016

Well, the oxidation state of the metal centre is $+ V I I$.

#### Explanation:

But the charge on the permanganate ion is $- 1$. You have its potassium salt, i.e permanganate is the counterion to ${K}^{+}$, and thus it is reasonable that we have a $M n {O}_{4}^{-}$ ion. In other words, the charge on the OVERALL ION is $- 1$; it might lie on the metal or more likely the oxygen, but it is there.

When permanganate is reduced, it goes down to $M n \left(+ I I\right)$, a ${d}^{5}$ system that is almost colourless. This makes the redox couple very useful for titrations because chemical change can be observed macroscopically in real time by the dramatic colour change.

$M n {O}_{4}^{-} + 8 {H}^{+} + 5 {e}^{-} \rightarrow M {n}^{2 +} + 4 {H}_{2} O$

Is this balanced with respect to mass and charge? Don't trust my arithmetic.