Question

Find the oxidation number of $$Mn$$ in $$KMnO_4$$ (oxidation number of $$K$$ is $$+1$$, oxidation number of $$O$$ is $$-2$$)

Answer 1

Oxidation state of potassium $$= + 1 $$

Oxidation state of oxygen $$ = -2$$

Let the oxidation state of $$Mn$$ be $$x$$

$$ 1 \times (+1) + x + 4(-2) = 0 $$

$$ (+1) + x + (-8) = 0 $$

$$ x - 7 = 0 $$

$$ x = +7$$