Potassium manganate `(K_(2)MnO_(4))` is formed when:

Potassium manganate (K_2MnO_4) is formed when

Potassium manganate (K_2MnO_4) is formed when

Potassium manganate (K_2MnO_4) is formed when

In the preparation of KMnO_(4) pyrolusite (MnO_(2)) is first converted to potassium manganate (K_(2)MnO_(4)) . In this conversion, the oxidation state off manganese changes from