URGENT! plz help me T-T The compound MnO2 could either have a +4 or a +2 oxidation state on the manganese (Mn) atom. Explain how either scenario could occur.

See explanation

Explanation:

Manganese is a transition element. All transition elements have incompletely filled d orbitals which ultimately makes them to exhibit a variable oxidation state.

Manganese has electronic configuration of [Ar]4s23d5. This means that two electrons could be lost from the s orbital to yield Mn^2+. Also, two electrons could be lost from both s and d orbitals to yield Mn^4+

alkaline metals are lithium, sodium, rubidium, potassium, cesium and francium.

alkali metals have electronegativity from 0.7 to 1, lowest in periodic table of elements, which means that alkali metals (i group in periodic table) has positive oxidation number in compounds.

electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself.

alkaline metals (far left in main group) have lowest ionizations energy and easy remove valence electrons,

for example, potassium is the alkali metal and has a single valence electron in the outer electron shell.

electron configuration of potassium is: ₁₉k 1s²2s²2p⁶3s²3p⁶4s¹.

they can not exist alone in nature, because they are very reactive.