If oxygen in the air is O2 (since an oxygen atom has 6 electrons in the outer shell, it makes 2 double covalent bonds with another oxygen so that they’re both stable), why do oxygen molecules react with metals to form an oxide layer if O2 is stable? Its stable, so why react with anything?

Question

If oxygen in the air is O2 (since an oxygen atom has 6 electrons in the outer shell, it makes 2 double covalent bonds with another oxygen so that they’re both stable), why do oxygen molecules react with metals to form an oxide layer if O2 is stable? Its stable, so why react with anything?

In: Chemistry

Answer 1

Not all oxygen in the air exists as O2. The majority is O2; however, oxygen can also exist as ozone (O3), which can split into an O2 and a free oxygen radical (O·).

“Ozone is formed when heat and sunlight cause chemical reactions between oxides of nitrogen (NOX ) and Volatile Organic Compounds (VOC), which are also known as Hydrocarbons.” So basically nitrogen oxides & fuel sources react in sunlight to form ozone.

This means there are always free oxygen radicals in the atmosphere – these are responsible for most of the reactivity with oxygen.