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Atomic Structure

What is an Oxygen Molecule?

Oxygen is a non-metal.
An oxygen atom has 6 electrons in its outer shell.
Oxygen is in group 6 of the periodic table.
Two oxygen atoms will each share two electrons to form
two covalent bonds and make an oxygen molecule  (O₂).

This is a picture of an oxygen molecule.

By sharing the four electrons where the shells touch
each oxygen atom can count 8 electrons in its outer shell.
These full outer shells with their shared electrons
are now stable, and the O₂ molecule will
not (normally) react further with other oxygen atoms.

Note the 2 pairs (4 electrons) shared between the atoms.
Each electron pair is one bond.
Oxygen has two bonds between its atoms.
This is called a double bond.

The structural formula of an oxygen molecule is written

There are no ions present (no + or - charges) in oxygen gas
because the electrons are shared,
not transferred from one atom to another.

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