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Atomic Structure

What is a Carbon Dioxide Molecule?

Oxygen and carbon are both non-metals.
An oxygen atom has 6 electrons in its outer shell.
Oxygen is in group 6 of the periodic table.
A carbon atom has 4 electrons in its outer shell.
Carbon is in group 4 of the periodic table.

Two oxygen atoms and 1 carbon atom will each
share two electrons to form four covalent bonds
and make a carbon dioxide molecule  (CO₂).

This is a picture of a carbon dioxide molecule.

By sharing the four electrons where the shells touch each
oxygen and carbon atom can count 8 electrons in its outer shell.
These full outer shells with their shared electrons
are now stable, and the CO₂ molecule will
not react further with other oxygen or carbon atoms.

Each electron pair is one bond.
Carbon and oxygen have two bonds each between their atoms.
This is called a double bond.

The structural formula of a carbon dioxide molecule is written

There are no ions present (no + or - charges)
in carbon dioxide gas because the electrons are shared,
not transferred from one atom to another.
Carbon dioxide does form hydrogen ions
when it is dissolved in water (or rain water)
to become a weak acid called carbonic acid.

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