Is #CO_2# an ionic salt or covalent molecule?

1 Answer
Jan 10, 2017

A non-polar covalent molecule (with a polar covalent bond).

Explanation:

#CO_"2"# is made up of:
- 1 carbon atom,
- 2 oxygen atom.

Carbon and oxygen are non-metals, thus we know carbon dioxide is a covalent compound.


Another method is by calculating the difference in electronegativity, we can determine the polarity of the molecule. Calculating the electronegativity also provides the intramolecular force within the compound.

Ionic compounds
- Ionic: #1.7+#

Covalent compounds
- Polar Covalent Bonds: #0.5->1.6#
- Non-polar Covalent Bonds: #0.0->0.4#

#DeltaEN= 3.5 - 2.5#
#=1.0#

#1# is between #0.5->1.7#, therefore, there is a polar covalent bond within the molecule. In addition, the molecule is a covalent compound.

#CO_"2"# is a polar covalent molecule... under normal circumstances.

Examining the geometric shape of the molecule, results in the linear shape - a symmetrical geometry. This results in the dipoles cancelling out, therefore the molecule becomes non-polar, despite its polar bond.

Therefore, #CO_"2"# is a covalent molecule, non-polar specifically, however, it has a polar covalent bond (intramolecular force).

Hope this helps :)