Question

Why is carbon dioxide a non-polar molecule, even though the C-O bonds are polar?

Answer 1

Polar and nonpolar molecule

• A polar molecule is formed when one end of the molecule has more positive charges than the other while the other end of the molecule contains more negative charges, forming an electrical pole.
• The non-polar molecules are those that do not have charges at the end because their electrons are evenly distributed throughout and those that symmetrically cancel one another.
• Examples of polar molecules are water and hydrochloric acid.
• Examples of nonpolar molecules are oxygen and methane.

Polarity of carbon dioxide

• The geometry of carbon dioxide $\left({\mathrm{CO}}_2\right)$ is linear.
• Structure of carbon dioxide:

• It has two polar bonds that are symmetrically arranged.
• Each oxygen atom creates a double bond with carbon.
• Since carbon $\left(\mathrm{C}\right)$ and oxygen $\left(\mathrm{O}\right)$ have different electronegativities, electrons aren't shared equally between them.
• There is no net molecule dipole moment since the two bond dipole moments cancel out.
• Thus, carbon dioxide is a non-polar gas.