Final answer:
Carbon dioxide is non-polar because its linear molecular geometry causes the dipoles from the polar C-O bonds to cancel out, resulting in no net dipole moment for the molecule.
Step-by-step explanation:
Carbon dioxide (CO₂) is considered a non-polar molecule even though it contains polar C-O bonds. The molecular geometry of CO₂ plays a crucial role in its overall polarity. As CO₂ is a linear molecule, the two polar bonds are placed directly opposite each other, leading the dipoles to have the same magnitude but opposite directions. This symmetrical arrangement causes the individual polarities to cancel out, resulting in no net dipole moment for the molecule, thereby making carbon dioxide non-polar.
The Lewis structure and Valence Shell Electron Pair Repulsion (VSEPR) theory reveal that the molecule's linear shape is due to the arrangement of the electron pairs around the central carbon atom. In contrast to water (H₂O), which has a bent structure due to the presence of lone electron pairs and does not allow the dipoles to cancel out, leading to a polar molecule. This illustrates why, despite having polar bonds, the linear shape of CO₂ causes it to be non-polar.