Based on the VSEPR model, what is the polarity of CO2
The Correct Answer and Explanation is:
Carbon dioxide (CO2) is a nonpolar molecule based on the VSEPR (Valence Shell Electron Pair Repulsion) theory.
Explanation:
The central atom in CO2 is carbon (C), which is double-bonded to two oxygen atoms (O). To determine the polarity, we need to consider both the shape of the molecule and the distribution of electron density.
- Electron Pair Geometry:
CO2 has two bonding regions around the central carbon atom. The electron pairs are arranged in a linear geometry, with an angle of 180 degrees between the bonds. This arrangement minimizes the repulsion between electron pairs, making the geometry linear. - Symmetry:
The linear shape of CO2 means that the dipoles created by the individual bonds (each of which is polar due to the difference in electronegativity between carbon and oxygen) point in opposite directions. These dipoles cancel each other out because they are equal in magnitude but opposite in direction. - Bond Polarity:
The bond between carbon and oxygen is polar due to the difference in electronegativity between the two atoms. Oxygen is more electronegative than carbon, so the shared electrons are pulled closer to the oxygen atoms, creating partial negative charges on the oxygens and a partial positive charge on the carbon. - Molecular Polarity:
Despite the polar bonds, the linear molecular shape ensures that the dipoles are opposed to each other. As a result, they cancel each other out, leading to a nonpolar molecule overall.
Thus, CO2, despite having polar bonds, is nonpolar because of its linear symmetry, which causes the dipoles to cancel out.
