Which of the Following Molecules Has Polar Bonds but Is

Question

Which of the following molecules has polar bonds but is itself not polar?
A) NH3
B) CO2
C) CH4
D) H2O

Accepted Answer

All of the molecules have polar bonds because of differences in electronegativity between the atoms involved. However, for a molecule to be polar, the polar bonds must be arranged asymmetrically. In molecule A, there are no polar bonds. In molecule C, there is an asymmetric arrangement of polar bonds which makes the molecule polar. In molecule D, there is an asymmetric arrangement of polar bonds which makes the molecule polar. In molecule B, there is a polar bond between the carbon and oxygen atoms, but the molecule itself is linear, symmetrical, and nonpolar due to the arrangement of atoms.