Questions: A Lewis structure for an isomer of C2H2F2 is shown below. Based on this structure, determine if the molecule is polar or nonpolar.

Solution Steps

The molecule has a planar structure with a central double bond. Each carbon atom is bonded to one hydrogen atom and one fluorine atom. This gives each carbon a trigonal planar geometry.

C-F bonds are polar due to the difference in electronegativity between carbon and fluorine. C-H bonds are considered essentially nonpolar.

Even though the individual C-F bonds are polar, their dipole moments are equal in magnitude and point in opposite directions (across the double bond). Therefore, they cancel each other out, resulting in no net dipole moment for the entire molecule.

Final Answer: The molecule is nonpolar.