Is Boron Trifluoride (BF₃) Polar or Nonpolar?

Is Boron Trifluoride (BF₃) polar or nonpolar?

BF₃ has three very polar B–F bonds (ΔEN = 1.94), but the trigonal planar geometry with 120° angles causes complete cancellation. No lone pair on boron to break the symmetry.

FormulaBF₃
PolarityNonpolar
Molecular GeometryTrigonal Planar
B–F BondΔEN = 1.94 (polar)
Net DipoleNo - dipoles cancel

Bond Dipoles

Each B–F bond has a huge ΔEN = 1.94 (F = 3.98, B = 2.04). These are among the most polar covalent bonds. Yet the molecule is nonpolar!

Molecular Shape & Dipole Cancellation

BF₃ is trigonal planar (120° angles). Unlike NF₃/NH₃ which are pyramidal, boron has no lone pair, so the geometry is flat and symmetric.

Net Dipole Moment

Three identical dipoles at 120° in a plane cancel exactly (like three equal forces pulling a ring at 120° angles - it doesn't move). Despite enormous bond dipoles, BF₃ is nonpolar.

See bond dipoles, partial charges, and net dipole moments on interactive 3D molecules.

Visualize Boron Trifluoride's Polarity in 3D

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