Polar molecules

[Steven Garcia 1H]

If a molecule has a lone pair, can we predict that it will be a polar molecule? Or is this not always the case?

[Aili Ye 4L]

Often, the lone pair can distort the symmetry and will create a polar molecule, but it is not always the case.

[Isabelle_Maletz_3E]

In most cases a lone pair will cause the entire molecule to be polar. However, if there are enough bonded atoms around the central atom, the polarity will decrease as the surrounding elements make up for the distortion caused by the lone pair.

[Hedi Zappacosta 1E]

A good example of this is water. Without the lone pair on the Oxygen atom, the molecule would be nonpolar. However, the extra electrons give the molecule a bent shape, making it polar.