Themes > Science > Chemistry > Inorganic Chemistry > Chemical Bonding > Bond Polarity

We've been talking a lot about Polarity so far. We can describe a molecule as polar if it has a center of positive charge in one or more particles, and a center of negative charge in the other one or more particles, thus causing it act much like the earth does with a north and south pole.This characteristic is also called a dipole moment.
Also, some polyatomic molecules exhibit polar behavior. They may have polar bonds but no dipole moment, when this occurs the individual bond polarities are arranged in such a way that all partial charges cancel out.  

In this example, the partial negative charge is on the central atom with two partial positive charges in the outer atoms. In this arrangement, the two positive charges are canceled out by the two negative charges so there is no overall net dipole moment.

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