How to Determine Polarity in Chemistry

The polar nature of water makes it a powerful solvent.
••• Photos.com/Photos.com/Getty Images

In chemistry, the concept of polarity refers to how some chemical bonds result in unequal sharing of electrons. This means shared electrons will be closer to one atom in a bond than another, which creates areas of positive and negative charge. You can use the difference in electronegativity of two atoms to predict whether they make polar, nonpolar or ionic bonds. Water is a well-known example of a polar molecule. According to the University of Arizona, "Water has a partial negative charge near the oxygen atom -- and partial positive charges near the hydrogen atoms."

    Draw the Lewis structure of the molecule. Note each element in the molecule.

    Look up each element in the molecule in an electronegativity table and note their electronegativity.

    Subtract the electronegativity of one atom in a bond from the other. Take the absolute value. A difference from 0.0 to 1.2 is nonpolar. A difference of 1.2 to 1.8 is polar. A difference of 1.8 and above is ionic.

    Repeat Step 3 for each bond in the molecule.

    Draw an arrow near each polar bond. Point the tip toward the more electronegative atom. If all the arrows point to a common center, the molecule is nonpolar. If they do not, the molecule is polar.

    Warnings

    • Some elements, such as fluorine, change electronegativity based on what elements they bond with.

Related Articles

How to Know If a Compound Is Polar or Non-Polar?
How to Explain Polarity
Molecular Activity of Water Vs. Oil
How to Calculate a Fraction Covalent
How to Find the Polarity of Compounds
How to Identify Molecules as Polar or Non-Polar
How to Determine if a Molecule Is Planar
Characteristics of Hydrogen Bonding
Definition of Molecular Bonds
How to Tell if a Molecule Is Bent
How to Figure Out the Ionic Percentage Once You Get...
Differences Between Polar & Nonpolar in Chemistry
The Differences in Covalent Crystals & Molecular Crystals
How to Determine If the Bond Between Two Atoms Is Polar?
How to Find the Number of Unshared Electrons
Why Do Compounds of Metals & Nonmetals Consist of Ions?
How to Calculate Polarity
How Do Van Der Waals Forces Hold Molecules Together?
How Do Polar Molecules Form Hydrogen Bonds?

Dont Go!

We Have More Great Sciencing Articles!