Recorded on March 5, 2012 using a Flip Cam. How To Tell if a Molecule Is Polar or Non-Polar? These are problems using 3D molecules run in the application Jmol to help you visualize the molecule to determine if it is polar or non-polar. Step 1: Draw the Lewis structure. Lesson 9: Molecular Polarity. Once we know its shape, we can determine whether a molecule is polar or nonpolar. A polar molecule is one in which one side, or end, of the molecule has a slight positive charge and the other side, or end, has a slight negative charge. Let's use 2 examples to clarify how to know if a molecule is polar. 1. H2O: First you look at the molecule. The molecule has 2 H’s and 1 O. Between H and O, oxygen is the more electronegative atom. How do we know? From the periodic table. The clos. Examining a diagram of the spatial arrangement of atoms that form a molecule can tell you if it is polar or non-polar. A molecule has polar bonds if there is a significant difference in electronegativity between the two elements. If the electronegativities of both elements are very similar or the same, the bonds are non-polar. We hope you will now know how to tell if a molecule is polar or non-polar. If you have any insights or questions, we would love to answer them for you! Share. Facebook Twitter Google+ LinkedIn StumbleUpon Tumblr Pinterest Reddit VKontakte Share via Email Print. Janice Powell. This video provides a fast way for you to determine if a molecule is polar or nonpolar. It provides examples so you can quickly distinguish nonpolar molecules from those that are polar. In such a molecule, the atoms from which the electron is pulled have a positive charge. Molecules bonded in such a way are called polar molecules, while those which don't have a charge are called non-polar. Determining if an atom is polar or non-polar requires understanding the bonds. EXAMPLE – Predicting Molecular Polarity: Decide whether the molecules represented by the following formulas are polar or nonpolar. (You may need to draw Lewis structures and geometric sketches to do so.) Polar Bonds and Molecular Shape. A polar molecule is a molecule that has a net dipole moment due to its having unsymmetrical polar bonds. There are two factors that go into determining if a molecule is polar or not.