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. 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.) Every sufficiently asymmetric molecule will be polar, but some more than others. The polarity of molecules is related to the polarity of bonds within the molecule, but just having polar bonds is not enough to create a polar molecule. 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. 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. Recorded on March 5, 2012 using a Flip Cam. 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. Chemistry. 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. Polar Bonds and Molecular ShapeA 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. In order to determine whether a molecule is polar or nonpolar, you must first examine its bonds. Does it have a polar covalent bond? Or ionic? What about lone pairs? Next, you have to examine the net partial charges. If there is a net partial charge, the molecule is polar. If not, it is nonpolar.