How can we polarize a molecule? — AD, Manaus City, Amazonia, Brazil
Some molecules, including water, are naturally polarized. This means that they have a positively charged end and a negatively charged end. But even normally non-polar molecules such as carbon dioxide can be polarized by exposing them to strong electric fields. Electric fields exert forces on electric charges and cause the electric charges in a molecule to rearrange—the positive charges in the molecule shift in one direction and the negative charges in that molecule shift in the other. As a result of this applied electric field, the molecule acquires a polar character—a negatively charged end and positively charge end. However, this polar character disappears as soon as the electric field is removed.