Intermolecular Forces

Oily and greasy substances are usually nonpolar. In theory, one way to get grease off your hands after working on your bike or car is to rub your hands with some greasy potato chips afterwards. However, this would probably create more of a mess!

Why do some substances exist as solids at room temperature, and others might be liquids or gases? How is it possible for nonpolar substances to stick together as solids or liquids? With the case of polar objects, the oppositely charged ends are attracted to each other. Nonpolar objects are attracted to each other when electrons are gathered one side of the molecule. This is known as the London dispersion force. What does all of this mean? It means that polar substances dissolve in polar solvents and nonpolar substances dissolve in nonpolar solvents. Since chemists have figured this out, you will not have to clean your hands with potato chips.