On the surface of our water, there is a change of phase. We have air that is right above our surface. And what that means is these water molecules on the surface will have a limited number of hydrogen bonds because they cannot actually bond with the air molecules. They can only bond with the adjacent water molecules. And so if we take a look at this particular water molecule, we only have one, two, three of these hydrogen bonds. Now, whenever our water molecule moves or rotates from the surface, it will lose those hydrogen bonds.