Final answer:
Rainwater sticks to car windows because of the properties of cohesion, which allows development of surface tension forming droplets on surfaces, and adhesion, which is the attraction between water molecules and glass molecules.
Step-by-step explanation:
The property of water that causes drops to stick to windows of cars when it rains is predominantly cohesion and adhesion. Cohesion is the attraction between molecules of the same type which in this case, is water. This property allows for the development of surface tension, such that water forms droplets when placed on dry surfaces like a car window. On the other hand, adhesion is the attraction between water molecules and the molecules of other substances, like the glass on car windows. This property often manifests when the water molecules are more attracted to the car window than they are to each other, causing them to 'stick' to the window.
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