Chapter 2, Lesson 2 Multimedia
Evaporation
What's this?Learn more →
- Heating the water on the paper towel increases the motion of the water molecules.
- When the molecules have enough energy, they can move fast enough to break away from the attractions holding them to other molecules.
Heating and Evaporation
Compare the number of motion lines and the spacing of the water molecules in the water on each paper towel. Heated water molecules have more energy and move faster than the room temperature water molecules. These faster moving molecules are able to overcome the attractions they have for other water molecules more easily and evaporate.
Models of Water Molecules
- The ball-and-stick model shows that atoms are bonded at certain angles in the molecule.
- The space-filling model shows the region taken up by the electron clouds of the atoms in the molecule.
Liquid Water
The molecules in liquid water are attracted to one another but are able to slide past each other. If you look closely, you can see some molecules where the hydrogen atoms of one molecule are “bonded” to the oxygen of another.
This video appears courtesy of Roy Tasker.
© Roy Tasker, VisChem Project.
Water Vapor
- Molecules are very far apart. After evaporating, the molecules of water vapor has separated from the molecules in the liquid water.
- The molecule itself does not break apart into individual atoms.
This video appears courtesy of Roy Tasker.
© Roy Tasker, VisChem Project.
