1. Structure & Properties of Water

2. STRUCTURE OF WATER H H O
1 molecule of water is made up of 2 hydrogen atoms bonded with 1 oxygen atom. The bond is covalent bond.

3. Hydrogen Bonds and Boiling Point
A hydrogen bond is a dipole-dipole force (one of kind INTERMOLECULAR FORCE) occurring when a hydrogen atom that is bonded to a highly electronegative atom (Fluorine, Nitrogen, Oxygen)
In general, compounds with hydrogen bonding have higher boiling points than comparable compounds.
Draw two H2O
Draw two H2S

4. Hydrogen Bonds and Density
Each water molecule forms multiple hydrogen bonds, so the intermolecular forces in water are strong.
When water forms ice, the ice crystals have large amounts of open space. Thus, ice has a low density.

5. POLAR MOLECULE
The positive hydrogen ends of 1 molecule are attracted to the negative end of the oxygen of another molecule. O H O H

6. CAPILLARY ACTION
The combined force of attraction among water molecules and with the molecules of the surrounding material.

7. SURFACE TENSION
The tightness across the surface of water that is caused by the polar molecules pulling on one another.
Makes the surface act like a solid

8. UNIVERSAL SOLVENT This is a nickname given to water.
Water dissolves LOTS of things.
Remember:
SOLVENT = the thing doing the dissolving
SOLUTE = the thing that dissolves away
Other polar molecules can be dissolved by water.
Why is water so good at dissolving things?
Because water is a polar molecule and is shaped like a wedge, it is able to break up substances into smaller pieces (dissolve).

9. COHESION – water stick to each other
Because water is a polar molecule, it is attracted to itself.
Cohesion – is the attractive force between water molecules. O H O H

10. COHESION Water molecules like to stick to each other.
Rubbing alcohol doesn’t like to stick to itself as much as water.

11. ADHESION – water like to stick to other substances
Because water is a polar molecule, it is attracted to other substances.
Adhesion – occurs when molecules of water are attracted to other substances.

12. Adhesion is going on between the windshield and the water droplet.