1. Structure & Properties of Water

2. STRUCTURE OF WATER
UNIVERSAL SOLVENT
DENSITY
COHESION
POLAR MOLECULE
SPECIFIC HEAT
ADHESION
CAPILLARY ACTION
SURFACE TENSION
BUOYANCY

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

4. The bond that forms water
STRUCTURE OF WATER H H O
The bond that forms water
is a covalent bond

5. CHEMICAL FORMULA
H2O = RIGHT
H2O = WRONG
2HO = WRONG

6. O H
1 molecule of water

7. A LOT OF MOLECULES OF WATERH O H O H O H O H O H O H O H O H
A LOT OF MOLECULES
OF WATER O H O H O H O H O H O H O H O H O H

8. Millions of molecules of water make up 1 raindrop

9. POLAR MOLECULE _ + A molecule that has electrically charged areas.
Also called a polar substance or polar compound. _ +
DURACELL

10. NON-POLAR SUBSTANCES Non-polar substances do not have charged ends
DURACELL

11. NON-POLAR SUBSTANCES Non-polar substances DO NOT dissolve in water.
Can you think of some examples of non-polar substances?
DURACELL

12. + + O H -

13. 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

14. POLAR MOLECULE THE PROPERTIES OF:
Cohesion, adhesion, specific heat, universal solvent, capillary action, surface tension
ALL HAPPEN BECAUSE WATER IS A POLAR SUBSTANCE!

15. SURFACE TENSION

16. SURFACE TENSION

17. SURFACE TENSION

18. 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

19. CAPILLARY ACTION
The combined force of attraction among water molecules and with the molecules of the surrounding material.
Cohesion + Adhesion

20. CAPILLARY ACTION

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

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

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

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

25. ADHESION

26. Water molecules like to stick to each other.
COHESION
Water molecules like to stick to each other.
ADHESION
Water molecules like to stick to other things.

27. Density of Water The density of water:
Prevents water from freezing from the bottom up.
Ice forms on the surface first—the freezing of the water releases heat to the water below creating insulation.
Makes transition between season less abrupt.

28. When water reaches 0oC, water becomes locked into a crystalline lattice with each molecule bonded to to the maximum of four partners.
As ice starts to melt, some of the hydrogen bonds break and some water molecules can slip closer together than they can while in the ice state.

29. SPECIFIC HEAT
Specific Heat = the amount of energy needed to increase the temperature of something 1 degree C.
Water has a really HIGH specific heat
That means it takes a lot of energy for water to increase its temperature.
This is because of the STRONG ATTRACTION between water molecules.
It’s POLAR!

30. SPECIFIC HEAT
WATER = 75°F
BEACH = 200°F

31. UNIVERSAL SOLVENT

32. 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.

33. Universal Solvent 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).