1. The Extraordinary Properties of Water

2. Water
A water molecule (H2O), is made up of _______ atoms one ___________and two ___________. H O 1

3. Water is Polar
In each water molecule, the _______________ attracts more than its "fair share" of ________________
The _____________ end “acts” __________
The ___________ end “acts” ____________
Causes the water to be _______________
However, Water is __________(equal number of e- and p+) --- Zero Net Charge

4. Hydrogen Bonds Exist Between Water Molecules
Formed between a highly ______________ atom of a polar molecule and a ________________
One hydrogen bond is ____________ , but many hydrogen bonds are _______________

5. Interaction Between Water Molecules
________ Oxygen end of one water molecule is attracted to the __________ Hydrogen end of another water molecule to form a HYDROGEN BOND

6. What are the Properties of Water?1

7. Properties of Water
At sea level, pure water boils at __________ and freezes at ________________.
The ___________________________________ ___________________________________ (lower atmospheric pressure).
For this reason, an egg will take longer to boil at higher altitudes 1

8. Properties of Water Cohesion Adhesion High __________ Heat
High Heat of _____________
________ Dense as a Solid 1

9. Cohesion
____________between particles of the same substance ( why water is attracted to itself)
Results in __________________________(a measure of the strength of water’s surface)
Produces a _____________ film on water that allows insects to walk on the surface of water 1

10. Helps insects walk across water
Cohesion …
Helps insects walk across water

11. Adhesion Attraction between two different substances.
Water will make ______________________ with other surfaces such as glass, soil, plant tissues, and cotton.
____________________-water molecules will “tow” each other along when in a thin glass tube.
Example: ___________________ process which plants and trees remove water from the soil, and paper towels soak up water. 1

12. Adhesion Causes Capillary Action
Which gives water the ability to “______________” structures

13. Adhesion Also Causes Water to …
Attach to a silken spider web
Form spheres & hold onto plant leaves

14. High Specific Heat
_________________ needed to raise or lower 1g of a substance 1° C.
Water _________________________________________, both for heating and cooling.
Water can absorb or release large amounts of heat energy with little change in actual temperature. 1

15. High Heat of Vaporization
Amount of energy to convert 1g or a substance from a _________________
In order for water to evaporate, _______________________________.
As water _____________, it removes a lot of heat with it. 1

16. Heat ______________ from the sun warmed surface of the earth is
___________________forms a kind of global ‘‘blanket” which helps to keep the Earth warm.
Heat ______________ from the sun warmed surface of the earth is
absorbed and held
by the vapor. 1

17. Water is Less Dense as a Solid
________________________ as a solid than as a liquid (ice floats)
Liquid water has _______________ that are constantly being ___________________________________________.
___________________ forms a _____________________ whereby molecules are set at fixed distances. 1

18. Water is Less Dense as a Solid
Which is ice and which is water? 1

19. Water is Less Dense as a Solid
Ice 1

20. Homeostasis a. Makes a ___________________
Ability to maintain a ______________________________ despite changing conditions
Water is important to this process because:
a. Makes a ___________________
b. Resists temperature change
c. _______________________
d. Coolant
e. Ice protects against temperature extremes (_________________frozen lakes) 4

21. Solutions & Suspensions
Water is usually part of a __________________.
There are two types of mixtures:
________________________

22. Solution Substance that is being dissolved
Ionic compounds disperse as ions in water
Evenly distributed
SOLUTE
Substance that is being dissolved
SOLVENT
Substance into which the solute dissolves

23. Solution

24. Suspensions
Substances that don’t dissolve but ____________ into tiny pieces.
Water keeps the pieces _________________ so they don’t settle out.

25. Acids, Bases and pH H2O  H+ + OH-
___________ water molecule in 550 million naturally dissociates into a Hydrogen Ion (H+) and a Hydroxide Ion (OH-)
Hydrogen Ion Hydroxide Ion
Acid Base
H2O  H+ + OH-

26. The pH Scale Indicates the ____________________
Ranges from ____________________
pH of _________________________
pH ______________________ … H+
pH ______________________… OH-
Each pH unit represents a factor of ______ change in concentration
pH 3 is 10 x 10 x 10 (1000) stronger than a pH of 6

27. Acids ________ ________ have a pH of ________
Produce lots of ______________

28. Bases _______________ have a pH of _______________
Contain _______________a nd fewer H+ ions

29. Buffers
Weak acids or bases that react with strong acids or bases to prevent sharp, sudden changes in pH (_________________________).
______________________________ to maintain homeostasis
Weak Acid
Weak Base