M&L Chapter 2.2 – PROPERTIES OF WATER
Pages 40 – 44
2.2
THE PROPERTIES OF WATER
1. Why is Earth called the “Blue Planet?
Name__________________________________ Pr ____
The Water Molecule
2. True or False. Water is one of the few compounds that is found in its liquid state on Earth.
3. Why is water a neutral molecule?
A. Polarity
4. When oxygen shares a pair of electrons with hydrogen, why are the electrons more likely to be
found near the oxygen nucleus than the hydrogen nucleus?
5. Oxygen is at one end of a water molecule. The two hydrogens are at the other.
Which end has a partial positive charge? _______________________________
Which end has a partial negative charge _______________________________
B. Hydrogen Bonding
6. Where do hydrogen bonds form?
7. What three atoms does hydrogen form a hydrogen bond?_______________________________
8. Which of the following is the weakest bond? Covalent, ionic, or hydrogen. (circle one)
9. “Because water is a polar molecule, it is able to form ______________________ hydrogen
bonds, which account for many of water’s special properties.”
10. Why is ice less dense than liquid water?
Cohesion
11. Define cohesion:
12. When water molecules are drawn together by hydrogen bonds, they can cause water to bead up
on a smooth surface. Their hydrogen bonds also allow them to form a network that small insects
can walk on, a property called ______________________________________.
Adhesion
13. Define adhesion.
14. What causes water to creep up the side of a graduated cylinder?
15. The ability of water to rise up into a narrow tube (without sucking on it!) is
called _________________________________.) Where do you see this in
living organisms? ___________________________________________.
16. On the diagram to the right, label where cohesion is occurring.
Label where adhesion is occurring.
Heat Capacity
17. Define heat capacity:
18. Why is water’s heat capacity so large?
19. Name one advantage to living things of water having such a high heat capacity.
Solutions and Suspensions
20. Define a mixture.
21. Give an example of a mixture.
A. Solutions
22. Describe what water molecules do when small amounts of ionic (or polar) substances are added
to them. See Figure 2-9 and the text.
23. Define solute. _______________________________________________________________
24. Define solvent _______________________________________________________________
25. What do we call a solution in which water has dissolved all the solute it can and can dissolve no
more? __________________________
B. Suspensions
26. Why is blood a suspension?
Acids, Bases, and pH
27. Write the chemical reaction for a water molecule splitting apart to form ions (we say that the
water molecule is “disassociating”).
28. What ratio of water molecules are dissociated at any one time? __________________________
29. Why is water neutral, even if it splits into charged ions?
30. What is the range of the pH scale? ______________________
31. What pH is neutral? ______ What is the pH range of acids (acidic solutions)? ______ of bases
(basic solutions)? ___________
32. Acids have more _____ ions than ____ions. Bases have more ____ ions than _____ ions.
A. Acids
33. Define an acid.
34. Where on the pH range would you find a strong acid? __________
B. Bases
35. Define a base.
36. Where on the pH range would you find strong bases? _________
C. Buffers
37. What is the pH range of most of the cells of the human body? ___________________
38. “Controlling pH is necessary for maintaining ___________________.”
39. Define “buffer.”
40. Name two blood buffers.
Read the “Chapter Mystery” on Page 33.
What is the question you are trying to answer?
Read the first clue on Page 37.
Where does the oxygen fish need come from? _______________________________________________
How are the two atoms of oxygen gas joined together? (what kind of bond?) ______________________
Read the second clue on page 42.
How does the temperature of Antarctic waters affect the amount of dissolved O2 available to ice fish?