1. Properties of Water
Practice Quiz

2. 1. What two elements make up water?
Hydrogen (H) & Oxygen (O)
2. Write the chemical formula for water.
H2O
3. Is water an element, compound,
or mixture?
Compound

3. 4. Define the term compound.
A substance with two or more elements chemically combined in definite proportions.
5. What kind of chemical bond exists
between a hydrogen and oxygen
atom in a water molecule?
A covalent bond

4. 6. Draw a model of a water molecule.
(+)
(-)
The parentheses mean ‘partial.’
7. Draw partial (+) and partial (-) charges on
the water molecule you drew above.
δ +
This symbol also means partial →

5. 8. Which of the following molecules are polar?
(-)
(+)
(-)
(-)
(-)
(+)
(+)
(-)
(-)
(+)
(+)
water
carbon dioxide
ammonia
(+)
(+)
(-)
(+)
(-)
(-)
(-)
(+)
(+)
(+)
(+)
Hydrogen chloride
formaldehyde
methane

6. 9. Draw two water molecules and a hydrogen bond.
(+)
(-) 1
The use of dashed lines show that hydrogen bonds are relatively weak.
Hydrogen bond 4 3 2
10. How many hydrogen bonds can a water
molecule form with other water molecules?
Four

7. 11. What term describes the attraction between molecules of the same substance?
Cohesion B A No
12. Without a hydrogen bond, when molecule A
moves to the right, will it be able to drag
molecule B along with it?

8. Yes 13. With a hydrogen bond between them, will
molecule A be able to drag molecule B along
with it? A B
Yes

9. 14. What are some examples of water cohesion?
Surface tension
Drops on a penny
Insect trapped in water
A proboscis keeps this bee at a safe distance

10. 15. What are some examples where surface tension breaks down?
“Scaring” pepper
Bread clip motor boat

11. 16. What term describes the attraction between molecules of different substances?
Adhesion
(+)
(-)
glass
Water drop on glass slide

12. 17. What will happen when a charged rod or balloon is brought up close to a stream of water?
The water will be attracted toward the rod

13. A meniscus that water forms in a glass tube.
18. What are some examples of water adhesion?
A meniscus that water forms in a glass tube.
Capillary action

14. Duck feathers repel water
19. What are some examples of anti-adhesion?
Scotchgard ® carpet
Water on wax paper
Wax-layer on leaves
Duck feathers repel water

15. Nature has never made this type of material.
New: Researchers have made an omniphobic material that repels both water and oil.
Nature has never made this type of material.

16. Heat Capacity 20. What is the term which describes the amount of heat
energy needed to increase a substance’s temperature?
Heat Capacity

17. Water 21. Which substance in the chart is able to absorb the
most heat for a given change in temperature?
Water

18. Air 22. Which substance in the chart is able to absorb the
least amount of heat for a given change in temperature?
Air

19. 23. What example in the Properties of Water lab
demonstrated a low heat capacity for air and a
high heat capacity for water?
Air-filled balloon
Water-filled balloon

20. 25. What are some examples of mixtures?
24. What is a mixture?
A substance made up of elements or compounds that are combined but not chemically bonded together.
25. What are some examples of mixtures?
copper
zinc
water
sugar
corn syrup
CO2
caramel
caffeine
citric acid
Beef
Onion
Tomato
Lettuce
Cheese
Ketchup
Mustard
bread

21. what does the dissolving what is being dissolved
26. What are two kinds of mixtures made with water?
Solutions and suspensions
27. Compare solvent, solute, and solution.
water
solvent
what does the dissolving
Sugar water
solution
Sugar cubes
solute
what is being dissolved

22. 29. Which substance(s) below dissolve in water?
28. Define a solution?
A mixture in which the molecules of the mixed substances are evenly spread out.
29. Which substance(s) below dissolve in water?
Magnesium sulfate
polar
iodine
Non polar
salt
polar
Non polar
paraffin wax
oil
Non polar

25. 31. What some examples of suspensions?
30. What is a suspension?
A mixture from which some of the nondissolved particles settle out slowly upon standing.
31. What some examples of suspensions?
Chocolate milk
Paint
Blood

27. When water breaks apart, what kind of ions are formed?
Hydrogen (H+) ions and hydroxide (OH-) ions
( ) +
(-)
33. What does the pH scale indicate?
It indicates the concentration of hydrogen ions (H+) in a solution.

28. 34. What is the range of the pH scale?
0 to 14
What is the pH of a substance that has an
equal number of H+ and OH- ions? 7
Substances with a pH below 7 are ________
while those above 7 are _________?
Acids
Bases

29. 37. Acids have more ____ions than _____ ions?
OH-
38. The _______the pH, the greater the acidity.
lower
39. _______ have more OH- ions than H+ ions?
Bases

30. Place the 5 substances listed below on the scale to the right.
Oven cleaner
Lemon juice
Pure water
Human blood
Soap
Lemon juice
Oven cleaner
Human blood
Soap
Pure water
Click for answer

31. The pH in most cells in the human body must
stay between _______ and______ ?
6.5
7.5
__________ are weak acids or bases that can
react with strong acids or bases to stop sharp,
sudden changes in pH.
Buffers
43. Buffers play an important role in the process of
______________, where living things are able
to maintain a stable, internal environment.
homeostasis