€¦  · Web viewSublimation—Snow or ice on Earth’s surface changes directly into water vapor in the atmosphere. Transpiration—Plants give off liquid water, most of which

Name: _________________________________ Period: ______ PART ONE: The Chemistry of LifeLesson 1: Unique Properties of Water…Read Lesson 1, pages 50-62 and explore all embedded links.

The glass in the picture above appears to be floating on water. How can a solid float on water? Actually, nothing is floating on the water; rather this picture depicts some of the most unique properties of water. What appears to be a glass floating on water is really water splashing upward in response to an item being dropped into the water.

INTRODUCTION 1. Can life exist without water? ______________

WATER, WATER EVERYWHERE 2. How much of the Earth is covered by water? ________________

3. What are the three states of water found in Earth? _____________________________________

Where Is All the Water? 4. Where is most of the water on Earth? __________________________________________

5. What percentage is underground? ________ in the air? ___________________ in bodies of

plants and animals? ________________________

6. How much of our surface water is salt water? ___________ freshwater? ____________

CHECKPOINT:Why is there a shortage of clean fresh water in many parts of the world?

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How Water Recycles 7. Fill in the blank rectangles on the diagram on the next page by labeling the following parts of the

water cycle: precipitation, sublimation, condensation, evaporation, transpiration, and runoff. The definitions below the Hydrologic (Water) Cycle diagram may help you to accomplish this task.

Evaporation—Liquid water on Earth’s surface changes into water vapor in the atmosphere. Sublimation—Snow or ice on Earth’s surface changes directly into water vapor in the

atmosphere. Transpiration—Plants give off liquid water, most of which evaporates into the atmosphere. Condensation—Water vapor in the atmosphere changes to liquid water droplets, forming

clouds or fog. Precipitation—Water droplets in clouds are pulled to Earth’s surface by gravity, forming

rain, snow, or other type of falling moisture. Runoff—Water flow that occurs when the soil is infiltrated to full capacity and excess water

from rain, meltwater, or other sources flows over the land.

8. Water cycles through both _______________ and _____________________ parts of the biosphere.

WATER MAY BE THE MOST IMPORTANT MOLECULE FOR LIFE 9. What makes water so important?

a. ________________________________________________________________________

b. ________________________________________________________________________

c. ________________________________________________________________________

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STRUCTURE AND PROPERTIES OF WATER Water is tasteless, odorless, and transparent and in small quantities colorless.

10. Why does water appear to be blue when seen in large quantities?

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11. Why is it important for water to be transparent?

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(1.) Polarity 12. What atoms make up water? ______________________________________________________

13. What is its chemical formula? _____________

14. Define polarity.

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15. Explain why water is a polar molecule.

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16. Explain how water molecules bond together.

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17. What type of bonds form between water molecules? ___________________________________

18. Name two other large molecules that use the same type of bonding as water molecules to hold

themselves together? ____________________________________________________________

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(2.) Solvency 19. Define homogeneous.

______________________________________________________________________________20. Explain how a solution is made, using the words: solution, solute, solvent, and homogeneous.

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21. Explain why water cannot dissolve oil.

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22. Water is the solvent in solutions called __________ and ___________.

Recall that an ion is an electrically charged atom or molecule. The dissociation of pure water into ions is represented by the chemical equation: 2 H2O → H3O+ + OH-

The products of this reaction are a hydronium ion (H3O+) and a hydroxide ion (OH-).

(3.) Cohesion 23. Why do water molecules tend to stick together in droplets rather than separating into individual

molecules? _____________________________________________________________________

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24. What happens when rain falls on a newly waxed car? ______________________________________________________________________________Why does this happen? ______________________________________________________________________________

(4.) Surface Tension 25. What property of water creates surface tension? ______________________26. What happens to water molecules on the surface or water that helps to create surface tension?

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27. Define surface tension.

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(5.) Adhesion 28. Explain what is meant by intermolecular forces bonding.

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29. What property allows water molecules to bond to another substance? _____________________

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(6.) Capillary action 30. Explain how capillary action works when you place a straw in a glass of water.

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31. What two forces allow capillary action to occur? What does it defy?

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32. Plants use capillary action to move water from the soil up into their roots. Explain a way

capillary action works in the human body.

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TEMPERATURE MODERATION[(7.)] Specific Heat

33. What do we mean when we say water has a high heat capacity?

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34. Energy must be _________________ to break hydrogen bonds, and energy is _______________ as heat when hydrogen bonds form.

35. What raises the temperature of water (NOT HEAT!!!)? ______________________________________________________________________________

36. What lowers the temperature of water?

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37. What do we mean when we say water has a high specific heat? ______________________________________________________________________________

38. What does specific heat measure? ______________________________________________________________________________

39. Does every substance on Earth have the same specific heat capacity? _____________________

40. What liquid substance on Earth has the highest specific heat capacity? _____________________

41. What does this property of water help to maintain in cells? ______________________________

42. Explain how human sweating and specific heat capacity of water work together to maintain

homeostasis.

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(8.) Note: Water has a high latent heat of vaporization which means a lot of energy is required to evaporate it. When it evaporates, water draws thermal energy out of the surface it’s on, which can be observed in sweating.

Freezing Point of Water 43. The freezing point of water (changing it from a liquid to a solid) is ___°C or ____°F.

44. Is water more dense or less dense in its solid form? _______________________________

Explain why this is possible.

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What types of bonds are responsible for this? _________________________

45. Why do other solid substances sink when placed in a liquid water?

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46. At what temperature is water the most dense? _______________

CHECKPOINT:Why do the bottoms of lakes, ponds, and other bodies of water remain unfrozen even when their surfaces are frozen? _____________________________________________________________________________________

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Boiling Point of Water 47. The boiling point of water (changing it from a liquid into a gas) is ___°C or ____°F.

48. Why do substances other than water tend to have a lower boiling point?

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WATER AND LIFE 49. How long can humans survive without food? _____________ without water? ___________50. Why is water so important in biological chemical reactions? (Relate your answer to

metabolic processes and water’s solvency ability; include anabolic and catabolic reactions in your answer.) ___________________________________________________________________________

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Anabolic reaction, represented by the chemical equation: 6 CO2 + 6 H2O + energy → C6H12O6 + 6 O2

Catabolic reaction, represented by the chemical equation: C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + energy

51. What two major fundamental metabolic reactions in organisms require water? ___________________________________________________________________________

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(9.) WATER ACTS LIKE A BUFFER 52. What does a buffer do?

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53. Why are buffer important to living organisms?

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54. How does water act as a buffer?

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Acids and Bases

55. What do acids release into a solution? ________________________________

56. What do bases release into a solution? ________________________________

57. Look at the pH scale pictured above and answer the following questions:a. Which substances is the most acidic? _______________________________________

b. Which substances is the least acidic? ________________________________________

c. Which substances is the most basic? ________________________________________

d. Which substances is the least basic? ________________________________________

e. How much more acidic is acid rain than urine? ________________________________

f. How much more basic is drain cleaner than soapy water? _______________________7

Acidity and pH 58. What does acidity refer to? ________________________________________________________

59. What is the pH of pure water? ___________ Is it acidic or basic? __________________________

Acids 60. How do acids taste? ___________________

61. What do they do to skin? __________________________________

62. Why doesn’t stomach acid eat through the lining of the stomach?

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63. What color does an acid turn blue litmus paper? ________________

Bases 64. How do bases taste? _______________

65. What do they feel like? ___________________________________

66. What can bases do to the skin? ____________________________

67. What color does a base turn red litmus paper? _________________

Neutralization 68. What happens when you mix an acid and a base?

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69. What do they from when mixed together? ___________________________________________

70. What do we call this type of reaction? _______________________________________________

(10.) Viscosity is a measure of a fluid's resistance to flow. It describes the internal friction of a moving fluid. A fluid with large viscosity resists motion because its molecular makeup gives it a lot of internal friction. A fluid with low viscosity flows easily because its molecular makeup results in very little friction when it is in motion.

CHECKPOINT:List the ten properties of water that we have covered, talked about in this lesson.(1). __________________________________________

(2.) __________________________________________

(3.)__________________________________________

(4.) __________________________________________

(5.) __________________________________________

(6.) __________________________________________

(7.) __________________________________________

(8.) __________________________________________

(9.) __________________________________________

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