Unique Properties of Water

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Unique Properties of Water

• Mrs. McAven
• 8th Grade Science
• Riverwood Middle School

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The Properties of Water

• CH.2 section 1
• Read pgs. 46-51
• On page 51 answer s 1-3 (ALL) in complete
  sentences.
• CH. 2 section 2
• Read pgs. 52-57
• On page 57 answer s 1-2 (ALL) in complete
  sentences.

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Properties of Water

• What are some characteristics that make you
  different from everybody else? Maybe you can play
  basketball really well, or have a freckle on the
  tip of your elbow, or maybe you can draw better
  than anybody else you know.
• It may seem strange, but each substance in the
  world has special characteristics that make it
  different from every other substance. Just like
  you, they have characteristics, or properties,
  that make them unique. Believe it or not, water
  has some of the most unique properties of all!

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VOGO

• Side 1
• WORD
• Definition

• Side 2
• Example/Sentence
• Picture

Where can I find these words? Chapter 2 (pg. 44)
Words Adhesion Buoyancy Capillary
Action Cohesion
Density Polarity Specific Heat Surface
Tension Universal Solvent
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ADHESION

• Definition
• the ability of water molecules to attract to
  other substances.
• Because water molecules are polar (having one
  positive end and one negative end) they attract
  other substances.
• Example
• raindrops sticking to a window or glass
• water sticking to paper towel

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BUOYANCY

• Definition
• the ability of an object to float in water.
• Example
• floating in the ocean or a pool
• a boat

7
CAPILLARY ACTION

• Definition
• the process that moves water through a narrow
  porous space
• Example
• water moving up a straw
• water moving up a plant stem

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COHESION

• Definition
• the ability of water molecules to attract
  towards each other.
• Because water molecules are polar (having one
  positive end and one negative end), they attract
  each other.
• Example
• water dome
• rain drops

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DENSITY

• Definition
• the measure of mass of a substance per unit
  volume
• Example
• ice floating on water

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POLARITY

• Definition
• when one molecule has opposite charges on each of
  its ends (one end is slightly positive, the other
  end is slightly negative).
• Example
• Water (H2O) is a polar molecule because its
  hydrogen end is slightly positive and its oxygen
  end is slightly negative.

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SPECIFIC HEAT

• The amount of energy it takes to raise the
  temperature of a substance by one degree Celsius
• Water has a very high specific heat.
• This means that compared to other substances, it
  takes a big change in energy to change the
  temperature of water.
• Example The ocean does not drastically change
  temp.

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SURFACE TENSION

• Definition
• the force that acts on the particles at the
  surface of a material
• Example
• Water striders (bugs)
• painful belly flop

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UNIVERSAL SOLVENT

• Water is called the universal solvent
• Definition
• this means that water can dissolve more things
  than any other substance.
• Example
• water can dissolve soap, sugar, salt,
  toothpaste, baking soda, etc.

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Acting it out

• Students will be divided into pairs.
• Each pair will be given one of the properties of
  water to act out.

Words Adhesion Buoyancy Capillary
Action Cohesion
Density Polarity Specific Heat Surface
Tension Universal Solvent
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Assessment Statements

• The water is sticking to the side of the glass.
• adhesion
• 2. Water droplets combine together in the
  atmosphere to make rain drops.
• cohesion
• 3. Salt dissolves in water.
• universal solvent
• 4. When I dropped a rock in the river, it sank.
  
• buoyancy
• 5. On the coast in the summer, the ocean takes a
  lot longer to heat up than the air and land.
• specific heat
• Water molecules have a positive end and a
  negative end.
• polarity

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Water Properties Practice

1. The suction cup will only stick to the window if
   I wet it first.
2. My mom used water to make Gatorade for the team.
   All of the powder dissolved completely in water.
3. Water striders are able to walk on water without
   sinking.
4. I tried to mix the oil with the water, but no
   matter what I did the two liquids would not mix.
5. The window was covered in rain. As the rain ran
   down the window, the drops came together to make
   larger drops of water.
6. Ginas doctor suggested that she join a water
   aerobics class for exercise to keep from
   re-injuring her knee. He told her that the water
   takes the pressure off of her knee.
7. The paper towel soaked up the spill in a jiffy.
8. The log floated down the river.
9. The blue dye in the water traveled up to the
   petals of the white flower.
10. An iceberg floats on water in the Artic.

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Unique Properties of Water Mini Labs

1. Sinkn Lincoln
2. Water bug
3. Water Rope
4. Iceberg
5. Shipwreck

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Sinkn Lincoln

• Predict how many drops of water you can fit on a
  penny.
• What was the actual number of drops you could fit
  on the penny?
• What property of water allowed you to fit that
  many drops on the penny?

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Water bug

• 4. A paper clip is not lighter than water, yet it
  can stay on top of the water. Explain why this
  is.
• 5. Explain what the soap did to the surface
  tension of the water.

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Water Rope
6. What is capillary action? How does this help
plants?
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Iceberg
7. Why does ice float on top of water? 8. Rank
the densities of the liquids from most dense to
least dense. 9. If waters density is 1.0 g/mL,
what can be determined about the other liquids
densities in the column?
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Ship Wreck

• 10. Does the density of the boat affect the
  buoyancy?

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How Stuff Works WATER

• What is a dipole? How does waters dipole
  molecular structure affect its properties?
• Why is water essential to life on earth? Why do
  scientists credit water with allowing life to
  form?
• How do plants transport water from the roots to
  the leaves?
• How does the Hoover Dam generate electricity?
  What are the environmental drawbacks of damming a
  river?
• Why does water resist compression?
• What is cloud seeding? How does cloud seeding
  encourage rainfall?

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