unique properties of water mrs. mcaven 8 th grade science riverwood middle school

Unique Properties of

WaterMrs. McAven

8th Grade ScienceRiverwood Middle School

The Properties of WaterCH.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.

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!

VOGOSide 1

WORD• Definition

Side 2

• Example/Sentence• Picture

Words:

AdhesionBuoyancyCapillary ActionCohesion

Density PolaritySpecific HeatSurface TensionUniversal Solvent

Where can I find these words? Chapter 2 (pg. 44)

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

BUOYANCY

Definition: • the ability of an object to float in water.

Example:• floating in the ocean or a pool• a boat

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

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

DENSITY

Definition: • the measure of mass of a substance per unit

volume

Example:• ice floating on water

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.

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.

SURFACE TENSION

Definition: • the force that acts on the particles at the

surface of a material

Example:• Water striders (bugs)• painful belly flop

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.

Acting it out• Students will be divided into pairs. • Each pair will be given one of the properties of

water to “act out.”

Words:

AdhesionBuoyancyCapillary ActionCohesion

Density PolaritySpecific HeatSurface TensionUniversal Solvent

Assessment Statements1. The water is sticking to the side of the glass.

adhesion2. 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. density

5. On the coast in the summer, the ocean takes a lot longer to heat up than the air and land. specific heat

6. Water molecules have a positive end and a negative end. polarity

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. Gina’s 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.

Water Properties Practice

Unique Properties of Water Mini Labs

1. Sink’n Lincoln2. Water bug3. Water Rope4. Iceberg5. Shipwreck

Sink’n Lincoln1. Predict how many drops of water you

can fit on a penny.

2. What was the actual number of drops you could fit on the penny?

3. What property of water allowed you to fit that many drops on the penny?

Water bug4. 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.

Water Rope

6. What is capillary action? How does this help plants?

Iceberg7. Why does ice float on top of water?

8. Rank the densities of the liquids from most dense to least dense.

9. If water’s density is 1.0 g/mL, what can be determined about the other liquids’ densities in the column?

Ship Wreck10. Does the density of the boat affect the buoyancy?

Buoyancy and the Titanic MythBusters: Water Displacement

How Stuff Works: WATER1.What is a dipole? How does water’s dipole molecular

structure affect its properties?2.Why is water essential to life on earth? Why do scientists

credit water with allowing life to form?3.How do plants transport water from the roots to the

leaves?4.How does the Hoover Dam generate electricity? What are

the environmental drawbacks of damming a river?5.Why does water resist compression?6.What is cloud seeding? How does cloud seeding encourage

rainfall?

How Stuff Works: WATER