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Grade Level: 5 – 6
Purpose:
To introduce various types of weathering and erosion.
Suggested Goals:
Students will discover the effects and processes that may occur with each
type of weathering and erosion.
Targeted Objectives:
As a result of this lesson Student will be able to:
- Identify various types of weathering and erosion.
- Discover the effects that occur with each type of weathering and erosion.
Background:
Weathering refers to the group of destructive forces that change
the physical and chemical character of rock near the earth’s surface.
Mechanical weathering (or physical disintegration) is the breaking
down of rocks into smaller pieces. The change in the rock is physical
with little or no chemical change. Chemical weathering is the
decomposition of rock from exposure to water and atmospheric gases (principally
carbon dioxide, oxygen, and water vapor). As rock is decomposed by these
agents, new chemical compounds form. Examples of mechanical weathering
include: frost action, abrasion, and pressure release. Examples of chemical
weathering include: rusting, acid breakdown, and solution weathering.
Erosion is the picking up or physical removal of rock particles
by an agent such as streams or glaciers. Weathering helps break down a
solid rock into loose particles that are easily eroded. Most eroded rock
particles are at least partially weathered, but rock can be eroded before
it has weathered at all. A stream can erode weathered or unweathered rock
fragments.
Materials/Preparation:
Preparation for this is general lab preparation. This can be done as a
series of stations. Access to a freezer is needed, but it doesn’t
have to be in the room. Internet access and a computer are needed.
Materials needed include:
- carbonated water
- overhead markers
- ziplock bags
- tap water
- pennies
- sugar cubes
- baby food jars (6 per group)
- vinegar
- shallow pan
- rock samples
- antacid tablets
- ice cubes
- plastic glasses
- mortar and pestle
- sand
- chalk
- steel wool
- gravel
Part I: Weathering Stations
Procedure:
Introduce and review types of weathering. Discuss the differences between
the weathering. Showing pictures is helpful. Also showing pictures of
each process and effect is helpful. [Web sites listed have pictures.]
Perform weathering lab stations. In the weathering stations the following
activities are used. One station for each activity. Lab sheets for each
station are included in the PDF download version
of this lesson.
- Station 1. Test rock samples in carbonated water vs. tap water. Observations
are taken initially, at 20 minutes, and after 24 hours.
- Station 2. Test to show that water expands as it freezes. Mark on
a cup the water level before freezing and after freezing.
- Station 3. Test the effects of vinegar (acid rain) on copper (pennies).
Here you should record observations initially and then after 5 minutes.
- Station 4. Compare and record the reaction of antacid tablets in water.
The comparison is a whole tablet vs. crushed tablet.
- Station 5. Compare and record the reactions of chalk (limestone) in
water and vinegar.
- Station 6. Test and record the effect of water on steel wool.
- Station 7. Test and record the effects of sugar cubes and gravel shaken
together in a jar.
Discuss lab and effects of each process. Reinforce the processes and
make connections to Illinois with pictures.
Discussion Questions:
- How does weathering and erosion occur?
- What is the result of each type of weathering?
- Where on earth or where in Illinois does this happen?
Part II: Erosion Stations
Procedure:
Introduce and review types of erosion. Discuss the differences between
erosion and weathering. Showing pictures is helpful. Also showing pictures
of each process and effect is helpful. [Web sites listed have pictures.]
Perform erosion stations. In the erosion stations the following activities
are used. One station for each activity.
- Station 1. Demonstrates beach erosion. Using a pan, make a sand pile
at one end and pour water at the other end. Slide the pan back and forth
to create wave movement. Record observations.
- Station 2: Place an ice cube in a plastic cup of warm water. See what
the effect is. Record observations.
- Station 3: Freeze ice cubes with sand in them and then move the sand
ice cubes over different surfaces, sand, water, dirt, etc. Record observations.
- Station 4: Place sand in a small bowl and the use a hair dryer to
move the sand. Note if different speeds are possible. Record observations.
- Station 5: Place a pile of ice cubes on a mound of dirt. Observe and
record what happens as it melts.
Discussion Questions:
- How does erosion occur?
- What is the result of each type of erosion?
- Where on earth or where in Illinois does this happen?
Extensions:
- Rock Cycle Game (see lesson 6.4: Ride
the Rock Cycle)
- Students could create a presentation of various types of erosion and
weathering in the United States or Illinois.
Assessment:
- Slide presentation on Internet
- Grading of lab sheets
- Evaluate presentations of erosion and weathering examples.
Lesson Specifics:
- Skills-Students will need to use observation, inference, data collection
skills to complete the lab stations. Also, the students will need to
use the Internet and a computer to access the assessment.
- Duration- 2 to 3 days
- Group size- Project may be completed individually or in groups of
3 or 4
- Setting- Classroom and computer lab with Internet access
Illinois State Board of Education Goals and Standards:
- 12.E.3b: Describe interactions between solid earth, oceans,
atmosphere and organisms that have resulted in ongoing changes of Earth.
- 17.B.3a: Explain how physical processes including climate,
plate tectonics, erosion, soil formation, water cycle, and circulation
patterns in the ocean shape patterns in the environment and influence
availability and quality of natural resources.
Web Resources:
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