Transcript Unit 7 - AGoswick

Unit 2 Day 3
Physical & Chemical Weathering
Warm-Up
• Imagine dropping a sugar cube into a cup of
coffee and the same sugar cube into a cup of
cold lemonade.
1) In which cup do you predict the sugar cube
will dissolve first? Why?
2) What could you do to make the sugar cube
dissolve faster?
Unit 1 Test Corrections
• Must be completed independently (may use
your notebook)
• Must provide the CORRECT letter & write out
your answer as a complete sentence with an
explanation to receive credit.
– E.g. C-The number of pink flowers was the
dependent variable, BECAUSE this is what was
being measured in the experiment.
• May complete corrections during A lunch, 1st
period (with prior permission & pass), during
work time (with permission), after school
Announcements
• Must turn in your Rock Cycle Crayon Lab &
Rock Cycle half sheet today, if you have not
already done so
• Notebook check for Unit 1 Completed
– Grade based on organization
– Completion (thorough notes)
– Do Now/Exit Tickets stamped & in complete
sentences
• Be sure all work is stapled, taped, or glued
into your notebook
• Must take Unit 1 Test before Friday!
• Daily Goal: SWBAT explain differences in chemical
and physical weathering.
• Big Goal: 80% mastery, college-level work, and
global awareness!
Key Terms
• Physical Weathering
• Chemical Weathering
• Biological Activity
• Unloading
• Frost Wedging
Agenda
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Warm Up
Weathering video + Real-world application
Smarties demo
Weathering Lab
Notes: Weathering
Start on Homework, if time…
Exit Ticket
Weathering…why do we care?
Weathering steels are high strength, low alloy
steels that can provide corrosion protection
without additional coating. Increase in alloying
elements, primarily copper, stops atmospheric
corrosion in the material itself.
The material was developed in the 1930s for
use in coal hopper train cars to resist the corrosive
effects of the sulfur in coal and exposure to long
periods of rain. Experience at the time found that
conventional steel was corroding in relatively short
periods of time. What sets the material apart
from conventional steel is in the chemistry.
Weathering steel will have a minimum copper
content of at least 0.20 percent, whereas
conventional carbon steels have a copper content
of less than .02 percent
Physical Weathering Video
• While you watch, write down at least 3
BULLETED NOTES below your DO NOW
How Does Surface Area affect the
Rate of Weathering?
• Demo: Smarties and acid
• Create a hypothesis: Which smarties do you
think will dissolve the quickest?
• Write your Conclusion
Chemical Weathering Video
-Below your sweet tart experiment conclusion,
write 3 BULLET POINTS (MAIN IDEAS) about
this video
-Pay close attention to the information about
climate and the effects of climate on
weathering
Weathering Lab
PROBLEM: How does the environment affect the rate of chemical weathering?
RESEARCH: Use your notes and page 129-131 in the text book to answer the
following questions:
1) What is chemical weathering?
2) What is physical weathering?
3) How does chemical weathering differ from physical weathering?
4) What are some factors that affect the rate (speed) of chemical weathering?
10 minutes!
Hypothesis
At which temperature will chemical weathering
occur the fastest? (If…then)
Make an educated guess based on the research
you’ve already done!
Experiment: Part 1
1. Fill the container of rocks about half full with water. Make
Observations about the water, container, and rocks.
2. Place the lid on the container and shake the container
vigorously 100 times.
3. Pour your water, but not your rocks into your beaker.
4. Make observations of the water in the beaker and the sides of
the plastic container after shaking.
5. Pour the rest of your water back into the plastic container and
begin part 2.
Part 1 Observations
Before Shaking
After Shaking
Experiment: Part 2
Temperature
 10-20oC
 20-30oC
 30-40oC
 40-50oC
What might you need
to use to get to the
proper temperature?
Sharing your data…
Starting
Temperature
(oC)
Dissolving
Final
Time (seconds) Temperature
(oC)
Average
Temperature
Data
Title: ____________________________________________
Analysis and Conclusion
Use your data and observations to complete your
analysis and conclusion (15 minutes)
**I SHOULD HEAR ONLY TALK ABOUT THIS LAB!
**YOU SHOULD BE WORKING AND COLLABORATING
with your lab group.
Let’s take a deeper look…
Frost Wedging
When water freezes
and expands, it
enlarges cracks in
rocks.
What happens when you freeze a coke
can?
• The liquid expands, and often times the can
will bust!
Chemical Weathering
Frost Wedging
Biological Activity
Unloading
Devil’s Tower, Wyoming
• First National Monument
– Devils Tower was the first declared United States
National Monument, established on September
24, 1906 by President Theodore Roosevelt.
• What is it?
– Devils Tower is a monolithic igneous intrusion, or
in other words, it is the core of a volcano exposed
from erosion
• How do you think Devil’s Tower formed?
HOMEWORK
• Begin silently working on the homework
(Worksheet 2.3)
Exit
Ticket
1) In which type of climate would chemical weathering occur the fastest?
A. warm and dry
B. cold and dry
C. warm and wet
D. cold and wet
2) Which of the following are not a type of mechanical weathering?
A. Uploading
B. Biological Activity
C. Cutting
D. Frost Wedging
3) We learned from the lab today that as the temperature increases, the rate of
chemical weathering ________.
A. increases
B. decreases
C. stays the same
D. increases then decreases
4) Students placed rock chips of
uniform size and shape in jars halffilled with water and shook them
for different lengths of time. One
rock chip was collected for each
length of shaking and displayed.
Which column above shows the rock chips arranged from top to bottom in order of
least to most shaking time? Explain your reasoning.