I. Grade Level/Unit Number: 8th Grade / Unit 3
II: Unit Title: Amazing Water
III. Unit Length: 3-4 weeks
IV. Major Learning Outcomes: The student will be able to . . .
a. Predict the solubility of a substance in water based on polarity.
b. Explain water’s unique ability as the universal solvent.
c. Predict whether a substance will float in water based on density.
d. Classify an object based on its density relative to that of water.
e. Determine if water is demonstrating cohesive or adhesive forces.
f. Analyze real-world situations that involve density and buoyancy.
g. Explain the unusual nature of ice’s density versus water’s density.
h. Describe the location of water on earth.
i. Understand that the water on earth is the same water that has been here for billions of years.
j. Explain the processes by which water moves from one location to another via the water cycle (processes include transpiration, condensation, runoff, groundwater, and evaporation).
k. Describe, based on percentages, the amounts of water in each location.
l. Describe types of technology or processes that can be used to convert unusable water to usable resources.
m. Understand that water is a limited resource that needs to be conserved.
n. Describe the structure of the hydrosphere including watersheds, river basins, standing bodies of water (lakes and ponds), rivers and streams, wetlands, and the ocean.
o. Describe technology used to study the hydrosphere.
V. Content Objectives Included:
Number / Competency or Objective / RBT Tag3.01 / Analyze the unique properties of water including:
· Universal solvent.
· Cohesion and adhesion.
· Polarity.
· Density and buoyancy.
· Specific heat. / B2.3 (classifying)
B4.2 (outlining)
3.02 / Explain the structure of the hydrosphere including:
· Water distribution on earth.
· Local river basin.
· Local water availability. / a4.2 (explain)
3.06 / Evaluate technologies and information systems used to monitor the hydrosphere. / c5.2 (evaluate)
VI. English Language Proficiency (ELP) Standard 4 (2008)- for Limited English Proficient students (LEP) English language learners communicate information, ideas, and concepts necessary for academic success in the content area of SCIENCE.
VII. Materials / Equipment Needed:
Part I / test tubestest tube rack
graduated cylinder
beakers (small—50 mL and large—250 mL)
medicine droppers
plastic shoe boxes
balance
water
alcohol (both 70% and 91%)
oil (mineral and canola)
sand
salt
flour
cornstarch
sugar
soap flakes
aluminum foil
pennies
wax paper
paper towels—not brown school paper towels
small hard plastic object
small wooden object
can
tape—masking
fabric samples—cotton, linen, wool, silk, polyester, blend, rayon,
nylon, and chamoise
Part II / chart paper
markers
water cycle clues and signs—provided
graduated cylinders
calculators
calibrated droppers or pipettes(calibrated for 1 mL)
2-liter bottles
food coloring
large paper or poster board
research Materials—encyclopedias, Internet, and textbooks
Part III / white paper
white cardstock
tape
water soluble markers
shallow pans
water bottles
River Basin Booklets from NCDENR (free)
projector or color printer
chart Paper
internet Access with projector or individual student access
VIII. Big Ideas (from Support Document):
Water is one of the most common substances on Earth. The unique properties of water are polarity, cohesive and adhesive abilities, universal solvency, density and buoyancy, and high specific heat. Water is circulated on Earth by a process known as the water cycle. Most of the Earth’s water is found in the oceans. The majority of fresh water exists in ice caps, glaciers and aquifers. Surface water moves into river basins from areas called watersheds. The availability of water varies with local geography and allows humans to utilize water as a resource.
IX: Unit Notes:
The first part of this unit is packed with labs. The second and third parts focus more on hands-on activities and discussions. The unit moves from water’s unique properties to the location of water on earth to the specific structure of the hydrosphere and the technologies used to monitor the hydrosphere. Students have some background knowledge on the water cycle but may not have background knowledge on the specific “structures” of the hydrosphere.
For the third part, each student will need a copy of the river basin booklet published by NCDENR. These resources are free for educators and can be obtained by ordering them from NCDENR. The booklet is also available online at http://www.eenorthcarolina.org/public/ecoaddress/riverbasins/riberbasinbooklet150dpi
You will need to print the satellite images for Part 3: ELABORATE in color.
There are a series of activities available at the following website on the water cycle.
http://www-k12.atmos.washington.edu/k12/pilot/water_cycle/teacherpage.html
You can find a great resource for water lessons at the following website from the state of Queensland, Australia Department of Natural Resources and Water. There are lessons, background information, experiments, etc.
http://www.nrw.qld.gov.au/waterwise/education/units/introduction.html
X. Global Content and 21st Century Skills:
NC SCS
Grade 8
/ 21st Century Skills / ActivityCommunication Skills
1.01,1.02, 1.08
6.03, 7.01 / Conveying thought or opinions effectively / Take a Stand Activity
1.05,1.10 / When presenting information, distinguishing between relevant and irrelevant information
1.04 / Explaining a concept to others / Turn and Talk Activity, Frayer Models
Interviewing others or being interviewed
Computer Knowledge
1.09 / Using word-processing and database programs
1.07 / Developing visual aides for presentations / Water Cycle Diagram
Technology Ad
1.08 / Using a computer for communication
2.04 / Learning new software programs
Employability Skills
1.02 / Assuming responsibility for own learning / All Labs and Research
Persisting until job is completed / All Labs and Research
1.03 / Working independently / Research, Frayer Models
7.05 / Developing career interest/goals
1.08 / Responding to criticism or questions
Information-retrieval Skills
1.09
3.06, 5.04, 5.05, 7.05 / Searching for information via the computer / Research for processes that convert unusable water, water witching activity
Technology Ad
1.08
7.05 / Searching for print information / Research for processes that convert unusable water
1.09
2.02, 7.05 / Searching for information using community members
Language Skills - Reading
1.03, 1.05 / Following written directions / All labs
1.05, 3.08
4.08, 4.09, 4.10, 5.02 / Identifying cause and effect relationships / Using remote sensing to study the effects of flooding along NC coast
1.10
6.04 / Summarizing main points after reading / Frayer Models
1.07
1.08 / Locating and choosing appropriate reference materials / Research for processes that convert unusable water
1.10 / Reading for personal learning
Language Skill - Writing
5.02, 7.02 / Using language accurately
1.07
1.08
1.10 / Organizing and relating ideas when writing
1.10 / Proofing and Editing
2.04
7.05 / Synthesizing information from several sources / Research for processes that convert unusable water
1.10 / Documenting sources / Technology Ad
2.03 / Developing an outline
1.05 / Writing to persuade or justify a position / Promoting the processes for converting unusable water
1.09 / Creating memos, letters, other forms of correspondence
Teamwork
1.01
1.05 / Taking initiative
Working on a team / All Labs
Thinking/Problem-Solving Skills
1.02, 4.05,
4.07, 4.08,
5.02, 7.03 / Identifying key problems or questions / Processes for converting unusable water, types of technology to monitor hydrosphere activity
1.05, 1.07,
1.10, 2.03,
4.02 / Evaluating results / All Labs
1.06, 3.01,
3.05, 5.04,
5.05, 6.02
7.03 / Developing strategies to address problems / Researching and developing processes for converting unusable water
1.09 / Developing an action plan or timeline
Unit 3:
Amazing Water
CONTENTS
§ Part I: The Unique Properties of Water 7
§ Part II: Distribution of Water 33
§ Part III: The Structure of the Hydrosphere 50
§ Multiple Choice Questions 66
Amazing Water
Part 1: The Unique Properties of Water
PURPOSE: To investigate the unique properties of water.
GOAL / OBJECTIVE:
Goal 1 –The learner will design and conduct investigations to demonstrate an understanding of scientific inquiry.
Objectives 1.01, 1.05, 1.08, 1.09, 1.10
Goal 2 - The learner will demonstrate an understanding of technological design.
Objective 2.02, 2.03, 2.04
Goal 3 - The learner will conduct investigations and utilize appropriate technologies and information systems to build an understanding of the hydrosphere.
Objective 3.01
Engage:
Place a couple pieces of ice in a beaker of water. Give students 3-5 minutes to brainstorm on paper why ice floats. Remind the students that almost all pure solids are more dense than their corresponding pure liquids. After allowing students to brainstorm on paper, ask students to “turn and talk” about their ideas.
“Turn and Talk” is a strategy that allows students to partner with one person and share ideas. Give the first partner 1 minute to share his ideas while the second partner listens. Then, allow 1 minute for the second partner to share his ideas.
Next, as a class, come up with an explanation as to why ice floats. Lead students to the idea that water expands when it freezes, thus trapping air. Hence, ice is less dense than water. This is a unique property of water.
Explore:
Students will perform six mini-labs in stations that introduce and reinforce the unique properties of water. Students should record their information on the data sheet and answer the analysis questions. The directions are available in station cards. These labs may take 2-3 days.
Note to Teacher: Be sure to cut the aluminum for Station 4 the same size. You will need to prepare the can for Station 7 using a hammer and nail to punch 2 small holes on the side of the can along bottom edge. The holes should be about one-half inch apart.
Explain:
Have the student complete the Frayer Model (adapted from Frayer, D., Frederick, W.C., and Klausmeier, H.J. (1996). A Schema for Testing the Level of Cognitive Mastery. Madison, WI: Wisconsin Center for Education Research.) for each concept using available resources. The students will give a definition, a visual (sketch) to associate with the term, 3 real-world examples, and a sentence using the concept. You should model the process with the first Frayer Model as a class. A transparency for the first one is provided.
Encourage students to use specific examples from the labs we have conducted or from their own experiences.
*In the end, students should have a clear understanding of each concept and a visual image to allow for recognition.
Concepts:
8th Grade Unit 3 79
Universal Solvent
Cohesive Forces
Adhesive Forces
Polarity
Density
Buoyancy
Surface Tension
Capillary Action
8th Grade Unit 3 79
Elaborate:
Tell the students they are working for a textile company to make tents (guys) or handbags (girls). To gather data, they must test known fabrics for water absorbency to see if water adheres to the fabric. Then, they must determine if man-made fibers or synthetic fibers work the best.
Ask the students to complete the activity sheet. They may need to do research to determine if the fibers are natural or man-made.
Evaluate:
Ask the students to identify the property of water from various scenarios. See attached student sheet of scenarios.
Additional Resources
USGS website on water properties
http://ga.water.usgs.gov/edu/waterproperties.html
Student Reading and Experiments – WOW Curriculum sponsored by NSF
http://waterontheweb.org/curricula/bs/student/water/unique.html
Background Information on properties of water
http://www.epa.state.il.us/water/conservation-2000/lake-notes/lake-stratification-and-mixing/the-unique-properties-of-water.html
Student Reading and Background Information – more detailed
www.ccpo.odu.edu/~arnoldo/hightide/LESSONS/StudentReadingTheUniquePropertiesofWater.doc
ENGAGE, Part 1
Transparency
Turn and Talk
You will partner with your neighbor. When I say go, partner A will discuss his/her understanding of the question while partner B listens. When I call time, partner B will share his/her understanding of the question and partner A will listen.
EXPLORE, Part 1
Station Directions
EXPLORE, Part 1
Station Directions
EXPLORE, Part 1
EXPLORE, Part 1
EXPLORE, Part 1
EXPLORE, Part 1 Name ______
Handout Date ______
Unique Properties of Water
Station Lab Data Collection and Analysis Sheet
Station 1: Water—The Universal Solvent
Data:
Substance / Prediction / Data on SolubilityAlcohol
Oil
Sand
Salt
Flour
Cornstarch
Sugar
Soap Flakes
Analysis:
1. Did all of the substances dissolve in water? If no, which substances did not dissolve in water?
2. Water is a polar molecule. What does this mean?
3. What can we determine about the polarity of the substances based on the solubility of each substance?
4. Does water’s polarity help it to act as a universal solvent? Why or why not?
5. How does water’s ability to be a universal solvent help us in our everyday life?
Station 2: Polar Pals
Data:
Beaker
/ ObservationsBeaker 1
Beaker 2
Beaker 3
Analysis:
1. Which substance was soluble in water? Why?
2. Which substance was insoluble in water? Why?
3. Did the liquids in the last beaker mix? Why or why not?
Station 3: Sinkin’ Lincoln
Data:
Substance
/ Prediction of Number of Drops before Overflow / Actual Number of DropsBefore Overflow
Plain Water
Soapy Water
Sketch:
Analysis:
1. Surface tension is created by forces between molecules. Are the forces cohesive or adhesive? Explain your answer.
2. What did the soap do to the surface tension of the water? Explain your answer.
3. How does surface tension explain the pain a swimmer feels when he jumps off the diving board and does a belly buster?
Station 4: Passengers in a Boat
Data:
Measurement / Boat 1 / Boat 2 / Boat 3 / Boat 4 / Boat 5Number of pennies needed to sink boat
Mass of empty boat
Mass of boat and pennies
Volume of boat
Density of empty boat
Density of boat with pennies
Sketch:
Analysis:
1. What is buoyancy and how does it relate to this lab?
2. Does the mass of the boat affect the buoyancy? Why or why not?
3. How are the concepts of buoyancy and density used to design boats that will float on water?
Station 5: A Density Column
Data:
Object / ObservationsWooden Object
Plastic Object
Aluminum Ball
Sketch:
Analysis:
1. If water’s density is 1.0 g/mL, what can be determined about the other liquids’ densities in the column?
2. Rank the densities of the liquids and the solids from most dense to least dense.
3. Using this information, explain how the Titanic could float on water.
Station 6: Capillary Action
Data:
Beaker
/ Observations1
2
3
Analysis: