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Monday, October 17

  1. page Day 03 - Chemical Engineering - Glue edited {A5_1_2GluingItAllTogether.doc} {design_process.ppt} Activity 5.1.2 Gluing It All Together …
    Activity 5.1.2 Gluing It All Together
    The first commercial glue, created around 1750, was made from fish. Other early adhesives used natural rubber, animal bones, blood, starch, and milk protein or casein. Today animal glues have mostly been replaced with cheaper synthetic glues made from manmade chemicals synthesized from petroleum and natural gas.
    When milk and vinegar are mixed together, the vinegar makes the protein in the milk, called casein, stick together to form small white lumps called curds. The leftover liquid is called whey; you will make the glue from the curds. When you add glue between two pieces of paper, the glue seeps into tiny cracks in the papers. When the glue hardens, it forms a bond to hold the paper together. In real life, engineers design special glues when they need to hold things like envelopes, sneakers, and even airplanes together.
    In this activity you will use the internet to research glue, and then use the information to evaluate bonds made with your homemade glue.
    Engineering notebook
    Computer with Internet access
    Measuring cups and measuring spoons
    Paper, felt, cardboard, popsicle sticks, craft foam, magazine(slick) paper, variety of paper plates, wax coated paper cups
    Safety goggles
    Hole punch
    Masking tape
    Ingredients for each batch of glue:
    ¼ cup hot tap water
    2 tablespoons powdered milk
    1 tablespoon vinegar
    3 large paper cups
    5 paper towels
    1 rubber band
    Plastic spoon
    ¼ teaspoon baking soda
    1 teaspoon hot water
    ¼ cup flour
    Use any of the websites listed below to find the answers to the following questions:
    1. What are considered to be among the earliest adhesives?
    2. What animals, or parts of animals were used to make glues?
    3. What is the “technical” name for “super glue” type adhesives?
    4. What are the two requirements for glue to “work” (form a bond between two materials.)
    5. Explain the difference between adhesion and cohesion.
    6. It is thought that bonding of adhesives occurs at the molecular level. What is the technical name of the force which holds glue to its bonding materials?
    7. What type of molecule is important for this “force” to be effective in bonding?
    8. Why do “super glue” adhesives bond to skin?
    9. List three types of “adhesives” that do not resemble traditional liquid or semi-solid adhesives.
    10. Explain one of the theories on how Post-It® notes work?
    11. How do geckos climb on everything?
    Making the Glues:
    Your teacher will divide the class into engineering teams of 2 - 3 students. Each team will make and test two different glues on several different substrates, then compare the results.
    Casein Glue
    Mix the hot water and powdered milk. Stir until dissolved.
    Put the vinegar into the cup holding the milk. Stir for about 30 seconds. The milk will begin to separate into solid curds and watery whey. Continue stirring until the milk is well-separated.
    Make a strainer to separate the curds from the whey. Put a folded paper towel or coffee filter over one of the large paper cups. Push down in the center to form a bowl shape. Put a rubber band around the top of the cup to hold the paper towel.
    Pour the curds and whey into the strainer.
    Wait about 5 minutes for all of the whey to drip through. Use a spoon to carefully scoop out the curds and put them on a clean paper towel.
    Put another paper towel on top of the curds and gently press down. Soak up the remaining liquid until the curds feel firm, not squishy.
    Put the curds in a clean paper cup. Add about 1 teaspoon of water to the curds and stir.
    Add the baking soda and stir. Some foaming may occur from the carbon dioxide gas being released when the baking soda and vinegar mix.
    9. Mix thoroughly until the glue becomes smooth and more liquid. If the mixture is too thick, add a bit more water. If the glue is too lumpy, add more baking soda.
    Flour and Water Paste
    In a small bowl or cup, mix flour with enough water to make a smooth, creamy mixture.
    Add a pinch of salt; and stir.
    Testing the Glue:
    Cut 1 in. x 8 in. strips of substrate material (if foldable) or two 1 in. x 4 in. strips if the material cannot be folded. Measure two inches from one of the edges, and make a mark where you will place the glue. Dip the end of a toothpick into your glue so you use the same amount of glue on each paper strip. Place a very small dot of glue on the 2” mark. Fold the substrate in half if possible, or put a second piece of the same substrate on top, and press on the location of the adhesive. Clamp the bonds, or place weights on them. Make a duplicate bond using the same material and glue.
    Repeat the procedure for each type of material provided to you by your instructor.
    Let strips dry until next class.
    Make a test cup by poking holes on opposite sides of a small paper cup and taping a string to the holes for a handle.
    Reinforce one end of the test material with masking tape, and then punch a hole in it approximately 1” from the end. Attach the string with cup to the strip with the hold using a paper clip. Hold the top strip with your fingers.
    Drop pennies one at a time into the cup until the strip pulls apart. This is testing the adhesive in a “peel” configuration. Count the pennies and record the results in your GTT notebook. Describe the failure (ex: the material tore apart, or the glue let loose.)
    Repeat for each test substrate and adhesive.
    Number of Pennies held with Casein Glue and description of bond failure
    Number of Pennies held with Flour Glue and description of bond failure.
    1. Which adhesive gave better bonds overall?
    2. Explain which adhesive you would use if you had to build a toothpick bridge?
    3. In the glue making process describe the role of a chemist and the role of a chemical engineer.
    4. Explain how you used the design process to design, prototype, and test your glue.
    Design Process Step
    What We Did at This Step:
    Define the Problem
    Develop Ideas
    Choose Best Idea
    Model or Prototype
    Test and Evaluate
    Improve Design
    Communicate Results
    Optional: Read The Glue Test from this website: **** Why is it important to test the materials you are using to solve an engineering problem?

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  2. 8:17 pm
  3. page Day 01 - Introduction edited {D11_CTE_PermissionForm wMedia Rel.doc} NOTE * Remember that you can use the Narrator feature f…
    {D11_CTE_PermissionForm wMedia Rel.doc}
    NOTE * Remember that you can use the Narrator feature from Start - Programs - Accessories - Accessibility to read text files in Notepad. Just highlight the text from a document or webpage source file and past it into Notepad. Enable Narrator and follow along as the computer reads the text to you through your headphones!

    Lesson 5.1 Applied Chemistry
    Perspective - Students will determine the best use of their resources to clean up an oil spill.
    Self-knowledge - Through participation in group activities, students will understand and appreciate the importance of good communication skills, teamwork skills, and workforce development skills.
    Essential QuestionsQuestions**
    1. What does a chemical engineer do?
    2. What is the difference between a chemical engineer and a chemist?
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    8:07 pm
  4. page Day 02 - Chemical Engineering - Ice Cream edited Chemical Engineering - Lowering the Freezing Point {A5_1_1IceCream.doc} Activity 5.1.1 Let’s…

    Chemical Engineering - Lowering the Freezing Point
    Activity 5.1.1 Let’s Make Ice Cream
    Suppose you have a great recipe for chocolate ice cream. You like to make it at home for your family and friends. You make it in a little one-gallon machine that goes into your freezer. But what if you sell your recipe to a big food company? Now they have to be able to make thousands of gallons a day. Each gallon of ice cream needs to look and taste exactly the same. What kind of equipment could the company use? How would the recipe change? How can the factory make the ice cream at low cost? These are all questions for the chemical engineer.
    Ice must absorb energy in order to melt, changing the phase of water from a solid to a liquid. When you use ice to cool the ingredients for ice cream, the energy is absorbed from the ingredients and from the outside environment (like your hands, if you are holding the baggie of ice). When you add salt to the ice, it lowers the freezing point of the ice, so even more energy must be absorbed from the environment in order for the ice to melt. This makes the ice colder than it was before, which is how your ice cream freezes.
    You could use other types of salt instead of sodium chloride (NaCl), but you couldn't substitute sugar for the salt because (a) sugar doesn't dissolve well in cold water, and (b) sugar doesn't dissolve into multiple particles. Compounds that break into two pieces upon dissolving (e.g., NaCl breaks into Na+ and Cl-) are better at lowering the freezing point than substances that don't separate into particles. This is because the added particles disrupt the ability of the water to form crystalline ice. The salt causes the ice to absorb more energy from the environment (lowering the freezing point), so although it lowers the point at which water will re-freeze into ice, you can't add salt to very cold ice and expect it to freeze your ice cream or de-ice a snowy sidewalk (water must be present). This is why NaCl isn't used to de-ice sidewalks in areas that are very cold.
    In this activity you and a partner will make and eat ice cream. Notice how the salt affects the melting point of the ice.
    GTT notebook
    Measuring cups and measuring spoons
    Bucket or sink to dump ice in when ice cream is made
    The following ingredients are needed for each group of 2 students:
    ½ cup milk
    ½ cup whipping cream (heavy cream)
    ¼ cup sugar
    ½ - ¾ cup NaCl (sodium chloride) as table salt or rock salt
    1 quart-size bag
    1 gallon-size bag
    3 cups ice
    ¼ teaspoon vanilla for vanilla ice cream
    1 tablespoon strawberry syrup – omit ½ of the sugar for strawberry ice cream
    1 tablespoon chocolate syrup – omit ½ of the sugar for chocolate ice cream
    You and your partner need to determine which flavor ice cream you will be making. If you are making chocolate or strawberry ice cream, use only 2 tablespoons of sugar.
    Pour the milk, whipping cream, sugar, and (vanilla, chocolate, or strawberry) into the small Ziploc bag. Squeeze as much air out as possible and seal the bag.
    You may want to save adding the sugar for last because it varies depending upon the flavor of ice cream chosen.
    Make sure the bags aren’t leaking. Double bag if necessary.
    Fill the gallon size bags a quarter full with ice (about 3 cups).
    Use a thermometer to measure the temperature of the ice in the gallon bag and record the temperature in Conclusion Question 1 below.
    Add the salt to the bag of ice
    Place the sealed quart bag into the gallon bag and seal securely.
    Your teacher will assign your group the mixing method that you will use to make your ice cream. Examples of mixing methods include:
    Gently knead
    Shake violently
    Flip over and over
    Rock back and forth
    Carefully toss (make sure you catch)
    Leave on table and push back and forth on sides
    Continue to mix the contents of the bag until the contents of the quart bag have solidified into ice cream.
    Record your mixing method and the time it took in Conclusion Question 2.
    Open the gallon bag and use the thermometer to measure and record the temperature of the ice/salt mixture in Conclusion Question 4.
    10.Once done, put your ice bags in the bucket or sink
    11.Divide your ice cream bag into two cups and eat your ice cream!
    1. What is the temperature of the ice?
    2. What mixing method did your group use and how long did it take to make ice cream?
    3. How does the texture of your ice cream compare to other students in the class who used a different mixing method?
    4. What is the temperature of the ice and salt after you have made ice cream?
    5. How can melted ice be colder than an ice cube?
    6. What does the salt do to the ice?
    7. How does your ice cream taste compared to what you can buy in the store?
    8. How could a chemical engineer help you if you wanted to sell this recipe so you could make thousands of gallons of ice cream a day?

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    8:01 pm
  5. 7:56 pm
  6. page Day 01 - Introduction edited {D11_CTE_PermissionForm wMedia Rel.doc} Lesson 5.1 Applied Chemistry Preface Chemical enginee…
    {D11_CTE_PermissionForm wMedia Rel.doc}
    Lesson 5.1 Applied Chemistry
    Chemical engineering is the profession that combines chemistry and engineering concepts to help solve problems related to world hunger, pollution of our environment, creating new materials, or meeting demands for energy. Chemical engineers develop low cost processes for producing ammonia, which make it possible for both poor nations and the United States to manufacture important fertilizers. They are instrumental in the production of virtually all pharmaceuticals as well as life-saving devices such as the artificial kidney or angioplasty catheters. They are working on ways to recycle plastics, reduce pollution, and develop new sources of environmentally clean energy. Chemical engineers have the background knowledge of chemistry coupled with an understanding of chemical processing that allows them to tackle most any chemical problem, from waste minimization, to environmental remediation, to pollution prevention, to clean-up of stack gases, or to purification of drinking water. Most major chemical companies hire chemical engineers to fill their technical positions in environmental engineering.
    1. Chemical engineering is concerned with design, construction and operation of machines that perform chemical reactions, separations or mixes, and fluid flow to solve problems and make useful products.
    2. Chemical engineers apply the knowledge and discoveries of a chemist to solve real life problems.
    3. Chemical engineers work in many industries including manufacturing, pharmaceuticals, healthcare, environmental, materials, and alternative energy.
    4. Chemical engineers often work on teams with other engineers, scientists, and technologists
    Performance Objectives
    It is expected that students will:
    • Describe the difference between a chemist and a chemical engineer.
    • Apply science and engineering skills to make ice cream.
    • Follow the design process to create an adhesive.
    • Work with a team to solve an oil spill engineering simulation problem.
    Interpretation - Students will describe the difference between a chemist and a chemical engineer.
    Application - Students will apply their knowledge of the design process to create an adhesive.
    Perspective - Students will determine the best use of their resources to clean up an oil spill.
    Self-knowledge - Through participation in group activities, students will understand and appreciate the importance of good communication skills, teamwork skills, and workforce development skills.
    Essential Questions
    1. What does a chemical engineer do?
    2. What is the difference between a chemical engineer and a chemist?
    3. Where would a chemical engineer work?

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    7:53 pm
  7. 7:48 pm
  8. page home edited ... Technology - Periods 1 and 7 Period 2 We are ... in Week 5 1 (Day 21 1 - Day 24),…
    Technology - Periods 1 and 7Period 2
    We are
    in Week 51 (Day 211 - Day 24),6), so click the Week 51 link on
    out this
    weeks lessons and
    Gateway to Technology - Science of Technology Syllabus
    disciplines including chemical, mechanical, civil,
    Technology in 2010-20112011-2012
    Lesson 1 Mechanics of Motion –Applied Chemistry - Students investigate and build technology innovations such as simple and compound machines and determine their societal, cultural, economic, political, and environmental consequences. They will then have anthe opportunity to designsolve problems similar to those that a chemical engineer would experience. Students will make and build an [[home#|energy conservation]] system (Rube Goldberg Device) which transfers energy through a seriestest the characteristics of simple machinesice cream. Then they will make and energy transfer mechanisms.
    test the qualities of glue. Finally, students will clean up an oil spill.
    2 Energy Conservation SystemsIn a series of activities studentsStudents will explore, document, and learn about [[home#|renewable]] and nonrenewableenergy, energy sources as they buildconservation, and experiment with models representing hydro, wind, geothermal, fossil fuel, solar, biomass,potential and nuclear [[home#|power generation]]. Students learn through [[home#|application]] the economic issues of scarcity of resources and the societal concerns associated withkinetic energy usageby designing, building, and waste products. Of particular interest will betesting a project build of a maglev transportation system.
    mable roller coaster.
    3 Prototype Fabrication – Using the knowledge gained from previous lessons studentsApplied Physics - Students will design, draw, fabricate,identify simple machines and assemble actual models ofdetermine their appropriate use and mechanical advantage. Students will then learn about systems and subsystems and have the following projects:opportunity to create a paper roller coaster,Rube Goldberg device, Air Dragster, and (hopefully) a [[home#|compressed air]] dragster. K-Nex Amusement Park Ride.
    Grading Policy
    Grades will be determined by participation in daily class work, activities, and occasional homework assignments, but most of the grade will be based on demonstrated mastery of the subject on daily classwork assessments. A wide variety of extra credit and enrichment activities are available giving students ample opportunities to [[home#|improve]] grades reduced by absence/illness or merely to pursue additional optional enrichment. Homework will be assigned 1-2 times a week and due dates will be indicated on the assignment. Late work may be subject to a 15% reduction in possible points and will not be accepted within one week of progress report/report card cut-off dates.
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