To do this you must conduct experiments to determine which chemical system can produce a temperature drop of 10 C and its cost.

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1 NGSS Performance Task-Engineering / Argumentative Writing Student Directions: Your assignment: Alvarado has received a request from Dr. Michael Neeki, an emergency medicine specialist at Arrowhead Regional Medical Center, asking for help in designing a new cold pack. Your team is responsible for designing, testing, and bringing to market a new cold pack. To do this you must conduct experiments to determine which chemical system can produce a temperature drop of 10 C and its cost. Steps you will be following: Plan and conduct your experiment, you will do four parts over the next five days: DEC. 9: Obtain and evaluate information 1) Watch Video 1/Read Article: Doctor Profile 2) Video 2: The Chemistry of Cold Packs 3) Read the article How Do Instant Ice Packs Work? Close and critically read the article. 4) Participate in an academic class discussion. DEC 12: Plan and carry out an investigation 5) Dissect a cold pack, to see how it works. 6) Perform Experiments Analyze and Interpret Data DEC 13: Construct design solutions 7) In your group, note the materials you are using and collect data on the performance of your prototype. Then using what you ve learned improve your cold pack design, collect data, and show that the new design has better performance characteristics and/or uses less material. Using Mathematical and Computational Thinking 8) In your group, perform a Cost Analysis

2 DEC 14: Communicate information 9) Independently, create an 8 frame story board for an advertisement that convinces Dr. Neeki to order your cold pack. Be sure the advertisement describes how your cold pack works, how much it costs to make, and its advantages. You will also need to write the narration for your advertisement to go along with the story board. Group members:

3 Part 1, Day 1 Directions for beginning: Name/Period Watch a short video clip about Dr. Neeki and watch a video about how cold packs work. Take notes, because you will use the information in other parts of this assessment. You may refer back to any of the ideas, videos, or articles as often as you like while you are taking notes during this part AND during other parts of the assessment. Your notes will become the basis for writing your advertisement. Video 1: Doctor Profile of Dr. Michael Neeki Notes for Part 1, Day 1 Video 1: (Read Article) Dr. Neeki facts: Video 2: The Chemistry of Cold Packs When watching the video, be sure to focus on: How are temperature and motion related? What happens to the motion of particles when the temperature decreases?

4 In what way are endothermic reactions unusual? Article #1 How Do Instant Ice Packs Work? By Contributing Writer for ehow ( Overview of Instant Ice Packs A traditional ice pack is a plastic bag filled with frozen gel that is capable of maintaining extremely low temperatures for an extended period of time. Unlike traditional ice packs, instant ice packs do not need to be stored in a freezer before use and can freeze instantly through a chemical reaction. Instant ice packs are used therapeutically and are useful in emergency situations since they can be transported at room temperature. Many people also use instant ice packs in coolers to preserve meat, dairy products and other types of food. How Instant Ice Packs Work Instant ice packs use an endothermic reaction between water and ammonium nitrate to achieve cool temperatures rapidly. An endothermic reaction occurs when two separate compounds interact to absorb energy in the form of heat. Before it is used, an instant ice pack contains both water and ammonium nitrate in separate containers. When these container walls are broken, the water and ammonium nitrate mix, setting off an endothermic reaction and causing the water to freeze. The freezing of the water prevents all of the ammonium nitrate from instantaneously mixing with the water. As the ice melts, the water mixes with additional ammonium nitrate, causing additional endothermic reactions and forcing the melted ice to re-freeze. This process allows instant ice packs to remain frozen and maintain extremely low temperatures for an extended period despite being stored or

5 used at room temperature. Uses for Instant Ice Packs Instant ice packs are extremely useful for preserving food, particularly in situations where it is not possible to refrigerate food for long periods. Unlike pure ice, the water from instant ice packs cannot mix with food after use. Instant ice packs are also significantly more powerful that pure ice: four ice packs, when stored with food in a cooler, provide the same chilling power as 10 to 20 pounds of ice. Instant ice packs are also used extensively by medical professionals in both emergency and non-emergency situations. Cold temperatures cause muscles to numb and constrict, preventing the muscle from being overworked and allowing it to heal. Instant ice packs are smaller and much easier to transport than pure ice, making ice packs a favorite tool of physical therapists. Notes for Part 2, Day 1 Academic Discussion Questions: What advantages do instant ice packs have over traditional ice packs? How can the instant ice packs stay cold for so long? How might Dr. Neeki use these ice packs?

6 Part 2, Day 2 Dissect a commercial cold pack: What is inside a commercial cold pack? First, read the list of ingredients. What ingredients are listed? Also, read the directions for use. What are you supposed to do in order to use this product? To inspect what is inside, we can cut it open (carefully). Before opening the outer bag, gently explore the bag to feel what is inside. If there appears to be a liquid inside, when you cut the bag open, you do not want to spill the liquid; you want to collect the liquid in another container. How can you do this? Now, carefully cut the bag open to discover what is inside. What was inside? To use this product, you need to combine the chemicals that were in separate containers. You expect the temperature to drop if you combine these chemicals, so use a thermometer to determine the temperature of the liquid/solid before you start. Beginning temperature: Make a prediction: if you combine them now, what happens? Be sure to use a thermometer to measure the change in temperature. How cold did the mixture get? How much did the temperature change?

7 Part 2, Day 2-3 Directions: Today, you will be working in pairs. With your partner, combine the chemicals provided by your teacher to explore exothermic and endothermic changes. The goal of this activity is to find an endothermic process you can use to design a cold pack that the least amount of material. You will know that you are successful when you can decrease the temperature 10 C using the smallest amount of material. Academic Discussion Question: 1. Before you begin the experiments, can you predict how the temperature will change by looking at the materials? Using the vocabulary from Part 1, write a hypothesis for what you think will happen in each experiment. 2. Record the temperature of the room C. This is the initial temperature of all of the chemicals you will use. 3. To begin, you will need to explore what happens when the solid and liquid are mixed together in a cup. Use 25 ml of the liquid and 1 teaspoon of the powder. Record which chemicals are used, the final temperature, and your observations in the table below. Then calculate the temperature change and enter that into the table below. Liquid Powder Final Temperature Observations Temperature Change #1 #2 #3 #4

8 4. Based on the data we took, our group has decided to use as the liquid and as the powder because 5. Decide how much liquid you will use. Our group has decided to use ml of liquid because. 6. Decide how grams of powder you will use. Our group has decided to use grams of powder because. 7. Combine your chemicals in a cup. The final temperature was C and the temperature change was C. 8. Did your mixture change by 10 C? If not, based on the data above, how will you change the amounts of liquid and/or powder to achieve a change in temperature of 10 C? 9. Record below data from your experiments. Liquid used Powder used Final Temperature Temperature Change ml used Grams used #1 #2 #3 #4 10. In our experiment that came closest to decreasing the temperature by 10 C, we used ml of and grams of.

9 11. Now that you have perfected your recipe for making a cold pack, actually make a cold pack by using a small zippered bag inside of a larger zippered bag. Thinking back to the dissection of the commercial cold pack, was the liquid in the little, inner bag or the outer, larger bag? 12. Draw a model of your finished cold pack in the box below. Be sure to label its parts. 13. Now you will need to make sure that your cold pack actually works. Use the thermometer to determine the starting temperature of the cold pack. Now start the reaction in the cold pack by breaking the inner bag (without breaking the outer bag!) while monitoring the temperature. Initial Temperature ( C): Final Temperature ( C): Temperature Change ( C): 14. Determine the cost of the materials used to produce your cold pack. First write the ingredients and the amounts your group used to make your cold pack. Look up the cost per unit on the following page and include the cost per unit of your materials in your table.

10 Cold Pack Ingredients Cost Table Ingredient Amount Used (include unit) Cost Per Unit Total Cost Per Ingredient 1 X = 2 X = 3 Small bag X = 4 Larger bag 1 bag X 2.00 cents/bag = 2.00 cents Total Cost of Materials for Each Cold Pack 15. To find the total cost per ingredient, you need to multiply the amount of units (for example, 100 gram) by the cost per unit (for example 0.25 cents/gram). For the example quantities, the total cost per ingredient is: 100 gram x 0.25 cents/gram = 25 cents. As an example, the cost of the larger bag has been completed for you. 16. To find the total cost of materials to create each cold pack, add together the total cost for each ingredient. Item Number Item Cost Per Unit 1 Baking Powder 0.36 cents/gram 2 Calcium chloride 0.35 cents/gram 3 Epsom Salts 0.24 cents/gram 4 Hydrogen Peroxide 20% 0.29 cents/ml 5 Hydrogen Peroxide 3% 0.22 cents/ml 6 Hydrogen Peroxide 40% 0.71 cents/ml 7 Larger Zippered Bag 2.00 cents/bag 8 Small Zippered Bag 0.72 cents/bag 9 Sodium carbonate 0.13 cents/gram 10 Water 0.02 cents/ml 11 Yeast 0.54 cents/gram

11 Part 3 Directions: Over the past few days, you have been designing and building a cold pack and determining how much the materials cost to make your cold pack. Today, you will communicate your findings by creating an 8 frame story board of the advertisement that convinces Dr. Neeki to purchase your cold packs. You will also need to write the script for the narrator of your 30 second advertisement. You will have time to review your notes, your data, and plans, draft, and revise your story board and script for your advertisement. You must complete this section on your own. Watch the Video: Ice Packs and Hot Packs That Are Designed For Clinical Use. This video is an example of an advertisement for a similar product. As you watch the video, be sure to note the choice of voice, the persuasive argument, and highlighting of advantages of their product. Note that this video is 2 minutes and 25 seconds long much longer that your advertisement will be. Your Writing Assignment: Dr. Michael Neeki is looking to you for a new cold pack that can be used in his practice as an emergency physician. The storyboard provided on the next page has 8 frames. Think about what 6-8 scenes you want to include in your advertisement. Draw the scenes of your advertisement in the storyboard frames. (Stick figures are OK for people if the viewer can tell what they are and what they are doing. However, your storyboard must still be neat.) To complete your advertisement, you need to provide the narrator with a script (for the voice over ). Based upon your analysis and discussion, write a script that sells your cold pack to Dr. Neeki. Be sure to include the name of your product, the details of your product design, and the cost of materials needed to produce your product. Be sure to base the information in your advertisement on data obtained for this project. Remember that the narration portion of your advertisement must last for 30 seconds while spoken. How your advertisement will be scored: How your advertisement will be scored: 1. Coherence do the scenes in the storyboard follow the order in which they are mentioned in the script 2. Presentation of relevant evidence how well you provide support and elaboration for your claim with specific information from the videos, article, and experiments, and how well you stay on topic throughout the advertisement 3. Organization how well your ideas logically flow from your statement of focus, to supporting ideas, to concluding statement(s) 4. Language, tone, purpose, audience the appropriateness of your language and tone for your purpose and audience 5. Content the accuracy and relevance of the information you use Now, begin work on your advertisement. Manage your time carefully so that you have time to: Plan, write, Revise and Edit before writing your final copy

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