UNIT 2:Course Activity: Building a Device that Uses Energy from Chemical Reactions task 3
Part A
Identify the problem that the cold pack must address.
Part B
Criteria are the specific goals of the design. List at least two criteria for the design based on the question, What do you want it to do? Keep in mind the design of the cup and what you learned from observing the endothermic chemical reaction.
Part C
Constraints are the limits that we place on a design. Time, materials, or money may be in short supply. Some designs may also be limited by how the product gets used. List at least one constraint on the cold pack design.
Part D
Question
Brainstorm ideas about how to separate the three reactants in the cold pack. Draw your ideas and use text boxes to explain them. Recall the materials list and the layout of your cup from task 2 to help you.
Part E
Question
Create drawings of two fully worked-out ideas for mixing the reactants in the cold pack. Use text boxes to explain your ideas.
Part F
What are the pros and cons of each idea that you explored in part E? How do the ideas compare?
Part G
Select one of your cold pack mixing mechanisms, and use items from the materials list to build a prototype. The prototype doesn’t have to be true to size, but the mechanism for combining the reactants must work. You’ll test the prototype later, so make sure to line the compartment that holds the water with a plastic bag. Describe what you did.
Part H
Test your prototype. Pour ½ cup of water into the compartment that holds the water. Add 2 teaspoons of baking soda to each of the compartments that hold the solid reactants. Test your mechanism for combining the reactants. Did the prototype work? Record the results of your test here. (Note that a chemical reaction will not take place because citric acid isn’t used.)
Part I
Question
Based on the test of your prototype, refine your design and make a final drawing. Use text boxes to label the final design and to note changes that you made.
pls If you got for task 1,2,3 all right send a screen shot PLS