Gizmos : Student Exploration: Feel the Heat Lab 2020

Student Exploration: Feel the Heat Vocabulary: calorimeter, conductor, controlled experiment, dissolve, endothermic, exothermic, insulator, solute, solution, solvent, surroundings, system Prior Knowledge Questions (Do these BEFORE using the Gizmo.) Eduardo hurts his knee during a basketball game. The trainer applies a cold pack, which gets cold after being squeezed. The next day, Eduardo’s friend Beth is going sledding. Beth buys some hand warmers and puts them into her gloves. All morning, her hands stay toasty warm. 1. How do you think these devices work? I think that applying pressure causes the devices to be cold/warm. 2. Where do you think the “cold” and the heat comes from? I think it comes from molecules colliding. Gizmo Warm-up As you saw with the instant cold pack and the hand warmers, some reactions absorb energy while others release it. In the Feel the Heat Gizmo, you will explore these energy changes while making your own hot and cold packs. To begin, select the TEST POWDERS tab. Drag a bottle of NaC2H3O2 (sodium acetate) from the shelf. Using the sliders, decide how much water and powder to add. Note the beginning temperature, and then press Play () to see what happens. 1. Did the temperature go up or down? Up 2. Experiment with different powders until you find one that produces the opposite effect. What powder did you use? NH4NO3 When a