TEACH PHYSICAL SCIENCE?
1. Conservation of Mass: Covering the law of conservation of mass after introducing physical vs chemical changes? Students can see how the mass of the glow stick shouldn’t change before and after a chemical reaction. While electronic scales work best for this, triple beam balances will still work. (If you want to see more conservation of mass ideas, check out this blog post).
2. Star luminosity: We know that the hotter a star is, the brighter it will be. Before introducing HR diagrams, pop a glow stick into a beaker of hot water, and another glow stick into a beaker of cold water. Students will see that the glow stick is much brighter in the hot water. HR diagrams can be a bit overwhelming at first, so this is a fun and easy way to introduce the concept.
3. Rate of reactions: When we talk about enzymes, we discuss how they only work in a specific range of temperature and pH or they denature. How does heat impact the rate of reactions in our bodies? For this lab I gave students 3 glow sticks and they had to figure out how to test the effect of temperature on the rate of the chemical reaction. The only thing that tripped them up when designing their experiment was how they would measure the dependent variable. (Many groups said they would time how long the glow stick glowed… well I didn’t want to wait around for 24 hours!) So we decided we would only crack the center of the glow stick (not the entire thing) and time how long it took for the reaction to spread.