IS II students collectively investigated how concentration affects the rate of a chemical reaction. Using acetone, HCl, iodine, and distilled water the students varied the acetone volume (5, 10, 20 mL) vs the water voume (25, 20, 10 mL) and kept the HCl and iodine at 10 mL. Results were spectacular. The students built a lab report from the ground up on Google Drive as we did the lab. Graphing will be done with Logger Pro.
We just finished with momentum and macroscopic collisions and this activity (two different size BBs in sealed petri dishes) is a nice bridge between those and microscopic collisions. At the end the students are able to better see how changing temperature (increase the shake frequency) and concentration (2nd petri dish has double the BBs) affects the number of collisions in a chemical reaction. Later this week we will look at an acetone-HCl-iodine clock reaction and how these two variables affect the rate of the reaction.