In this lab, students make notches in 2 different pennies and expose both pennies to acid. By measuring their changes in mass, students can collect data to determine the percentage of zinc in each penny.
I use this lab to instruct my students in proper lab technique, data collection, calculation of accuracy & precision, and to generate interest in chemical reactions and the history of the penny. It's a great cross-curricular activity! I require that my students demonstrate a certain level of accuracy to receive credit, which really motivates them to be careful in the lab and work their math correctly.
This product includes teacher instructions, procedures, a student lab sheet, and an answer key. They're in WORD format, so you can edit them!