The lesson here is a good one and it applies to all your favorite demonstrations—they make terrific inquiry labs for your students!
This video is part of the Flinn Scientific Best Practices for Teaching Chemistry Video Series, a collection of over 125 hours of free professional development training for chemistry teachers –http://elearning.flinnsci.com
ATTENTION: This demonstration is intended for and should only be performed by certified science instructors in a safe laboratory/classroom setting.