This is a several-day lab designed for an elementary chemistry unit. Kids collect data by observing, conducting a heat test and using three reagents. They then take their data and use them to determine what is in new mystery powders. This lab uses every-day products that can be purchased in grocery and drug stores. It's easy on the pocketbook, but really challenges and hones kids' thinking skills. I've used this lab as part of my elementary chemistry unit for many years with great success.