In this Activity, students test two chemical deicers, rock salt (sodium chloride) and calcium chloride, to determine which melts ice better and whether it is worth the extra cost to buy a more expensive deicer. They perform three tests comparing the two deicers, predict which will be more effective at melting through a thin disk of ice, and then test their prediction.
In this Activity, students make their own toothpaste and use various tests to compare its properties with those of commercial toothpaste. This includes testing its ability to remove stains from the dyed shells of hard-boiled eggs. The Activity allows students to discover more about a cleaning product they use every day.