In this Activity, students make a chemical clock using chemicals found in the supermarket: vitamin C tablets, tincture of iodine (2%), hydrogen peroxide (3%), and liquid laundry starch. They investigate what happens to the speed of the clock when the reactant solutions are made more or less dilute.
In this Activity, students investigate a classic chemistry demonstration that uses the phenomenon of freezing-point depression to lift an ice cube out of a glass of water with a thread. They first test how adding salt, pepper, cream, and sugar to cold water affects the temperature.
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.