colligative properties

An After-Dinner Trick

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.

Meltdown Showdown! Which Deicer Works Best?

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.