Observing Latent Heat With a Portable Hand Warmer

Students conduct a series of investigation on latent heat of fusion. In this chemistry lesson, students explain how thermal storage systems work. They draw and interpret graphs.

How does heat move from one item to another, even when the items are in different states of matter? Pupils experiment with adding washers to hot water and adding hot washers to room temperature water to observe the heat transfer. 

Step-by-step instructions are given for two hands-on activities. Young scientists cut out a paper spiral and hold it over a hot plate to demonstrate convection, and they place a small piece of wax on the end of a metal rod opposite the...

Learn about conduction, convection, and radiation with an illustrative presentation. It includes slides about atmospheric movement and how it affects the climate, solar radiation, and how latent heat can form storms. 

Where does the heat come from in hand warmers? Learn about enthalpy, the change in energy in a system, to see that when chemical bonds are broken or formed, energy moves into and out of a system because of chemical reactions. 

When the chemists who designed hand warmers were working, they had to consider how much heat they could give off to keep people warm  — and not burn anyone in the process. How is this heat given off in a chemical reaction measured?...

What happens inside a melting solid? Prospective physical chemists observe a solid-to-liquid phase change at the molecular level using an inspired interactive. Pupils add heat to a close system, then monitor changes in kinetic and...

There's more to melting than meets the eye! Junior physical chemists investigate the differences between specific and latent heats as a substance undergoes a phase change. Users remove heat from the system and observe changes in kinetic...

How can heat power an engine? Scholars observe a heat engine working and control variables to determine the most efficient setup. They change the amount of heat input as well as the stroke length. Energy efficiency numbers prove the...

For this planaria lab, 10th graders observe a live planarian and make observations about it's movements, it's handedness, it's size and the effects of light on the planarian. They design an experiment to observe the effects of light and...