Thermodynamics: Fusion
Determine the amount of thermal energy needed to change a specific quantity of ice (one gram) into water at a specific temperature (0°C). This amount of thermal energy is called the Latent Heat of Fusion of water.
A clear graph of temperature vs time makes it easier for your students to pick out the final equilibrium value.
Lab Summary
When ice melts into water, it absorbs thermal energy from its surroundings, but does not change temperature. The absorbed energy enables water molecules in the crystalline form of ice to break free of the bonds that hold them together.
The phase change from solid to liquid involves a transfer of thermal energy into the substance, but doesn't involve a temperature change for the substance.
Theory
The Latent Heat of Fusion of water is the amount of thermal energy needed to change one gram of ice into water at a specific temperature (O° C). Using a surplus of water and subtracting the energy used in the temperature change, the heat of fusion is calculated using the temperature probe to measure initial and final temperatures.
Downloads
- Download Free Lab (PDF, 260 KB) (258 KB, .pdf)
(student version)
Method
Use a Fast-Response Temperature Probe to measure the change in temperature of a known mass of water as ice changes from solid to liquid in the water. Calculate the latent heat of fusion of the water.
Here's What You Need
U.S. Educator prices shown.
Probeware
PASPORT Fast Response Temperature Probe (3 pack) (PS-2135) - $29
Allows students to see changes in temperature they could never see before. For use with PASPORT and ScienceWorkshop Interfaces.
Xplorer GLX (PS-2002) - $349
The Xplorer GLX is a data collection, graphing, and analysis tool designed for science students and educators.
Other Products
Basic Calorimetry Set (TD-8557A) - $129
Students can determine the specific heat of a substance, the latent heats of vaporization, and fusion of water.
Ohaus Triple-Beam Balance (without Tare) (SE-8723) - $147
This Ohaus triple-beam mechanical balance (without tare) is accurate and easy to use. This balance has been a standard weighing instrument in student laboratories for decades.
Other Materials
- Towel
- Water, about 15 degrees warmer than room temperature, 1 L
- Ice, crushed, 0.5 L
Lab Manual
This activity is included in Physics with the Xplorer GLX (PS-2826), complete with Teacher Information pages, student instructions and handouts, and sample data for a total of 35 probeware-based labs. For your convenience, we offer bundles which provide the probeware necessary for the activities in the manual. For more information on these resources and bundles, click here.
