Chemical Thermodynamics : Heat of Combustion

Investigate how much heat is transferred from a burning candle to a known mass of water. From the heat transfer, determine the heat of combustion of paraffin.

Lab Summary:

In this activity, students will use the a temperature sensor to measure the heat transferred from a burning candle to the water in a metal can. From the data they will calculate the energy per gram of wax burned and the molar heat of combustion for the wax.

Download Free Lab  (PDF, 464 KB)

(student version)

Method:

Use the Temperature Sensor to measure the heat transferred from a burning candle to the water in a metal can. Calculate the energy per gram of the wax burned and the molar heat of combustion for the wax.

Here's What You Need:

Probeware

• PASPORT Temperature Sensor (PS-2125)
• Xplorer GLX Graphing Datalogger (PS-2002)
  (or alternate PASPORT interface -- see other options)

Other Materials

• Small Tripod Base & Rod (SE-9451)
• Buret Clamp (SE-9446)
• Balance (SE-8756A)
• Aluminum foil
• Can, metal, small
• Candle, paraffin, small
• Graduated cylinder, 100 mL
• Matches
• Ring, support, with rod support
• Stirring rod
• Water, chilled

Lab Manual:

This activity is included in Explorations in Chemistry (PS-2808), complete with Teacher Information pages, student instructions and handouts, and sample data for a total of 25 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.