Bomb Calorimeter Lab Mike Martin, Pete Strader, and Kevin Healy
Dec 24, 2015
Purpose
• To see if modifications to bomb calorimeters would increase efficiency• Part I: Testing the calorimeters thermal
qualities of insulation and speed of heating• Part II: Seeing if modifications gave a
closer estimate of a fuel’s heat capacity.
Thermal Testing
• Using a Bunsen Burner with a consistent flame, we tested how long it took for each calorimeter to reach 50° Celsius and how long before each began loosing heat over a period of 15 -20 minutes. • The Chart has been shortened to when the
most insulated began to loose heat.
Thermal Energy to Heat Water
Fuel Control Fiberglass Aluminum
Methanol 4.598 kJ/g 4.598 kJ/g 4.18 kJ/g
Butural 5.016 kJ/g 5.434 kJ/g 4.18 kJ/g
Heat of Combustion
Fuel Ideal/ Expected Control Fiberglass Aluminum Foil
Methanol 64.09 kJ/g 11.495 kJ/g 11.495 kJ/g 13.934 kJ/g
Butural 75.87 kJ/g 16.72 kJ/g 18.113 kJ/g 13.934 kJ/g
Materials
• Three aluminum cans • A roll of tinfoil• Fiberglass insulation • i-butanol • Methanol • Two stoppers with wicks • Match book or lighter
• 3 very large soup cans • Glass thermometer • 6 stands with rings
attached • Stop watch • Tap water • Scale
Conclusion • We found that tinfoil was the best insulator for methanol and
the fiberglass was the best insulator for i-buterol. However neither were close to the ideal target energy output for their respective fuels. This can be attributed to the lack of ideal conditions in which to conduct the experiment.
• We found that the insulated bombcalorimeters took longer to reach 50 degrees C than the control. The Fiberglass insulator took the longest to heat to 50 C.
• Finally we found that both the tinfoil and the fiberglass insulators retained the heat longer than the control. The fiberglass insulator however was much more efficient than the tinfoil insulator. This fits because it also took longer to heat up to 50 C.
Equations and Ideal Data• Heat absorbed by the water (calories) = Mass of water (grams)
x Temperature change (oC) x 1.00 cal/g oC
• i-Butanol: 75.87 KJ/g• Methanol: 64.09 KJ/g
Single Bonds kJ/mol
H—C 416
C—C 356
C—O 336
O--H 467