# Combustion of alcohols lab report

5/2/2010 6:11 PM

• Aim: To calculate the enthalpy changes during the combustion of a variety of alcohols and to compare the results by calculating equimolar quantities.
• Apparatus and Materials:
• Safety glasses
• 8 spirit burners containing different alcohols
• A copper calorimeter
• Clamp and stand
• Thermometer (1°C)
• Weighing balance (0.01g)
• Method:
1. Weigh calorimeter
2. Reweigh calorimeter containing water (80 cm^3)
3. Place thermometer in water and note initial temperature
4. Weigh spirit burner with its cap.
5. Place the spirit burner under calorimeter (About 5cm)
6. Light the burner, stir the water with the thermometer (occasionally) and observe the rise in temperature. When it has risen between about 8 to 10°C, put the flame out with the cap, and measure more precisely the maximum temperature reached.
7. Weigh the burner and cap as soon as possible.
8. Repeat the experiment with all the other spirit burners (including unmarked one), changing the water each time. You do not need to reweigh the empty calorimeter, but you need to reweigh it with the water in it.

Results:

Table of Results

Table of data

• Table to show energy differences between preceding alcohols

Data Processing

• Calculations
• Energy liberated for each alcohol (J)
• Formula: m.c.Δt
• Ethanol: 158.54 x 4.18 x (32-20) = 7952.37
• Propanol: 158.04 x 4.18 x (34-21) = 8587.89
• Butanol: 159.18 x 4.18 x (34-22) = 7984.47
• Pentanol: 159.32 x 4.18 x (33-21) = 7991.49
• Hexanol: 158.37 x 4.18 x (34-21) = 8605.83
• Heptanol: 158.03 x 4.18 x (35-20) = 9908.48
• Octanol: 159.54 x 4.18 x (39-22) = 11336.91
• Nonanol: 159.67 x ...