The aim of this investigation is to determine which of the two derivatives of ethanol releases more energy, Bioethanol or Industrial Ethanol.
The main compound in both alcohols has the same chemical formulae C2H5OH, and the other compounds are unknown therefore the Energy output cannot be calculated exactly by using standard bond enthalpies. However, as the main compound is known and the same for both ethanol’s the energy output should be very similar. Therefore the difference in energy output only depends on the compounds which are blended to the alcohols.
– Metal can x2
– Draught shield x4
– Safety spectacles
– Heat-resistant mat
– Insulation card
– 100cm3 measuring cylinder x2
– Spirit burner
– Clamp stand
– E100 Bioethanol
– Industrial Ethanol
The idea to do the experiment the way described is due to knowledge from past experiments and the IB textbook.
Follow these steps 10 times, five times for each alcohol.
Step 1: Measure 50cm3 of alcohol in a measuring cylinder
Step 2: Weigh and record the empty spirit burner
Step 3: Fill the 50cm3 of alcohol in the spirit burner
Step 4: Weigh and record the filled spirit burner
Step 5: Measure 100cm3 of Water in a measuring cylinder
Step 6: Fill the water into the metal can
Step 7: Set up the Apparatus as displayed (1 draught shield in each direction, south, north, west and east, forming a box around the apparatus; assure there are 2cm of space between the bottom of the metal can and the cotton wick)
Step 7: Record the initial temperature of water
Step 8: Light the cotton wick of the spirit burner
Step 9: Record the temperature every 15 seconds until the cotton wick loses its flame
Step 10: Weigh the spirit burner with the remaining alcohol to calculate how many grams of alcohol have been used
– Temperature: Temperature of Water will be measured before every experiment.
The whole experiment takes place at room temperature.
– Volume of Water: 100cm3
– Mass of alcohol: 50cm3 filled in spirit burner. The mass will be measured before and after the experiment to figure how much has been used.
– Time: record every 15 seconds
– Concentration of alcohol: 1M
– Surface area of metal can which flame is heating up: same cans will be used and positioned at same place above the cotton wick to keep this constant.
– Length of cotton wick: 0.5cm
– Distance from cotton wick to bottom of metal can: 2cm
– Industrial Ethanol: Highly flammable. Therefore wear gloves and safety spectacles
– Bioethanol: Highly flammable. Therefore wear gloves and safety spectacles
Chemistry HL – Plan of Investigation