What is the best Fuel?

• Methanol
• Ethanol
• Propanol and
• Butanol

Once I had done this experiment three times for each different type of fuel, I got an average.  This average was more precise than getting just one result for each of different type of fuel.

To make sure that this experiment was a fair test, I will make sure that the bottom of the copper can is always the same distance away from the wick of the fuel can (130 millimetres).  I will also be shielding the experiment each time using four heat proof mats to make sure that the heat is in one place and isn't blown about when people walk past.   Another way of keeping it a fair test is by waiting for the copper can to cool down between each experiment and by getting fresh tap water each time.  Also, I will be making sure that each fuel only burns for five minutes exactly and leaving the thermometer in the water until it has risen fully to its highest temperature before recording anything down.

Diagram of the apparatus

On next page

  Some safety procedures that you should follow to ensure your safety are:

• Always wear safety goggles
• Wash your hands before lighting anything if you spill any fuel on you hands
• Do the experiment on a clean and clear work surface
• Wait for the copper can to cool down before picking it up because it could be hot

I predict that Butanol will be the best fuel, because when Butanol is burnt, there are a lot more bonds being formed than are being broken.  Heat is always given out when bonds are formed.

E.g. Butanol

                  C4H9OH + 6O2 → 4CO2 + 5H2O

This is an exothermic reaction because an exothermic reaction has more bonds being formed than broken during the reaction as well.

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Average Tables

Conclusion

From my graph I can see that the best fuel is Butanol because it lost the least weight and gave out the most heat.   I can also see from this graph that when the weight loss grows, the temperature rise falls and when the weight loss gets smaller, the temperature rise increases.

Before I did the experiment, I predicted that Butanol would be the best fuel.  This prediction was correct.  I can tell this because Butanol gave off the most heat when the bonds were being formed.  Lots of bonds were being made during the experiment as Carbon Dioxide and water was being formed.  This releases energy.

                C4H9OH + 6O2 → 4CO2 + 5H2O

Evaluation

My results were very accurate because they all follow the trend that the weight loss growing would make the temperature rise fall.  My results also fit into a straight-line graph and I have one odd result for the temperature I measured before.  It was higher at 27.3ºC than the others at 21.9ºC.  Luckily this did not affect my averages on the graph I made.  This could have happened because I did not let the copper can cool down properly before I repeated the experiment.

If I did the experiment again I would be 100% accurate in the space between the copper can and the fuel pot.  I would also make sure I left the copper can to cool down properly before repeating the experiment again.