Enthalpy of Combustion of Alcohols

GCSE Science

Chemistry Coursework

Investigation

Procedure

1. Put 150³ of cold water in an aluminium calorimeter and record its temperature.

2. Support the calorimeter over a spirit burner containing the ethanol you are going to burn.

Arrange a suitable draft exclusion system to reduce heat loss.

3. Weigh the burner and Alcohol.

4. Replace the burner under the calorimeter and light the wick.

5. Stir the water with a thermometer.

6. When the water temperature has risen by between 15 and 20ºC extinguish the burner but continue to stir it until the temperature stops rising.

Record the highest temperature reached.

Reweigh the burner to find the mass of the alcohol that has been burned.
Repeat the experiment at least once more.
Now repeat the whole experiment 2 times but you have to use Methanol the first time and Butanol the second time instead of Ethanol.

Aim: The aim for this experiment is to find the Enthalpy of combustion of 3 different alcohols Ethanol, Methanol and Butanol by doing that I’m going to prove my theory.

How I will collect valid results in my planned experiment

I am planning was to do the experiment I will be very carfully in following the procedure I always will be wearing impervious clothing.I will be tryingto keep the wind as low as possible by clothing the windows .When I will be measuring the mass of water I will be using a measuring zylinder so I could mearure the mass of water very precily and I weighed it aswell.On the thermometers that we used I could measure up to 0.0 .

When I will weigh the burner containing the Alcohol in it I will weigh it as close as our weighing machine could measure it.I will be also very carefull about the measurement I checked every reading 2 x.