Introduction
In this investigation we are trying to find out which out four alcohols gives off the most energy when burnt. We are using Methanol, Ethanol, Propanol and Butanol. We will investigate this by burning the alcohol under a tin can of water after weighing it an when the water gets to a certain temperature we will put the alcohol out and weigh it again. Using this and the bond energy values for the equation of the burning of each individual alcohol we will be able to discover how much energy in Kj/mol each alcohol gives and therefore which one contains the most energy.
. Safety
* Burning alcohols, flammable - always wear goggles
* Tin cans conduct heat - so they get hot
* Thermometer filled with mercury - poisonous
2. Method
a. Set up equipment as above.
b. Weigh alcohol and record.
c. Place underneath tin can, which will be filled with 200ml of water.
d. Record temperature of water watching carefully until it reaches 40oC.
e. Extinguish flame.
f. Weigh alcohol and record.
g. After each experiment I will empty out the water from the can and get a fresh amount from the tap so that the water always starts off cold.
h. Also I will make sure that the alcohol is always the same distance from the can for every experiment.
i. I will need to do this twice for each of the alcohols.
Continue this method with other alcohols.
3. Prediction
Because Butanol has the most bonds, I believe it must use the most energy.
Bond Energy (Kj/mol)
C - H 413
O - H 464
C - O 358
O - O 498.3
C - O 805
C - C 347
H - H 436
Using the bond energy values (shown above) I will try to work out how much energy the alcohols will give off. For example: CH3OH is the formula for methanol, and it contains 3 C-H bonds, 1 C-O bond and 1 O-H bond. Using the bond energy values from the above table I can work out how much energy is needed to break the bonds of CH3OH by adding all the values together. I do this to all the formulae I have in that chain, I can work out the energy needed to break all the bonds. I work this out by adding all the bond energy values on the left side of the arrow together and adding all the bond energy values together on the right hand side and taking the total from the right away from the total from the left. I am doing this for each of the alcohols so that I can compare them with the results.
In this investigation we are trying to find out which out four alcohols gives off the most energy when burnt. We are using Methanol, Ethanol, Propanol and Butanol. We will investigate this by burning the alcohol under a tin can of water after weighing it an when the water gets to a certain temperature we will put the alcohol out and weigh it again. Using this and the bond energy values for the equation of the burning of each individual alcohol we will be able to discover how much energy in Kj/mol each alcohol gives and therefore which one contains the most energy.
. Safety
* Burning alcohols, flammable - always wear goggles
* Tin cans conduct heat - so they get hot
* Thermometer filled with mercury - poisonous
2. Method
a. Set up equipment as above.
b. Weigh alcohol and record.
c. Place underneath tin can, which will be filled with 200ml of water.
d. Record temperature of water watching carefully until it reaches 40oC.
e. Extinguish flame.
f. Weigh alcohol and record.
g. After each experiment I will empty out the water from the can and get a fresh amount from the tap so that the water always starts off cold.
h. Also I will make sure that the alcohol is always the same distance from the can for every experiment.
i. I will need to do this twice for each of the alcohols.
Continue this method with other alcohols.
3. Prediction
Because Butanol has the most bonds, I believe it must use the most energy.
Bond Energy (Kj/mol)
C - H 413
O - H 464
C - O 358
O - O 498.3
C - O 805
C - C 347
H - H 436
Using the bond energy values (shown above) I will try to work out how much energy the alcohols will give off. For example: CH3OH is the formula for methanol, and it contains 3 C-H bonds, 1 C-O bond and 1 O-H bond. Using the bond energy values from the above table I can work out how much energy is needed to break the bonds of CH3OH by adding all the values together. I do this to all the formulae I have in that chain, I can work out the energy needed to break all the bonds. I work this out by adding all the bond energy values on the left side of the arrow together and adding all the bond energy values together on the right hand side and taking the total from the right away from the total from the left. I am doing this for each of the alcohols so that I can compare them with the results.
