• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9

Alcohol Combustion Investigation

Extracts from this document...


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. 1. 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. ...read more.


I decided to use 200ml of water because I though if I used any more than it would take up a lot more energy from the alcohol and time for the practical. * Same equipment set-up because if I didn't the tin could be closer to the flame or further away which would either give the water more or less energy. * Do not let the water boil/let off steam because if I let it boil/let off steam then the volume of water would change which in turn would make the results be different because the alcohol would be heating different volumes of water. * Stir the water so that it is heated evenly otherwise energy would only reach parts of the water and depending on where you placed your thermometer you could get different results. RESULTS Weight Before (g) Weight after (g) Weight loss (g) Average weight loss (g) Temp. Before (oC) Temp. After (oC) Change in temp. (oC) Methanol 155.89 183.64 2.25 2.21 22 40 18 Methanol 2 217.78 215.62 2.16 21 40 19 Ethanol 176.72 174.75 1.97 1.96 19 40 21 Ethanol 2 174.71 172.76 1.95 20 40 20 Propanol 200.19 199.18 1.01 1.21 25 40 18 Propanol 2 199.16 197.75 1.41 23 40 17 Butanol 170.53 169.14 1.39 1.28 20 40 20 Butanol 2 169.13 167.96 1.17 20 40 20 Now I am going to find the average if the energy released by using this formula: - Energy released = mass of water (ml) ? temp rise ? specific heat capacity of water (4.18Kj) Temp Rise (oC) ...read more.


An alternative method to the one I used would be to use a bomb calorimeter. Bomb calorimeters are more complex than your simple calorimeter. It consists of two main parts, the bomb and an outer shell filled with water and a thermometer. The bomb, or the inner compartment, is where the chemical reaction occurs. If the reaction is endothermic, the bomb will absorb heat from the water, causing the water's temperature to drop, which is detected by the thermometer. In an exothermic reaction, heat is absorbed by the water, causing its temperature to increase. This is what bomb calorimeter looks like. This is a much better method as the reaction takes place within a chamber so that no heat is lost. Because no heat is lost it means that the results will be much closer to the prediction. Also, it will be easier to keep the surroundings the same because it is in a chamber so there won't be any change in environment because a window is open or something like that. There is also another method that is not the best one but is better than the one I did. It is set up like this: The calorimeter is designed to make sure that as much as possible energy is transferred to the water. It is done in two stages: Stage 1 A measured quantity of fuel is burned and the rise in temperature recorded. Stage 2 The heater is switched on and kept on until the water reaches the same temperature as it did with the burning of the fuel and the time it takes is recorded. ?? ?? ?? ?? 1 Steven Cowling The burning of Alcohols ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Organic Chemistry section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Organic Chemistry essays

  1. Investigating the Combustion of Alcohols

    This was not expected, so I had to weigh it on another set of scales, which provided me with a different recording. Due to this, other readings may have been manipulated and not very reliable.

  2. To determine which alcohol, out of ethanol and propanol, is the better fuel. By ...

    This can be used to find the specific heat capacity of water, which is 4.2 Jg-1K-1. Energy transfer is measured in joules and is calculated by the following equation: Energy ? = m x c x ?T joules Where m is the mass of water (kg), c is the specific

  1. The Heat of Combustion of alcohol.

    Method Collect and set up apparatus shown in the diagram: Measure out 100cm of water into the calorimeter. 100cm has the mass of 100g. Clamp the calorimeter into place so that it is just above the spirit burner. Take the initial temperature of the water.

  2. Molar Heat of Combustion of Alcohols

    Grams (g) we will use Grams to weigh the alcohol before and after burning. Real Results: Ethanol Test 1 Before After Difference Container Weight 92.44 91.71 0.73 Temp of Water 23 69 46 50*4.2*46=9660 9660/0.73=13233 13233*46 Heat transferred to the copper calorimeter by burning one mole of ethanol.

  1. Investigate the enthalpy change of different alcohol

    because human eyes are not accurate enough to detect readings less than 1 decimal place **- readings on the electronic balance is corrected to 2 decimal places so all the readings in the table are corrected to 2 decimal places Analysis From my results, I work out: -the mass of

  2. "Could Sainsbury's add value to their business by using an alternative fuel for their ...

    * Promote switch to Natural Gas * Van fleet livery * Carrier bags * Television ads 7.6 Evaluation: Due to the subjectivity involved in customer perception, it is difficult to predict exactly how any customer base will react to new marketing strategies.

  1. An investigation into the heat of combustion of alcohol's

    Diagram How I will make my experiment a fair test There is not really that much I can do to help make this experiment a fair test but I will; cool the copper calorimeter completely down by running it under cold water for a few minutes so that the water doesn't get warmed up by being in contact with it.

  2. GCSE Chemistry Revision Notes - everything!

    The general formula for alkenes is CnH2n. There cannot be an alkene with only one carbon atom as alkenes all have a carbon-carbon double bond. In alkenes the bonds are arranged symmetrically around the carbon. The bond angel is 120° and the bonds point to the corners of an equilateral triangle.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work