• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  6. 6
    6
  7. 7
    7
  8. 8
    8
  9. 9
    9
  10. 10
    10
  11. 11
    11
  12. 12
    12
  13. 13
    13
  14. 14
    14
  15. 15
    15
  16. 16
    16
  17. 17
    17
  18. 18
    18
  19. 19
    19
  20. 20
    20
  21. 21
    21
  22. 22
    22
  23. 23
    23

Enthalpy of Combustion of Alcohols

Extracts from this document...

Introduction

Chemistry Coursework Investigation Enthalpy of Combustion of Alcohols Procedure 1. Put 150� 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 20�C extinguish the burner but continue to stir it until the temperature stops rising. Record the highest temperature reached. 7. Reweigh the burner to find the mass of the alcohol that has been burned. 8. Repeat the experiment at least once more. 9. 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 ...read more.

Middle

kj Energy Released per mole of Methanol burned 108829.1125 kj 112423.924 kj 121191.532 kj Results for Butanol Mass of Beaker 78.71g 1 2 3 Mass of water 150.28 g 150.89 g 148.2 g Initial temp of water 22.60 C 22.90 C 22.5 C Final temp of water 43.1 C 43.4 C 43.7 C Temperature rise 20.5 C 20.5 C 21.2 C Mass of burner initially 183.59 g 181.60 g 179.38 g Mass of burner finally 181.60 g 179.38 g 176.84 g Mass of Butanol burned 1.99 g 2.22 g 2.54 g RFM of Butanol 74 74 74 Moles of Butanol burned 0.02689 g 0.03 g 0.0343 g Energy released 12939.108 kj 12991.629 kj 13195.728 kj Energy Released per mole of Butanol burned 48118.661 kj 433.054 kj 384715.102 kj Difficult Calculations about alcohols Example Butanol Moles of Butanol burned=Mass of Butanol burned RFM of Butanol Energy released= m x c x?T (Mass of water x 4.2 x Temperature rise) Energy released per Energy released Mole of Butanol burned= Moles of Butanol burned Diagram of the Experiment Equipment to use -200ml aluminium calorimeter -500ml plastic calorimeter -Thermometer -Fuel-burner -Triangle-stand -Heatproof mat -Fire Resistant underground -Safety goggles -impervious clothing -gloves -Respiratory protection May be required Materials to use -100ml of Ethanol -100ml ...read more.

Conclusion

Structural Formula: Bond Braking Bond Forming Bond Number Energy Bond Number Energy C-C C-H C-O O-H C=O O=O C-C C-H C-O O-H C=O O=O Total energy used= Total Energy released= Overall energy change= Enthalpy of Combustion of Butanol Balanced Equation 2C4H7OH + 12O2-----------8C02 + 10H2O Structural Formula: Bond Braking Bond Forming Bond Number Energy Bond Number Energy C-C C-H C-O O-H C=O O=O C-C C-H C-O O-H C=O O=O Total energy used= Total Energy released= Overall energy change= Evaluation I believe that the procedure which I used was very good and I obtained very good evidence with my simple procedure.I had 1 anomili in my second reading for Butanol but I did a third reading I think my results were relieable because I didn�t have many anomalis but I believe that this experiment was not as accurately as it could have been because: 1:Because of the Heat loss on the top and side on the beaker. 2:Incomplete Combustion 3:There is heat which never arrives at the beaker because of winds. 4:That not all the water was the same temperature. I could have improved my results by isolating the the beaker from the top and the sides I could have build a wall where no wind would have gone through. ...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

    - 1136.1 kJmol-1 Table showing a summary for the results obtained and their accuracy (%) Alcohol Enthalpy Change of Combustion kJmol-1 Accuracy Methanol -254.0 38.6% Ethanol -381.3 29.9% Propan-1-ol -543.1 28.7% Butan-1-ol N/A N/A Pentan-1-ol -1136.1 36.3% NB: The percentage accuracy was found using the following equation: ANALYSIS Summary Table

  2. Comparing the enthalpy changes of combustion of different alcohols.

    Safety In order to keep my experiment safe I will do the following; * Wear safety goggles and protective clothing (lab coat). * Keep all of the alcohols away from naked flames as they are all extremely flammable. * Work in a safe environment - free from clutter.

  1. Experiment to Measure the Heat of Combustion of Butanol.

    This was the heat not being directly on the water due to a draft causing the flame to move away from the apparatus occasionally. Reliability of Results- The results recorded were as accurate as possible, but it is feasible that they could have been misread or inexact.

  2. Investigate the enthalpy change of different alcohol

    for the 1st trial: Energy transferred = 15.6C x 200g x 4.17 J/C/g = 13101.4J Butan-1-ol Change in temperature (c) Change in weight of the spirit burner (g) Energy transferred (J) 1st trial 16.75 -0.66 13969.5 2nd trial 16.75 -0.7 13969.5 Average 16.75 -0.68 13969.5 E.g.

  1. 'Enthalpy of Combustion'.

    All long hair and loose clothing was tied up and tucked in. The lids were kept on the alcohols at all times to prevent evaporation, inhalation (which can cause dizziness) and any spillages. The Bunsen burner was kept on a yellow flame, so it was visible at all times General

  2. The Energy Content Of Different Fuels

    This means that there will be more bonds formed and so the amount of energy given out will be greater. This connects with my original prediction that this would happen but when put in to practice, my results have

  1. hydrogen peroxide experiment

    It was decided that the best way of collecting results was to measure the time it took for the oxygen to displace 30cm3 of water.

  2. GCSE Chemistry Revision Notes - everything!

    This depends on how strongly it is attracted to the nucleus in the original atom. In all of these reactions, the metal atoms are losing electrons and forming metal ions in solution. The nucleus of an atom is positive because it contains protons; therefore it attracts the negative electrons.

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