• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Find out the amount of energy released when burning different alcohols.

Extracts from this document...


Chemistry Coursework - Combustion of Alcohols Aim: To find out the amount of energy released when burning different alcohols. Hypothesis: I predict that octan-1-ol will release the most heat energy. This is because there is more bond energy in that molecule than the other alcohols. Within a molecule there are bond energies that are holding the atoms together. When the fuel combusts a chemical reaction takes place, this breaks the bonds, this requires energy, and makes new bonds this gives out energy. The energy differences between the two tell us how much energy was given out or taken in. We can show this on a graph. Planning: In this investigation I will be burning alcohols to heat up a can of water. I will be burning seven alcohols, Ethanol, Propan-1-ol, Butan-1-ol, Pentan-1-ol, Hexan-1-ol, Heptan-1-ol, Octan-1-ol. The aim is to find out how much energy is produced when burning these alcohols. 'An alcohol is a series of organic homologous compounds, with the general formula Cn H n + 1OH�. Alcohols react with oxygen in the air to form water and carbon dioxide. The reaction that is involved in burning alcohols is exothermic because heat is given out. ...read more.


The alcohol has to be blown out immediately when the water temperature has been raised 30 degrees; it must be covered after the experiment to avoid evaporation. The thermometer must be swirled around the water before a reading can be taken, this insures that you are measuring the temperature of the whole water not just the bottom of the can. The shape of the spirit lamp must stay the same and so must the wick length. If all this is done we can ensure that we will get an accurate reading. Method: * Record initial mass of alcohol plus burner, this is so that at the end of the experiment the alcohol and burner can be measured to get the results. * Measure out 100cm3 of water in to the copper can using measuring cylinder. * Stir and record initial temperature of water, so you can calculate the amount of temperature rise later. * Start clock and light burner at the same time, so the timing of the experiment is exactly right. * Place can so flame is 3 cm from the bottom of the it, * Stir water, so the temperature is spread among all of the water in the can. ...read more.


Since heat is given out when bonds form, less energy is given out by incomplete combustion. So this is why it affects the outcome of the experiment. To make this problem irrelevant I could have made sure a constant supply of oxygen was present in the experiment. Fuel Initial mass of alcohol Final mass of alcohol Mass burnt Temperature of water before Temperature of water after Temperature rise Ethanol 221.59g 220.24g 1.35g 23�C 37�C 14�C 219.49g 218.36g 1.13g 23�C 36�C 13�C 218.03g 216.71g 1.32g 23�C 35�C 12�C Propan-1-ol 182.82g 182.57g 0.3g 20�C 40�C 20�C 182.22g 181.61g 0.61g 21�C 34�C 13�C 181.57g 180.57g 1g 21�C 55�C 14�C Butan-1-ol 208.35g 205.20g 3.15g 25�C 37�C 12�C 205.20g 202.86g 2.34g 23�C 32�C 9�C 202.86g 200.59g 2.27g 21�C 30�C 9�C Pentan-1-ol 211.89g 210.20g 1.69g 20�C 30�C 10�C 210.30g 208.29g 2.01g 20�C 28�C 8�C 208.29g 206.81g 1.48g 21�C 27�C 6�C Hexan-1-ol 216.84g 214.61g 2.23g 20�C 30�C 10�C 214.61g 212.81g 1.8g 30�C 43�C 13�C 212.81g 210.81g 2g 21�C 34�C 13�C Heptan-1-ol 207.8g 206.95g 0.85g 22�C 40�C 18�C 206.95g 206.36g 0.59g 19�C 36�C 17�C 206.36g 205.87g 0.49g 20�C 36�C 16�C Octan-1-ol 222.09g 220.50g 1.59g 20�C 30�C 10�C 220.50g 218.74g 1.76g 28�C 30�C 2�C 218.74g 217.20 1.54 37�C 40�C 3�C Graph of averages: Averages: 1. 13 2. 15.6 3. 10 4. 8 5. 18.6 6. 17 7. 5 ...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. The energy produced of different alcohols.

    touch the bottom of the calumeter for each experiment knowing it will be a fair test. I will also have the same thermometer and the same amount of water in the calumeter. The thermometer would be fixed in the middle of the calumeter to give the reading of just the

  2. How Does The Increase In The Length Of The Carbon Chain Affect The Energy ...

    The energy loss is due to bad insulation or by excess energy escaping through the top of the calorimeter as a lid was not used. Additionally there is the possibly of anomalous results from either the balance or the thermometer readings.

  1. The Energy Content Of Different Fuels

    Temperature rise= (89-22)= 67?C 2. Mass of fuel used = (235.3-234) = 1.3g 3. Molar mass of C5H11OH = 88 No. of moles = mass Molar mass No. of moles = 1.3/ 88 = 0.014772727 moles of fuel used 4. Energy used & produced to = mass of water X S.H.C X Temp rise heat

  2. Molar Heat of Combustion of Alcohols

    One of the mistake we made whilst performing the experiment was not to label the calorimeter we used as to make sure we used the same one again, this may have cause large inaccuracies because there is the possibility the copper may be thicker on one than the other.

  1. To find out how much energy is produced when burning two hydrocarbons, Ethanol and ...

    2nd test J/g 7980�1.2=6650 It appears that the paraffin caused the greatest rise in temperature and therefore must have released the bigger amount of energy when burned. Evaluation I believe my results were very inaccurate. Below is a list of reasons why it was an inaccurate experiment.

  2. The energy released by an Homologous series of alcohols

    The table below show the results of this experiment. Fuel Mass before (grams) Mass After (grams) Mass change (grams) Temperature at 30 secs Temperature at 60 secs Temperature at 90 secs Temperature at 120 secs Ethanol 254.8 252 2.8 28 42 55 69 The chemical equation for this exothermic reaction

  1. An investigation into the heat energy released upon burning different fuels

    Here is ethanol's energy level diagram to show how bonds are broken and made to finally produce the net energy out. This tells us that there is more energy given out when bonds are made than taken in when bonds are broken.

  2. GCSE Chemistry Revision Notes - everything!

    There are many ways of achieving this. They include: 1. Painting. A coat of paint prevents oxygen and water coming into contact with the iron. But this only works while the coating of paint is unbroken. This type of rust prevention is used to prevent car bodies or iron railings rusting.

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