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

Combustion of alcohols

Extracts from this document...


David Downs Combustion of alcohols I aim to investigate the heats of combustion in comparison to the number of atoms in the molecule between different alcohols. To do this I will heat some water in a beaker until it has risen in temperature significantly and then will weigh it in order to establish the change in mass thus to work out the heats of combustion. I will use the equation E=MC T and the specific heat of water (4200j) to calculate the heats. In this equation E is the energy required to raise the waters temperature to the specified heat (j), M is the mass of water in the beaker (kg) and C is the specific heat. is a Greek letter used in Chemistry to symbolise 'change in'. Therefore T is the change in temperature (?c). An alcohol is a water molecule with an alkyl group in place of one of the Hydrogen atoms. ...read more.


4. Note the starting temperature of the water. 5. Place the burner under the can and ignite it. 6. Monitor the temperature until it reaches the desired change and then extinguish the flame. 7. Re-weigh the burner once it has cooled (handling it only with the clasps at first) and then deduce the change in weight. 8. Repeat this for all 4 alcohol samples. (To improve the efficiency of the experiment changes could be made such as using a heat shield or coating the inside of the tin with heat resistant paint. However I have chosen not to employ these methods because of practicality and lack of materials even though they would undoubtedly improve the accuracy of the experiment.) Safety * Basic lab safety precautions should be observed while conducting any experiment. * When fire is involved special care is needed and all apparatus must be handled with caution and the correct equipment. * As most of the equipment is metal then the heat will conduct throughout the apparatus and so all parts must be handled with caution. ...read more.


The gradient of the graph re-enforces this, as it increases in gradient. The overall conclusions of this experiment agree with the facts laid down by the textbook Cambridge advanced sciences, Chemistry 1 and so can be assumed to be reasonably accurate. However the small errors that were made could be eliminated should the experiment be repeated. Errors such as the heat loss through the can. Introducing a heat shield or using a can made of a material with less heat conductivity could reduce this. If I were to require more accurate results I would conduct the experiment under such circumstances to give better results. However I think that the results I have obtained are sufficient to draw limited conclusions from and therefore are deemed adequate. However if I were to require more accurate conclusions more accurate results would need to be obtained form another experiment. Further experiments were not conducted due to lack of time. ...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. Marked by a teacher

    Experiment to investigate the heat of combustion of alcohols.

    4 star(s)

    With increasing molecule length, there is an increase in I had also plotted a further graph to compare with my results that I had obtained from a data sheet, informing me of the energy values needed to break certain bonds.

  2. Investigating the Combustion of Alcohols

    = 75 � -4.2 � 25 = -7875 J The number of moles of propan-1-ol burned is calculated by the following steps: Mass of 1 mol of propan-1-ol, C3H7OH = (12�3) + (8�1) + 16 = 60 g Number of moles of propan-1-ol burned = mass burned mass of 1

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

    The way to explain this is because the existing bonds between the alcohol and the oxygen are broken. To do this we must provide the activation energy to start off the reaction. This requires a spark or a burning splint to light the flame to supply this activation energy.

  2. Molar Heat of Combustion of Alcohols

    Trial Experiment Results First Experiment Butanol Boiling Tube Beaker Copper Calorimeter Initial temperature of water (OC) 20 22 18 Final temperature of water (OC) 33 68 47.5 Temperature difference (OC) 13 46 49 Initial mass of Ethanol (g) 92.44 94.41 66.23 Final mass of Ethanol (g)

  1. To investigate the relationship between the structure and heat produced by combustion for a ...

    as it is high quality in that it burns with a large clean flame, two signs of complete combustion. The combustion reaction of ethanol is as follows: Ethanol + Oxygen ? Carbon Dioxide + Water C2H5OH (l) + 3O2 (g)

  2. Chemistry Course Work: Combustion of Alcohols

    should produce the greatest heat loss, as more energy is required to brake the bonds. The Chemical Formulas for the five alcohols that we will use in this experiment are listed bellow. Hexan-1-ol = C6H13OH Pentan-1-ol = C5H11OH Butan-1-ol = C4H9OH Propan-1-ol = C3H7OH Ethanol = C2H5OH From the above

  1. To investigate the combustion of alcohols.

    These reactions must be heated. E.g. with a Bunsen burner. I will need to find out the energy values for the alcohol and oxygen reactants, then compare these with the energy values for the carbon dioxide and water products. Bond Average bond energy in Kj/mol H-O 463 O=O 498 C-C

  2. GCSE Chemistry Revision Notes - everything!

    Most sulphates are soluble (except lead, barium and calcium). Salts have different methods of production depending on whether the reagents needed are soluble or not. In the first method a metal or an insoluble base or insoluble carbonate with an appropriate dilute acid. This method cannot be used with unreactive metals such as copper or with very reactive metals such as sodium.

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