• 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

Investigating how much energy is produced when burning alcohols.

Extracts from this document...

Introduction

-1- Jack Mariner Chemistry Coursework 2 Investigating how much energy is produced when burning alcohols. In this investigation I will be burning alcohols to heat up a beaker of water. I will be burning Methanol, Ethanol, Propanol, Butanol and Pentanol. Aim 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. The energy is given out when forming the bonds between the new water and carbon dioxide molecules. The amount of energy produced by such exothermic reactions can be calculated by using the formula: Mass of the substance x rise in temp x SHC (specific heat capacity) The specific heat capacity is the number of joules required to heat one gram of water by 1�C. I chose to use water because it is safe, easily found, and has a reliable specific heat capacity of 4.2. The bonds that are formed in an exothermic reaction can be of two types. The first could be ionic, where a metal is produced. ...read more.

Middle

From these results we can work out the total energy given out per mole for each alcohol. Methanol- CH3OH Energy given out= mass of water x SHC x temperature change (Joules) (100g) (4.2) (25) = 10,500J So if 1.61g of methanol gives 10,500J Then 1g of methanol (32g) gives: 10500 1.61 X 32 =208KJ So for methanol the total amount of energy given out per mole is 208KJ. Ethanol- C2H5OH So if 1.40g of ethanol gives 10,500J Then 1g of ethanol (46g) gives: 10500 1.40 x 46 = 345KJ So for ethanol the total amount of energy given out per mole is 345KJ. Propanol- C3H7OH So if 0.75g of propanol gives 10,500J Then 1g of propanol (60g) gives: 10500 0.75 x 60 = 840KJ So for Propanol the total amount of energy given out per mole is 840KJ. -6- Jack Mariner Chemistry Coursework 2 Butanol- C4H9OH So if 0.88g of Butanol gives 10,500 J Then 1g of butanol (74g) gives: 10500 0.88 x 74 = 883KJ (to 3 s.f) So for Butanol the total amount of energy given out per mole is 883KJ. Pentanol- C5H11OH So if 2.95g of pentanol gives 10,500 J Then 1g of pentanol (88g) ...read more.

Conclusion

The plan was followed very well and the results were of good quality. The measurements were done accurately, and a fair test was achieved. The procedure used was also a very fair and efficient one. Although the experiment was a success, I am still bothered by the fact that anomalous results occured in my experiment. I think that the reasons for these results were because of time limitations and careless mistakes. We had very little time to accomplish this task successfully, so mistakes were inevitable. The improvements, which could be made in doing this experiment, are to have a longer time to do the experiment so that isn't done making careless mistake and if mistakes were made, there would be enough time to redo what was needed. Secondly more high tech equipment could be used to get more reliable and accurate results. Conclusion From 'table 2', you can see that my hypothesis is of high quality stating that 'as the amount of atoms in the alcohols increase, so will the amount of energy per mole'. This was a perfect prediction. Thus for my conclusion, I conclude that 'As the amount of atoms in the alcohol increases, so does the total amount of energy per mole.' This is the case in my results excluding any anomalous ones. Which is why this wasn't reflected as strongly as it should've been. ...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 Classifying Materials 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 Classifying Materials essays

  1. Free essay

    Periodic table

    - They generally do not conduct electricity because they are not made up of ions. - They are often insoluble in water. The formula of a compound shows the symbols of the elements that have combined to make the compound, and the ratio in which the atoms have joined together.

  2. Our experiment consisted of two samples of water containing unknown substances, and our objective ...

    Firstly, we tried to make sure we did everything according to instructions and the equipment was clean. However, in the flame test, as earlier described; we were confused over the colours of the two samples' flames since they were remarkably similar.

  1. Electrolysis COursework

    Dry them to get rid of the excess water- which is done in the same way every run. 6. Now, weigh the cathode on the top pan balance and record the mass in the table. Follow the previous steps for the remaining attempts at each voltage.

  2. Which equatoin is correct

    Bunsen burner- To provide heat for thermal decomposition. 3 Boiling tube - Boiling tubes can withstand high amounts of heat and will contain CuCO3. I will need 3 boiling tubes to conduct repeat tests so as to get the most accurate readings.

  1. The role of mass customization and postponement in global logistics

    the production line within 20 mins and rolls off in a box at the other end within the hour (www.motorola.com). * Personics Corp., a music store, allowed customers in the stores to put together their own personal compilations that were then created in 5 minutes complete with custom labels.

  2. Finding out the amount of energy given off by different types of alcohol when ...

    following are kept the same in each experiment: * Volume of water * Mass of alcohol * Starting temperature of water * Distance between flame and metal can As preliminary work earlier I investigated the amount of energy in different foods, this investigation used the same basic method as the one used in this investigation.

  1. Investigation on the combustion of Alcohols.

    I will time the experiment for 100 seconds. While I am heating the water will also be stirring the water with a thermometer so that the temperature of all of the water and not just the water at the bottom. Then when the timer has reached 100 seconds (one minute forty seconds)

  2. Combustion of Alcohol's.

    Total 2786 4706 6626 8546 10466 Right Side O=C 1610 3220 4830 6440 8050 O-H 1856 2784 3712 4640 5568 R.S. Total 3466 6004 8542 11080 13618 Overall Heat Change -680 -1298 -1916 -2534 -3152 The negative sign before each overall heat change shows that the energy was released, exothermic.

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