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

Enthalpy of Combustion Lab Report

Extracts from this document...

Introduction

22/9/2008 Dhruva Mahimtura Enthalpy of Combustion of Ethanol Aim: The aim of the following experiment is to determine the enthalpy change of combustion of ethanol when one mole of ethanol is burned completely with the help of a spirit lamp for a time period of one and a half minutes. Background: Specific Heat Capacity is the amount of heat required to raise the temperature of 1g of a substance by 1K. ? � Differs from substance to substance. ? � Water = 4.18 J g-1 K-1? � Ethanol = 2.4 J g-1 K-1 The data booklet value for the standard enthalpy of combustion of ethanol is -1371 KJ/mol. Apparatus: Instrument / Chemical: 1. Spirit lamp containing ethanol 2. Copper Calorimeter 3. Distilled Water 4. Stop Watch (?0.01s) 5. 1?50cm3 beakers 6. Retort Stand 7. Digital Thermometer (?0.1) 8. Digital Electronic Balance (?0.01g) 9. Stirring rod Method: 1. The mass of the spirit lamp containing ethanol is first determined accurately with the help of the digital electronic balance and is recorded as M1 (?0.01g). 2. Then a copper calorimeter is taken and the mass of the empty calorimeter is first determined. Then the calorimeter is filled with distilled water and the mass of the calorimeter along with water is then recorded. The two readings are then subtracted to determine the mass of the distilled water used in the experimental procedure with the help of the digital electronic balance and is recorded as M3 (?0.02g). 3. Then the calorimeter containing the water is placed on top of the retort stand and the digital thermometer is used to ...read more.

Middle

Raw Data: Initial mass of spirit lamp = M1, Final mass of spirit lamp = M2, Mass of distilled water used in the experimental procedure = M3, Initial temperature of water = T1, Final temperature of water = T2, The following table N1 shows the raw data that has been recorded in order to determine the enthalpy change of combustion of ethanol while conducting the following experimental procedure: Sr. No. M1 (?0.01g) M2 (?0.01g) M3 (?0.02g) T1 (?0.1) T2 (?0.1) 1. 168.50 166.85 121.16 - 42.94 = 78.22 27.2 38.2 2. 166.85 165.61 121.02 - 42.94 = 78.08 37.4 45.4 3. 159.00 157.50 126.26 - 43.53 = 82.73 26.5 36.2 4. 157.50 155.75 126.08 - 43.53 = 82.55 35.8 45.8 5. 155.75 154.44 125.83 - 43.53 = 82.30 44.3 51.1 Processed Data: Mass of ethanol that has been used and burnt completely = M1 - M2 = MF, Rise in Temperature of the distilled water when the spirit lamp is placed directly below the calorimeter = T2 - T1 = TF, The following Table N2 gives the values of the mass of ethanol that has been used and the change in temperature of the distilled water solution. Sr. No. MF (?0.02g) TF (?0.2) 1. 168.50 - 166.85 = 1.65 38.2 - 27.2 = 11.0 2. 166.85 - 165.61 = 1.24 45.4 - 37.4 = 8.0 3. 159.00 - 157.50 = 1.50 36.2 - 26.5 = 9.7 4. 157.50 - 155.75 = 1.75 45.8 - 35.8 = 10 5. ...read more.

Conclusion

3. It is assumed that the glass stirrer, the digital thermometer and the calorimeter were not absorbing any heat but in reality these instruments are also being heated. 4. It is assumed that none of the ethanol escaped through evaporation during the time the flame was extinguished and the spirit lamp and its contents were reweighed. However, ethanol is a volatile liquid and the fact that the spirit lamp was hot indicates that some of it would have evaporated. Conclusion: In the carried experimental procedure one has determined the enthalpy change of combustion of ethanol when one mole of ethanol is burned completely with the help of a spirit lamp for a time period of one and a half minutes. One has successfully proven the hypothesis that has been made earlier. I had predicted beforehand that the reaction-taking place in the experimental procedure is an exothermic one. The fact that heat is given out when ethanol is burnt has been depicted by the temperature rise of the distilled water present in the calorimeter. Hence it is clearly evident that the combustion reaction of ethanol is an exothermic reaction. Suggestions for Improvement / Evaluation: 1. There should not be any disturbance in the room where the experiment is being conducted as one is trying to prevent any interference to the internal system. 2. While conducting the experiment, one should use a shield like device in order to cover the entire apparatus and prevent any heat transfer between the surrounding and the internal system. 3. More efficient equipment should be used in the conducted experimental procedure. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate 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 International Baccalaureate Chemistry essays

  1. Lab Report - Flame Test

    Observations:- Metal Salt Colour of the Flame Sodium Chloride Golden yellow Sodium Carbonate Golden yellow Sodium Sulphate Golden yellow Lithium Chloride Red Potassium Chloride Lilac

  2. Enthalpy of Combustion of Alcohols Lab

    Finally, we will divide the heat energy by the number of moles to calculate the enthalpy of combustion of the alcohol. ?H = mC?T n QUANTITATIVE DATA: COMBUSTION OF ALCOHOLS Alcohol Type Mass of Methanol before burning (g) ?0.01g Mass of Methanol after burning (g)

  1. Enthalpy Change Design Lab (6/6)How does changing the initial temperature (19C, 25C, 35C, and ...

    as to ensure the level of agitation of the solution is consistent. Materials and Equipment: - 2 x Clean, dry, polystyrene cups - 2 x Temperature probe (+/- 0.3�C) - 2 x Vernier LabQuest interface wih Logger Pro data collection software - 1 x Electrically powered magnetic stirrer - 1

  2. Rates of Reaction Lab

    Though two trials for all three concentrations is good enough to prove the point, using higher and lower concentrations of acid and repeating trials for each would provide better experimental data to prove the hypothesis correct. Improvements One of the very first actions that I would take in order to improve the experiment is modify the design of the experiment.

  1. The aim of this experiment is to examine the enthalpy of combustion of the ...

    180 52.5 50.0 50.0 51.0 210 52.0 49.5 49.5 50.0 Qualitative data Soot was not formed on the boiling tube.The flame was in dark orange,slightly waving because of the movements. It is assumed that the heat could not have been transferred completely in the boiling tube because of that.

  2. Determination of Heat of Combustion of Ethanol

    This is probably what led the result to be so much smaller. The experiment was not conducted under STP which is another cause for the large uncertainty. Evaluation 1. The major cause for the systematic error was the fact that the can absorbed heat.

  1. To determine the standard enthalpy of formation of Magnesium Oxide using Hess Law.

    Qualitative Observations At the reaction site (calorimeter), the solution was bubbling. This indicated the production of Hydrogen gas. The origin of the bubbles was the surface of the Magnesium strip.

  2. Chemistry Lab Report- Determining the Enthalpy of Enthalpy Change, H, for a Redox Reaction ...

    Number of Moles (Cu + Zn2+) = Mass/Mr Mass=Mass of CuSO4 Solution (g) (±0.05g) + Mass of Zinc Powder (g) (±0.05g) Mass= 25.0g (±0.05g) +4.0g (±0.05g) Mass= 29.0g (±0.05g) Convert to Kg: 29.0g/1000= 0.0290Kg Mr= Cu-1; 63.55 x 1=63.55 S-1; 32.06 x 1=32.06 O-4 16.00 x 4=64.00 Total relative mass

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