• 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

# To Investigate the Combustion of Fuels

Extracts from this document...

Introduction

To Investigate the Combustion of Fuels Plan A fuel is a substance from which energy can be obtained, usually by combustion. I have chosen to use four different alcohols as fuel - methanol, ethanol, propanol and butanol. We can measure how much energy is released by putting the burning fuel under a beaker of water, and recording how much the temperature goes up by. Then the equation E = MC?T is used, where: E = Energy Released M = Mass of material heated C = Specific heat capacity of the material. For water this is 4.2 ?T = Temperature change Method For this investigation I will need: Clamp Stand Metal dish Conical flask Bunsen burner Thermometer Measuring cylinder Wooden splints Scales Water Four spirit burners containing ethanol, methanol, propanol and butanol I will set up this equipment as shown below. First I will light the Bunsen burner, and make sure it is at least a metre away from the rest of my apparatus. Then I will measure out 100ml of water (which equals 100g) using the measuring cylinder, and pour it into the conical flask. Next I will record the temperature of the water using the thermometer, and record the total mass of the spirit burner with its lid on using the scales. I will take the lid off the spirit burner, and set the distance between the top of the wick and the bottom of the beaker to 10cm. ...read more.

Middle

Although I would expect my actual results to follow the same pattern as my predicted results, I would only expect my actual results to be a small fraction of them. This is because not all of the energy will get to the water for reasons such as: - Some energy is used to heat the container. - Energy heats up the surroundings due to radiation and convection currents. - Draughts disperse energy. Preliminary Experiment I carried out a preliminary experiment to help me decide how to conduct my actual experiment. In it I used the same basic method found in my actual experiment. Fuel Height of flask above wick (cm) Mass of Water (g) Mass of spirit Burner(g) Temperature (oC) Time (s) Before After Before After Methanol 5 50 248.42 247.76 22 32 44.93 Methanol 5 100 247.76 246.81 19 29 67.22 Butanol 5 100 271.94 271.54 22 32 31.27 Butanol 10 100 271.54 270.84 22 32 62.49 Things I found out: -50g of water is not enough to cover the whole thermometer bulb. 100g are sufficient. -The height should be measured from the top of the wick to the bottom of the flask. 10cm should be used here, as if the distance is less, when using butanol a black layer of carbon is left on the bottom of the flask. -The temperature will be allowed to rise by 10oC before the flame is put out, as this takes an appropriate amount of time to do. ...read more.

Conclusion

Although my results agreed partly with my predictions, by the alcohols that had more carbon and hydrogen molecules releasing more energy than the alcohols with less, it disagreed in that in my prediction, as the number of carbon atoms increased, I predicted the amount by which the energy released goes up would decrease, but my results showed that as the number of carbon atoms increased, the amount by which the energy released goes up also increased. This, combined with the large amount of anomalies and the amount that my results were spread out, gives an unreliable conclusion. In the experiment with methanol, where I only had one anomaly, the highest amount of energy that I recorded to be released was 3111.11 J g-1, which was roughly 30% bigger than the smallest. I had to include both results, though, as the third result was right in the middle of the two, so I could not say which one was anomalous and which was correct. If I had taken another reading, I might have been enough to decide, and it would make my evidence more reliable. If I had more time to study the combustion of fuels, I would look at alcohols further along in the chain, such as pentanol. I would also look at how quickly energy is released by different fuels. For this I would set up the experiment in virtually the same way, but I would put out the flame after a minute and measure how much 100g of water rises in temperature in that 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

# Related GCSE Organic Chemistry essays

1. ## Experiment to investigate the heat of combustion of alcohols.

4 star(s)

I believe that I had conducted the experiment accurately, and recording enough results to provide a sound conclusion. There weren't many flaws to my technique as each experiment proved successful. However there are some areas of inaccuracy during the experiment that would have altered the readings: 1.

2. ## THE LINK BETWEEN CARBON ATOMS IN A FUEL AND THE ENERGY IT RELEASES.

mass of calorimeter ? specific heat of calorimeter) The specific heat of copper calorimeter is = 0.385 * Heat evolved in methanol 1st attempt = (4.2?75.22?4.2) + (4.2?77.21?0.385) 1326.8808+124.84857 1451.72937joules. 2nd attempt = (5.0?75.30?4.2) + (5.0?77.21?0.385) 1581.3+148.62925 1729.92925joules. 3rd attempt = (5.6?74.93?4.2) + (5.6?77.21?0.385) 1762.3536+166.46476 1928.81836joules. Heat evolved in ethanol 1st attempt = (4.8?76.33?4.2)

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

Doing experiment and investigations are the best ways of obtaining the enthalpy of alcohols, but in this particular experiment it was too inefficient to gain any reliable results. During the experiment I noticed a lot of heat loss. Although the draft excluder did limit the amount of heat lost to

2. ## Energy Released From the Complete Combustion of Different Alcohols

X ?H = M x 4.18 x (t2-t1) ?H Propanol = = - 717.654 kJ/mol c) With Butanol: 1- The mass of spirit burner before heating = 259.91 g 2- The mass of empty can = 29.91g 3- The mass of can with water = 226.45 g 4- The mass of water = 196.54 g 5- The initial

1. ## Comparing fuels

If there is a limited supply of oxygen then you get carbon monoxide (each carbon atom can only bond with one oxygen atom). This is when incomplete combustion has occurred. This is so because the carbon monoxide could react some more to make carbon dioxide.

2. ## Energy Transfer in Fuels

However, the fuel, Butanol produced quite an anomalous result as this had more carbon atoms than Ethanol, which produced a larger energy transfer than Butanol. This is quite an unexpected result as we were extremely careful on making the experiment a fair test and careful on how we specified certain

1. ## Find out the heat of combustion in the five fuels; Methanol, Ethanol, Propanol, Butanol, ...

Temp difference Water Cubic cm Mass of fuel .end. Water temp end. Methanol 12.545 24 C 8 C 30cc 11.98 31 C Ethanol 12.685 23 C 8 1/2 C 30cc 12.175 31 1/2 C Propanol 12.6 26 C 15 1/2 C 30cc 12.08 41 1/2 C Butanol 12.415 25 1/4

2. ## 'Enthalpy of Combustion'.

The very accurate figures in the data book increase at a higher rate of 652 kJ (average) per carbon atom. The middle line on the graph is the line plotted for the theoretical heat of combustion that was calculated in the planning.

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