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The Combustion rate of Alcohols and how much energy is required to break their bonds

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Introduction

Lordswood Boys School My Investigation H Name : Alex Byrd Set: 11Z The Combustion rate of Alcohols and how much energy is required to break their bonds Planning I am going to investigate what happens when I heat some water using sprit burners containing different alcohols and then find how much mass was lost. As I am going to be heating water up then some way or another I will be losing heat, plus if I'm in a room with a window open then the flame will be disturbed and the beaker will cool down from the cool air coming through. To help prevent this I shall put cardboard pieces around the flame to protect the flame and the beaker. I am going to use a copper container because it conducts heat better and so there will be better results. Diagram Sprit burners: Propanol Methanol Hexanol Ethanol Pentanol Copper beaker 50 ml water Clamp stand Clamp claw 4 cardboard tiles Heat proof mat Splint Lighter Measuring cylinder 1) Firstly set up the clamp stand and attach the clamp claw to it. ...read more.

Middle

I am going to use 5 different alcohols and repeat the experiment 3 times then I am going to take an average result. I predict that the alcohols with the bigger Carbon chain will need more energy to burn, because there are more bonds and so it is harder to break them all up. Science Theory I predict this because I have calculated the energy required to break the hydrocarbon bonds. I did this by working out the mass of the reactants and taking this away from the products. The results show that to break the methanol hydrocarbons would require less energy than to break the pentanol hydrocarbon and even more energy is required to break octanol hydrocarbons. This is because the structure of the carbon atom, each carbon atom is covalently linked to four hydrogen atoms this causes a structure of great hardness. This means that methanol will lose the most mass because less energy is needed to break the bonds. ...read more.

Conclusion

My prediction was correct because what I predicted in theory is true. Evaluating Problems There weren't many problems that faced me with the experiment. Accuracy. My results are as accurate as I could possibly get them, I tried to do an accurate fair test but without the exact equipment heat would always be lost and cause inaccuracies in my results. If I were to re-do my experiment I would investigate ways in which I could retain the heat maybe by surrounding the spirt burner in tin foil and around the metal container. If I were able to do this safely then I would be able to get more accurate results, which then may prove my theory correct. Odd Results. There weren't any odd results. Firm Conclusion Looking at my results and the results I was able to obtain I conclude that the smaller the hydrocarbon chain the less energy is needed to break the covalent bonds so more mass will be lost. The longer the hydrocarbons the more energy is required so less mass will be lost. ...read more.

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