... a substance burns completely in oxygen (always -ve). To work out the enthalpy change of combustion of the alcohols the energy output must be measured. The easiest way to do this accurately is to use the thermal energy of combustion to raise the temperature of a substance with a known specific heat capacity, (the amount of energy required to increase the temperature of 1g of a liquid by 1°C).We will be using water. Prediction I predict that the longer the hydrocarbon chain the more energy will be transferred to the water, therefore fewer moles of fuel will be used to achieve the same temperature rise. So as the number of carbon atoms increases the enthalpy of combustion will become more negative. Alcohols to be used to compare * Methanol = CH3OH * Pentan-1-ol = C5H11OH * Propan-1-ol = C3H7OH * Propan-2-ol = C3H7OH * Butan-1-ol = C4H9OH * Butan-2-ol = C4H9OH I have chosen these alcohols because I will have a chain containing 1 carbon atom, 3 carbon atoms, 4 carbon atoms and ...

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