A-LevelChemistryChemical energeticsFeb/Mar 2021Paper 1 Q71 Mark
An experiment was performed to determine the enthalpy of combustion of ethanol. [Figure showing experimental setup for calorimetry] The data collected are shown. mass of water = Wg mass of ethanol burned = Xg temperature rise = Y°C molar mass of ethanol = Zgmol⁻¹ specific heat capacity of water = 4.2JK⁻¹g⁻¹ Which expression can be used to calculate the enthalpy of combustion of ethanol in kJ mol⁻¹?
A-4.2WYZ / 1000X
B-4.2WYX / 1000Z
C-4.2XYZ / 1000W
D-4.2X(Y+273)Z / 1000W
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