CHEMISTRY, M4 EQ-Bank 38v4

Methanol () is a hydrocarbon fuel which combusts completely according to the following equation:

A chemist burns 0.40 g of methanol in excess oxygen during a calorimetry study, and the heat energy is used to heat 80.0 g of water. The initial temperature of the water in the calorimeter is 24.0 °C, which rises to a maximum of 52.0 °C after absorbing the energy from the combustion reaction. Based on these results, calculate the experimental molar heat of combustion () for methanol. (4 marks)

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The experimental molar heat of combustion () for methanol is . (2 sig.fig.)

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Calculate the energy absorbed by the water:

Calculate the number of moles of methanol burned:

Calculate the molar heat of combustion:

→ The experimental molar heat of combustion () for methanol is . (2 sig.fig.)