Organic chemistry

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Question 12
Medium

In an investigation into the enthalpy of combustion of different alcohols, a student used a copper calorimeter to measure the energy released per gram of fuel burned. Due to heat losses to the laboratory surroundings, the experimental energy values obtained were lower than standard values. The student's recorded data is shown in the table below.

AlcoholFormula of one molecule of the alcoholExperimental energy released in kJ/g\text{kJ/g}kJ/g
MethanolCH3OH\text{CH}_3\text{OH}CH3​OH19.819.819.8
EthanolC2H5OH\text{C}_2\text{H}_5\text{OH}C2​H5​OH26.426.426.4
PropanolC3H7OH\text{C}_3\text{H}_7\text{OH}C3​H7​OH29.129.129.1
ButanolC4H9OH\text{C}_4\text{H}_9\text{OH}C4​H9​OH31.831.831.8
PentanolC5H11OH\text{C}_5\text{H}_{11}\text{OH}C5​H11​OH33.533.533.5
OctanolC8H17OH\text{C}_8\text{H}_{17}\text{OH}C8​H17​OH36.236.236.2

Calculate the mass of methanol that must be burned to release the same quantity of heat energy as is released by burning 1.85 g1.85\text{ g}1.85 g of butanol under these experimental conditions.

Give your answer to 3 significant figures.

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Organic chemistry Questions

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  3. /Organic chemistry