Organic chemistry

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Question 36
Medium

A research chemist is investigating the thermal efficiency of various liquid biofuels. The chemist combusts samples of different straight-chain alcohols under standard laboratory conditions to determine the energy released per gram.

Table 1: Energy released by the combustion of alcohols

AlcoholChemical formula of alcohol moleculeEnergy released in kJ/g\text{kJ/g}kJ/g
EthanolC2H5OH\text{C}_2\text{H}_5\text{OH}C2​H5​OH29.8
PropanolC3H7OH\text{C}_3\text{H}_7\text{OH}C3​H7​OH33.5
ButanolC4H9OH\text{C}_4\text{H}_9\text{OH}C4​H9​OH36.0
PentanolC5H11OH\text{C}_5\text{H}_{11}\text{OH}C5​H11​OH37.8
HexanolC6H13OH\text{C}_6\text{H}_{13}\text{OH}C6​H13​OH39.0
HeptanolC7H15OH\text{C}_7\text{H}_{15}\text{OH}C7​H15​OH40.2

Calculate the mass of ethanol that must be completely burned to release the same amount of thermal energy as burning 4.80 g4.80\text{ g}4.80 g of hexanol. Give your answer to 3 significant figures.

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Organic chemistry Questions

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