The enthalpy of combustion of table sugar (sucrose, C₁₂H₂₂O₁₁, 342.3 g/mol) is -5,643 kJ/mol. What is the food value (Cal/g) of sucrose? (1 Cal = 4.184 kJ)

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To find the food value in Cal/g of sucrose, first convert the enthalpy of combustion from kJ/mol to Cal/mol by dividing by 4.184 kJ/Cal: 105,643 kJ/mol ÷ 4.184 kJ/Cal = 25,260 Cal/mol. Then, divide by the molar mass of sucrose (342.3 g/mol) to find the value in Cal/g: 25,260 Cal/mol ÷ 342.3 g/mol = 73.8 Cal/g. The provided options seem to be incorrect based on the calculation, but if we were to follow the same method with correct values or options, we would divide the given enthalpy by 4.184 to convert kJ to Cal and then divide by the molar mass to get Cal/g. None of the options match the calculated value, suggesting a possible mistake in the calculation or in the interpretation of the options. Given the options and the typical energy content of sucrose, option A seems to be the closest to a reasonable value, but it does not match the calculated result based on the provided data and conversion factors.

The Enthalpy of Combustion of Table Sugar (Sucrose, C12H22O11, 342

The Enthalpy of Combustion of Table Sugar (Sucrose, C₁₂H₂₂O₁₁, 342