Question

When sucrose (C12H22011) reacts with molecular oxygen, the products are carbon dioxide gas and liquid water. The reaction releases 5639.7 kJ of heat. Calculate the enthalpy of formation for sucrose.

Answer 1

C12H2201, (g)12 02(g)-12 CO2(g)+11H20 (I) Products Reactants Given that the standard enthalpies of formation for co, is -393.51 kJ/mol, enthalpies of formation for H,0 is -285.83 kJ/mol, and enthalpies of formation for O, is 0.0 kJ/mol And the standard enthalpies of combustion of sucrose is -5639.7 kJ/mol The enthalpies of formation of pure element like oxygen gas, hydrogen gas is always zero. The general equation for standard enthalpy of combustion is as follows: [Σ -AHGH20 120;) ΔΗ AH120+11H0) AH 120) -ΣΔΗ -ΔΗ AH CaH220+120) (12CO2+11H2O) -ΣΔΗ0-11Η,0 ΣΔΗ0 -ΔΗ -4722.12kJ -3144.13 kJ-(-5639.7 kJ) =-2226.55 kJ