Hydrogen sulfide gas is a poisonous gas with the odor of rotten eggs. It occurs in natural gas and is produced during the decay of organic matter, which contains sulfur. The gas burns in oxygen as follow:
2H2S(g)+3O2(g)->2H2O(l)+2SO2(g)
Calculate the standard enthalpy change for this reaction using standard enthalpies of formation.
Okay so here is my work after using the standard enthalpy chart to determine the ∆Hf˚
2H2S(g)=-20.5 kJ/mol
3O2(g)=0 kJ/mol
2H2O(l)=285.8 kJ/mol
2SO2(g)-296.8 kJ/mol
I put them into the reaction ΔH° = Σ(ΔHf°products) - Σ(ΔHf°reactants) which looked like this
ΔH° =(2molH2O×285.8/1)+(2molSO2×(-296.
/1)- (2molH2S×-20.5/1)+(3molO2×0/1) =19kJ/mol
But the answer is supposed to be -1124.2kJ, can anyone tell me what I did wrong here?