Question

ormation Reactions Review Constants Part B The standard heat of formation, AH is defined as the enthalpy change for the formation of one mole of substance from its constituent elements in their standard states. Thus, elements in their standard states have AH O . Heat of formation values can be used to calculate the enthalpy change of any reaction. The combustion of propano, C, Hs. cocurs via the reaction CH, (B) +502 (6)+3CO2 (s) + 4H2O(g) with heat of formation values given by the following table: Substance (kJ/mol Consider, for example, the reaction 2NO(g) + O2(e) = 2NO, (8) with heat of formation values given by the following table: Γ ΔΗΣ Γ ΔΗ 047 Substance (kJ/mol) CH CO, (8) H,OR) - 241.8 NO() 0.(g) NO,(g) 90.2 0 332 Calculate the enthalpy for the combustion of 1 mole of propane. Express your answer to four significant figures and include the appropriate units. View Available Hints) Then the standard heat of reaction for the overall reaction is AH - AH (products) - AH (reactants) = 2(33.2) - 2(90.2) +01 114 kJ at - O! Value RO? Units Submit

Answer 1

4nswer peleaseoe Enthalpy of Combustion the amount enerrgy When Imole of a eempocnd is bvened in ercess Oxgen to prolee prestuets presswre Machernaticaly AHAaM-ZAH Cpnsuet)-AH eacea ne at 298 and latm eis expicesseol ais Now cansideing the dsmbusei'on preapane Geven, 4Hf He )104.-4 K/m 4H 02= -393.5 KT/moc AH O70cg) = 241.8 KT/mst It is important to note that AH 0,9)=O KJ/mr 14 as re coming directty feom aemerphere ZAHpratuc 3xAfH(co,) +4x AHC) xC-393.5+14x -24 1.2 = 1180.5-96 7.2) KJ/mo = -214 7.7KJ/moe KT/mst Ces tte) SxAHfCo xC-I04- x KT/me +5x ZAHRCHeactant) 11 = -104-子KImoc

2 AH goececluct -2AH Ceractane 2147.7t 104.7) KJ1mol 22524 K1T/n 2252*+0Ttmat -2043 KTms = - 2.043x (06mote Thees the enthalpy csmbustion f pecspane Cmo - 2.043 X ID T/mot will be