Report the calculated and experimental combustion enthalpies of H2, CH4 , C2H4.
ID: 768474 • Letter: R
Question
Report the calculated and experimental combustion enthalpies of H2, CH4 , C2H4. Report the equilibrium constants for each reaction. Are all of these spontaneous? Rank the fuels in terms of energy released per gram combusted. Rank the fuels in terms of energy released per L combusted.Explanation / Answer
1.Del.H=92.4J energy released 2.CH4 (g) + 2 O2 (g) ? CO2 (g) + 2 H2O (l) ?Hocomb = 2 ?Hof,water + ?Hof,carbon dioxide - ?Hof,methane - 2 ?Hof,oxygen ?Hocomb is measured experimentally. ?Hof,oxygen = 0, because oxygen is a pure element. The other molar enthalpies of formation are known from independent measurements. For example, one could determine the heat of combustion of hydrogen to obtain the molar enthalpy of formation for water. For liquid water, ?Hof = -285.8 kJ mole-1 3.For gaseous carbon dioxide, ?Hof = -393.5 kJ mole-1 C2H4(g) + 3O2(g) --> 2CO2(g) + 2H2O(g) ?H rxn = ?H prd - ?H react = -1411.1 kJ/mole ?H prod = 2 * (-393.5kJ) + 2 (-285.9kJ) = -1358.8. Homework & Coursework Questions > Other Sciences. 1. The problem statement, all variables and given/known data In a calorimeter, a 1.0g. If 1g of magnesium. The heat ( enthalpy) of combustion of glucose, C6H12O6, is -2800 kJ/mol. a) What is ?E for the combustion of glucose at 25 oC