Chemistry - Thermochemistry Question with Solution | TestHub
ChemistryThermochemistryEnthalpy of CombustionHard2 minQB
ChemistryHardsingle choice
From the following data, calculate the enthalpy change for the combustion of cyclobutane(g) at 298 K. The enthalpies of formation of CO2(g), H2O(l) and 1-butene(g) are -394, -286 and +1 kJ/mol, respectively. The enthalpy of isomerization of cyclobutane(g) to 1-butene(g) is -27 kJ/mol.
Options:
Answer:
A
Solution:
1-Butene: C4H8 + 6O2 → 4CO2 + 4H2O. ΔHc(1-butene) = 4(-394) + 4(-286) - (+1) = -1576 - 1144 - 1 = -2721 kJ. Cyclobutane first isomerises to 1-butene, releasing 27 kJ, so ΔHc(cyclobutane) = -27 + (-2721) = -2748 kJ/mol. This is option (a).
Stream:JEESubject:ChemistryTopic:ThermochemistrySubtopic:Enthalpy of Combustion
⏱ 2mℹ️ Source: QB
Doubts & Discussion
Loading discussions...
