The reaction of cyanamide, NH2CN(s) with oxygen was run in a bomb calorimeter and ΔU was found to be −742.24kJmol−1.The magnitude of ΔH298 for the reaction NH2CN(s)+32(g)→N2(g)+CO2(g)+H2O(l) is ______ kJ. (Rounded off to the nearest integer)
[Assume ideal gases and R=8.314Jmol−1K−1]
Open in App
Solution
NH2CN(s)+32O2(g)→N2(g)+CO2(g)+H2O(l)
∵ΔH=ΔU+ΔngRT
Δng=2−32=0.5
Assume that the ΔU is given at the same temperature. ΔH298=−742.24kJ+0.5×8.314×2981000kJ