Answer:
ΔH = -746.6kJ
Explanation:
Using Hess's law we can find the ΔH of a reaction from the sum of similar reactions. From the reactions:
1. 2CO(g) + O2(g) → 2CO2 ΔH = -566.0kJ
2. N2(g) + O2(g) → 2NO(g) ΔH = 180.6kJ
The negative reaction of 2:
-2. 2NO(g) → N2(g) + O2(g) ΔH = -180.6kJ
The sum of 1 - 2:
2CO(g) + O2(g) + 2NO(g) → 2CO2 N2(g) + O2(g) ΔH = -566.0kJ + (-180.6kJ) =
ΔH = -746.6kJ
Subtracting the molecules that don't change:
2CO(g) + 2NO(g) → 2CO2 + N2(g) ΔH = -746.6kJ
