Given the following data
N2(g) + 2O2(g) ---> 2NO2(g) Δ H = 67.7 kJ
N2(g) + 2O2(g) ---> N2O4(g) Δ H = 9.7 kJ
Calculate Δ H for the dimerization of NO2: 2NO2(g) ---> N2O4
The answer is -58.0 kJ
Any help at all would be greatly appreciated, I have been stumped on this for a long long time!
N2(g) + 2O2(g) ---> 2NO2(g) Δ H = 67.7 kJ
N2(g) + 2O2(g) ---> N2O4(g) Δ H = 9.7 kJ
Calculate Δ H for the dimerization of NO2: 2NO2(g) ---> N2O4
The answer is -58.0 kJ
Any help at all would be greatly appreciated, I have been stumped on this for a long long time!
-
Flip the first equation and leave the second one alone. The result:
2NO2(g) ---> N2(g) + 2O2(g) Δ H = -67.7 kJ
N2(g) + 2O2(g) ---> N2O4(g) Δ H = 9.7 kJ
When you add the two equations, the N2 and the 2O2 cancel, leaving you with your target equation.
When we add equations, we add their enthalpies:
-67.7 + 9.7 = -58.0 kJ
More like this:
http://www.chemteam.info/Thermochem/Hess…
2NO2(g) ---> N2(g) + 2O2(g) Δ H = -67.7 kJ
N2(g) + 2O2(g) ---> N2O4(g) Δ H = 9.7 kJ
When you add the two equations, the N2 and the 2O2 cancel, leaving you with your target equation.
When we add equations, we add their enthalpies:
-67.7 + 9.7 = -58.0 kJ
More like this:
http://www.chemteam.info/Thermochem/Hess…