Calculate the enthalpy of the reaction 2no(g)+o2(g)→2no2(g) given the following reactions and enthalpies of formation: 12n2(g)+o2(g)→no2(g), δh∘a=33. 2 kj 12n2(g)+12o2(g)→no(g), δh∘b=90. 2 kj.