Part A. Calculate the enthalpy of the reaction
2NO(g) + O2(g) → 2NO2(g)
Given the following reactions and enthalpies of formation:
1. 1/2 N2(g) + O2(g) → NO2(g), ΔH°A = 33.2 kJ
2. 1/2 N2(g) + 1/2 O2(g) → NO(g), ΔH°B = 90.2 kJ
Express your answer with the appropriate units.
Hess's law states that "the heat released or absorbed in a chemical process is the same whether the process takes place in one or in several steps." It is important to recall the following rules:
1. When two reactions are added, their enthalpy values are added.
2. When a reaction is reversed, the sign of its enthalpy value changes.
3. When the coefficients of a reaction are multiplied by a factor, the enthalpy value is multiplied by that same factor.
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