Problem: Calculate the enthalpy of the reaction2NO(g) + O2(g) → 2NO2(g)Given the following reactions and enthalpies of formation:½ N2(g) + O2(g) → NO2(g) Change in Heat a = 33.2 KJ½ N2(g) + ½ O2 (g) → NO(g) Change in Heat b = 90.2 KJExpress your answer numerically in kilojoules.Change in Heat = ? KJ/mol

FREE Expert Solution

We’re being asked to determine the enthalpy change (ΔHrxn) for the chemical reaction:


2 NO(g) + O2(g)  2 NO2(g)


We can use Hess’s Law to determine the enthalpy change of the overall reaction from the given reactions:

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Problem Details

Calculate the enthalpy of the reaction

2NO(g) + O2(g) → 2NO2(g)

Given the following reactions and enthalpies of formation:

½ N2(g) + O2(g) → NO2(g) Change in Heat a = 33.2 KJ

½ N2(g) + ½ O2 (g) → NO(g) Change in Heat b = 90.2 KJ

Express your answer numerically in kilojoules.

Change in Heat = ? KJ/mol

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