Use the standard reaction enthalpies given below to determine ΔH°_rxn for the following reaction: 2 NO(g) + O₂(g) → 2 NO₂(g) ΔH°_rxn= ?
Given:
N₂(g) + O₂(g) → 2 NO(g) ΔH°_rxn= +183 kJ
1/2 N₂(g) + O₂(g) → NO₂(g) ΔH°_rxn= +33 kJ

Question

Quizplus · Accepted Answer

To find ΔH°_rxn for 2 NO(g) + O₂(g) → 2 NO₂(g), reverse the first reaction and double the second reaction, then add them: Reverse: 2 NO(g) → N₂(g) + O₂(g), ΔH° = -183 kJ Double: N₂(g) + 2 O₂(g) → 2 NO₂(g), ΔH° = 2(33 kJ) = +66 kJ Add: 2 NO(g) + O₂(g) → 2 NO₂(g), ΔH° = -183 kJ + 66 kJ = -117 kJ.

Use the Standard Reaction Enthalpies Given Below to Determine ΔH°rxn

Use the Standard Reaction Enthalpies Given Below to Determine ΔH°_rxn