Find Δ H rxn for the following reaction: N 2 + 2 O 2 → 2 NO 2 Based on the following data. 2 NO → N 2 + O 2 Δ H = −180 kJ 2 NO + O 2 → 2 NO 2 Δ H = −112 kJ

Identify the target reaction: N 2 + 2 O 2 → 2 NO 2 . We need to find the enthalpy change (ΔH rxn ) for this reaction.. Examine the given reactions and their enthalpy changes: 1) 2 NO → N 2 + O 2 with ΔH = -180 kJ, and 2) 2 NO + O 2 → 2 NO 2 with ΔH = -112 kJ.. Reverse the first reaction to match the formation of NO from N 2 and O 2 : N 2 + O 2 → 2 NO. This changes the sign of ΔH to +180 kJ.. Add the reversed first reaction to the second reaction: (N 2 + O 2 → 2 NO) + (2 NO + O 2 → 2 NO 2 ). This results in the target reaction: N 2 + 2 O 2 → 2 NO 2 .. Calculate the overall ΔH rxn by summing the enthalpy changes of the modified reactions: ΔH = (+180 kJ) + (-112 kJ).

8. Thermochemistry

Enthalpy of Formation

General Chemistry

8. Thermochemistry

Enthalpy of Formation

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Multiple Choice

Find ΔH_rxn for the following reaction:
N₂ + 2 O₂ → 2 NO₂
Based on the following data.
2 NO → N₂ + O₂ ΔH = −180 kJ
2 NO + O₂ → 2 NO₂ ΔH = −112 kJ

68 kJ

−68 kJ

−292

292

−146

Verified step by step guidance

Identify the target reaction: N₂ + 2 O₂ → 2 NO₂. We need to find the enthalpy change (ΔH_rxn) for this reaction.

Examine the given reactions and their enthalpy changes: 1) 2 NO → N₂ + O₂ with ΔH = -180 kJ, and 2) 2 NO + O₂ → 2 NO₂ with ΔH = -112 kJ.

Reverse the first reaction to match the formation of NO from N₂ and O₂: N₂ + O₂ → 2 NO. This changes the sign of ΔH to +180 kJ.

Add the reversed first reaction to the second reaction: (N₂ + O₂ → 2 NO) + (2 NO + O₂ → 2 NO₂). This results in the target reaction: N₂ + 2 O₂ → 2 NO₂.

Calculate the overall ΔH_rxn by summing the enthalpy changes of the modified reactions: ΔH = (+180 kJ) + (-112 kJ).