**Chemical Reaction and Heat Exchange Analysis** Consider the reaction: \[ 2 \text{Fe}_2\text{O}_3 \rightarrow 4 \text{Fe} + 3 \text{O}_2 \] \[ \Delta H^\circ_{\text{rxn}} = +824.2 \, \text{kJ} \] The decomposition of 79.0 g of Fe₂O₃ results in: - ○ the release of 32600 kJ of heat. - ○ the absorption of 204 kJ of heat. - ○ the release of 204 kJ of heat. - ○ the absorption of 408 kJ of heat. - ○ the absorption of 32600 kJ of heat. - ○ the release of 408 kJ of heat. **Analysis of ΔH (Enthalpy Change):** - The positive ΔH value indicates an endothermic reaction, meaning that the reaction absorbs heat. **Educational Explanation:** - To find the heat change for the decomposition of 79.0 g of Fe₂O₃, the molar mass of Fe₂O₃ should be used to convert the grams to moles. The stoichiometry of the balanced equation and the given ΔH can then be used to determine the heat absorbed or released for this specific mass of Fe₂O₃.

Chemical Reaction and Heat Exchange Analysis Consider the reaction: \[ 2 \text{Fe}_2\text{O}_3 \rightarrow 4 \text{Fe} + 3 \text{O}_2 \] \[ \Delta H^\circ_{\text{rxn}} = +824.2 \, \text{kJ} \] The decomposition of 79.0 g of Fe₂O₃ results in: - ○ the release of 32600 kJ of heat. - ○ the absorption of 204 kJ of heat. - ○ the release of 204 kJ of heat. - ○ the absorption of 408 kJ of heat. - ○ the absorption of 32600 kJ of heat. - ○ the release of 408 kJ of heat. Analysis of ΔH (Enthalpy Change): - The positive ΔH value indicates an endothermic reaction, meaning that the reaction absorbs heat. Educational Explanation: - To find the heat change for the decomposition of 79.0 g of Fe₂O₃, the molar mass of Fe₂O₃ should be used to convert the grams to moles. The stoichiometry of the balanced equation and the given ΔH can then be used to determine the heat absorbed or released for this specific mass of Fe₂O₃.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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