## Standard Enthalpy of Reaction**Learning Goal:**To understand how the standard enthalpy of reaction is related to the standard heats of formation of the reactants and products.The standard enthalpy of reaction is the enthalpy change that occurs in a reaction when all the reactants and products are in their standard states. The symbol for the standard enthalpy of reaction is ΔH⁰_rxn, where the subscript "rxn" stands for "reaction." The standard enthalpy of a reaction is calculated from the standard heats of formation (ΔH⁰_f) (subscript “f” for "formation") of its reactants and products. Therefore, the standard enthalpy ΔH⁰_rxn of any reaction can be mathematically determined, as long as the standard heats of formation (ΔH⁰_f) of its reactants and products are known.**Exercise:**What is ΔH_rxn for the following chemical reaction?\[ \text{H}_2\text{O}(\text{l}) + \text{CCl}_4(\text{l}) \rightarrow \text{COCl}_2(\text{g}) + 2\text{HCl}(\text{g}) \]To solve this problem, you can use the following table of standard heats of formation (ΔH⁰_f) to calculate the enthalpy of the given reaction.| Element/Compound | Standard Heat of Formation (kJ/mol) | Element/Compound | Standard Heat of Formation (kJ/mol) ||:----------------:|:----------------------------------:|:----------------:|:----------------------------------:|| H(g) | 218 | N(g) | 473 || H₂(g) | 0 | O₂(g) | 249 || CCl₄(l) | -139.5 | HCl(g) | -92.3 || H₂O(l) | -285.8 | COCl₂(g) | -218.8 || Cl₂(g) | 71 | HNO₃(aq) | -206.6 || C(s) | 0 | | |**Task:**Express the standard enthalpy of reaction to three significant figures and include the appropriate units.

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What is AHan for the following chemical reaction? H20(1) + CC4 (1)-→COCl2(g) + 2HC1(g) You can use the fllowing table of standard heats of formation (AH) to calculate the enthalpy of the given reaction. Standard Heat of Formation (kJ/mol) Standard Heat of Element/ Compound Element/ Compound Formation (kJ/mol) H(g) 218 N(g) 473 H2(g) O2(g) 249 CL (1) H2O(1) 139.5 O(g) 285.8 HCI(g) -92.30kJ COC (g) -218.8kJ C(g) 71 C(s) HNO:(aq) 206.6 Express the standard enthalpy of reaction to three significant figures and include the appropriate units. • View Available Hint(s) HA Value Units Submit Previous Answers

What is AHan for the following chemical reaction? H20(1) + CC4 (1)-→COCl2(g) + 2HC1(g) You can use the fllowing table of standard heats of formation (AH) to calculate the enthalpy of the given reaction. Standard Heat of Formation (kJ/mol) Standard Heat of Element/ Compound Element/ Compound Formation (kJ/mol) H(g) 218 N(g) 473 H2(g) O2(g) 249 CL (1) H2O(1) 139.5 O(g) 285.8 HCI(g) -92.30kJ COC (g) -218.8kJ C(g) 71 C(s) HNO:(aq) 206.6 Express the standard enthalpy of reaction to three significant figures and include the appropriate units. • View Available Hint(s) HA Value Units Submit Previous Answers

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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