What two conditions must be met by a thermochemical equation so that its enthalpy change can be given the symbolA H;? O The reaction must consume one mole of reactants at 25°C and 1 bar. O The reactants must be elements in their standard states. O The reaction must produce one mole of product at 25°C and 1 bar. O The products must be elements in their standard states.

What two conditions must be met by a thermochemical equation so that its enthalpy change can be given the symbolA H;? O The reaction must consume one mole of reactants at 25°C and 1 bar. O The reactants must be elements in their standard states. O The reaction must produce one mole of product at 25°C and 1 bar. O The products must be elements in their standard states.

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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The standard heat of formation, AH, is defined as the enthalpy change for the formation of one mole of substance from its constituent elements in their standard states. Thus, elements in their standard states have AH = 0. Heat of formation values can be used to calculate the enthalpy change of any reaction. Consider, for example, the reaction 2NO(g) + O2(g) = 2NO₂(g) with heat of formation values given by the following table: Substance ΔΗ (kJ/mol) 90.2 0 33.2 NO(g) O₂(g) NO₂(g) Then the standard heat of reaction for the overall reaction is AH AH (products) AH; (reactants) [2(90.2) +0] = 2(33.2) = -114 kJ Part A For which of the following reactions is AHn equal to AH; of the product(s)? You do not need to look up any values to answer this question. Check all that apply. ► View Available Hint(s) Li(s) + Cl₂(g) →LiCl(s) SO(g) + O₂(g) →SO2(g) S(s) + O₂(g) →SO₂ (g) SO3(g) → O₂(g) + SO2(g) Li(s) + Cl₂(1)→LiCl(s) 2Li(s) + Cl₂ (g)→2LiCl(s) Submit Constants I Periodic Table Part B
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