The standard heat of formation, Af Hº, 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 Af H° =0. Heat of formation values can be used to calculate the enthalpy change of any reaction. Part A For which of the following reactions is A, H° equal to Af H° of the product(s)? Consider, for example, the reaction You do not need to look up any values to answer this question. 2NO(9) + Oz(9) = 2NO2(9) Check all that apply. with heat of formation values given by the following table: Substance > View Available Hint(s) (kJ mol ) NO(9) O Li(s) + ¿F2(9)→LIF(s) 90.2 02(9) O CaCO3(9)¬CaO + CO2(9) NO2(9) 33.2 O CO(9) + ÷O2(9)→CO2(9) O 2Li(s) + F2(9)→2LIF(s) O (s) + O2(9)→CO2(9) Then the heat of formation for the overall reaction is Δ,Η Σπ, Δι Η ' (prodcts)-ΣnΔι Η' (reactants) = 2(33.2) [2(90.2) + 0] O Li(s) + ¿F2(1)→LIF(s) 114 kJ mol

The standard heat of formation, Af Hº, 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 Af H° =0. Heat of formation values can be used to calculate the enthalpy change of any reaction. Part A For which of the following reactions is A, H° equal to Af H° of the product(s)? Consider, for example, the reaction You do not need to look up any values to answer this question. 2NO(9) + Oz(9) = 2NO2(9) Check all that apply. with heat of formation values given by the following table: Substance > View Available Hint(s) (kJ mol ) NO(9) O Li(s) + ¿F2(9)→LIF(s) 90.2 02(9) O CaCO3(9)¬CaO + CO2(9) NO2(9) 33.2 O CO(9) + ÷O2(9)→CO2(9) O 2Li(s) + F2(9)→2LIF(s) O (s) + O2(9)→CO2(9) Then the heat of formation for the overall reaction is Δ,Η Σπ, Δι Η ' (prodcts)-ΣnΔι Η' (reactants) = 2(33.2) [2(90.2) + 0] O Li(s) + ¿F2(1)→LIF(s) 114 kJ mol

Chemistry: An Atoms First Approach

2nd Edition

ISBN:9781305079243

Author:Steven S. Zumdahl, Susan A. Zumdahl

Publisher:Steven S. Zumdahl, Susan A. Zumdahl

Chapter7: Chemical Energy

Section: Chapter Questions

Problem 76E: Write reactions for which the enthalpy change will be a. Hf for solid aluminum oxide. b. the...

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