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Name Block Date Hess' Law WS (Honors) Hess' Law can be used in a number of ways to calculate heat exchange

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Name Block Date Hess' Law WS (Honors) Hess' Law can be used in a number of ways to calculate heat exchange. The two most common methods to utilize data will be reaction rearrangement and summation of heats of formation. You will practice each method. Part I: Calculate the AH given the following data: = 1. Given the following enthalpy data: C(s) + O2(g) CO2(g) H2(g) + 1/2O2 (g) H2O(1) C2H2(g) + 5/202(g) H2O (g) + 2CO2 (g) Use Hess's law to calculate AH for the reaction: 2C(s) + H2(g) - → C2H2(g) AH - 393.5 kJ AH - 285.8 kJ AH -1301.0 kJ = ΔΗ 2. Given the following enthalpy data: H2(g) + F2 (g) → 2HF (g) C(s) + 2F2 (g) → CF4 (g) 2C (s) + 2H2 (g) C2H4 (g) Use Hess's law to calculate AH for the reaction: C2H4(g) + 6F2 (g) 2CF4 (g) + 4HF(g) AH 537kJ AH - 680 kJ AH : +52.3 kJ = AH 8+ ••• Part II: Use Hess’ Law to calculate the enthalpy of reaction, AH,xn using the summation method of heats of formation. Formula: AH,xn = EAH, (products) - EAH, (reactants) 3. Given the following data, calculate heat of reaction, AH,x rxn Fe2O3(s) + 3CO(g) + 2Fe(s) + 3CO2(g) Substance Fe2O3(s) CO(g) Fe(s) CO2(g) AH (kJ/mol) -824.8 -110.5 0 -393.5 4. Given the following data, calculate boat afronation au 7XIT 4. Given the following data, calculate heat of reaction, AH,xn 702(g) + 4NH3(g) → 2N204(g) + 6H2O(1) Substance O2(g) NH3(g) NO2(g) H2O(1) AH, (kJ/mol) 0 -45.9 +9.1 -285.8