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Enthalpy of Formation

Q. Calculate ΔrH in kJ/mol for the following reaction: C6H6(l) +15/2 O2(g) → 6 CO2(g) + 3 H2O(l)

Solved • Apr 16, 2020

Enthalpy of Formation

Q. What is ΔHº rxn (kJ) for the combustion of ethanol. 2 C2H5OH (l) + 6 O2 (g) → 4 CO2 (g) + 6 H2O (l)

Solved • Apr 12, 2020

Enthalpy of Formation

Q. Calculate the standard enthalpy change for reaction 2A + B ⇌ 2C + 2D where the heats of formation are given in the following table Express your answer in kilojoules.

Solved • Apr 9, 2020

Enthalpy of Formation

Q. Given the data in the table below, ΔHorxn for the reaction is; IF5(g) + F2(g) IF7(g) Substance ∆Hof (kJ/mol) IF5(g) -840 IF7(g) -941 A) 1801 kJ B) -1801 kJC) 121 kJ D) -101 kJ

Solved • Apr 12, 2020

Enthalpy of Formation

Q. ∆Ho of the following reaction when 25.0 g of Na2O2 is reacts with water. 2Na2O2(s) + 2H2O(l) 4NaOH(s) + O2(g) DH° = -126 kJ A) -20.2 kJ B) -40.4 kJ C) -67.5 kJ D)-80.8kJ

Solved • Apr 12, 2020

Enthalpy of Formation

Q. Consider the reaction: 4NH3 (g) + 5O2(g)  4NO (g) + 6H2O (g); ΔrH° = -906 kJ/mol 1a) Calculate the energy released when 8 moles of NH3 react completely. (Include the negative sign to indicate heat released) ANSWER: -1812 KJ 1b) Calculate the energy released when 20 g of H2O is formed. (Include the negative sign to indicate heat released) (in KJ) 1c) Calculate the volume of NH3 required at 326 K and 1 atm to produce 495 kJ of heat. (in L) 1d) Calculate the heat released when 15 grams of NH3 (g) reacts with 42 L of O2(g) at 1 atm and 298 K. (Include the negative sign to indicate heat released) (in KJ)

Solved • Apr 9, 2020

Enthalpy of Formation

Q. Write formation reactions for: a) NaCl(s). b) KClO3Also indicate the value of ΔHof for each of the two reactions.

Solved • Apr 5, 2020