Calculate the reaction enthalpy of this reaction under standard conditions: 2C2H6(g) + 7O2(g)——> 4CO2(g)+ 6H2O(l) Round your answer to the nearest kJ.

Calculate the standard enthalpy of formation for C3H6O (l) from its combustion using the following data: Enthalpy of this combustion is -1793 kJ ( you must write a balanced reaction first).

Use Hess’s law to calculate the enthalpy change for the reaction WO3(s) + 3H2(g) —> W(s) +3H2O(g) from the following data: 2W(s) + 3O2(g) —> 2 WO3(s) H=-1685.4 2H2(g) + O2(g) —> 2H2O(g) H=-477.84

Using the standard enthalpies of formation, what is the standard enthalpy of reaction? CO(g) + H,O(g) –→ CO,(g) + H,(g) AHân = kJ

to calculate the true enthalpies of these reactions by the Hess’ law, as: ΔH°(rxn) = Σ[ν × ΔHf°(product)] – Σ[ν × ΔHf°(reactant)] for: Mg(s) + ½O2(g) → MgO(s)

Find the enthalpy change for this reaction using the data below. Clearly show how you got the answer. 2 Al(s) + 3 Cl2 (g) → 2 AlCl3 (s) Data: (a) 2 Al(s) + 6 HCl(aq) → 2 AlCl3 (aq) + 3 H2 (g)                     H = −1049 kJ (b) AlCl3 (s) → AlCl3 (aq)                                                             H = −323 kJ (c) H2 (g) + Cl2 (g) → 2 HCl(g)                                                    H = −185 kJ (d) HCl(aq) → HCl(g)                                                                     H = +74.8 kJ

（1）Consider the reaction: 2A (g) + 3 B (g) → 2 C (g)     ΔHrxn = +254.3 kJ What will be the enthalpy change (in kJ) if 0.471 mol B reacts in excess A?   （2）Consider the reaction: C (s) + O2 (g) → CO2 (g)     ΔHrxn = -393.5 kJ What mass of carbon (in g) must be reacted via this mechanism to release 581.2 kJ of heat?