Propane (c3 h8 (g), hf = –103.8 kj/mol) reacts with oxygen to produce carbon dioxide (co2 , hf = –393.5 kj/mol ) and water (h2 o, hf = –241.82 kj/mol) according to the equation below. what is the enthalpy of combustion (per mole) of c3 h8 (g)? use . –2,044.0 kj/mol –531.5 kj/mol 531.5 kj/mol 2,044.0 kj/mol

Given:

Enthalpy of formation data

Hf(C3H8) = -103.8 KJ/Mol

Hf(CO2) = -393.5 kJ/mol

Hf (H2O) = -241.82 kJ/mol

To determine:

Enthalpy of combustion of C3H8

Explanation:

The combustion reaction is:

C3H8 + 5O2 → 3CO2 + 4H2O

ΔHcombustion = ∑nHf(products) - ∑nHf(reactants)

ΔHc = [3(Hf CO2) + 4(Hf H2O)] - [Hf(C3H8) + 5Hf(O2)]

       = [3(-393.5) + 4(-241.82)] -[-103.8 + 5(0)] = -2044 kJ/mol

Ans: (a) -2044 kJ/mol