The balanced chemical reaction here is:
C3H8(g) + 5O2(g) --> 3CO2(g) + 4H2O(l)
Calculating for the molar change in enthalpy:
Enthalpy change = 3(-393.5) + 4(-285.83) -
(-103.85) = -2220.0 kJ/mole
Now, propane has a molar mass of 44g/mol. So, for
us to calculate the heat released by burning 14 grams of propane, we have:
-2220 kJ/mole * ( 14g / 44g/mol) = -706.36 kJ
Answer:
-706.36 kJ
(negative means heat is released)
