When 1.000 g of gaseous butane, C4H10, is burned at 25oC and 1.00 atm pressure, H2O(l) and

Question:

When 1.000 g of gaseous butane, C4H10, is burned at 25oC and 1.00 atm pressure, H2O(l) and CO2(g) are formed with the evolution of 49.50 kJ of heat.
a. Calculate the molar enthalpy of formation of butane. (Use enthalpy of formation data for H2O and CO2.)
b. ∆Gof of butane is 17.2 kJ/mol. What is ∆Go for the combustion of 1 mol butane?
c. From a and b, calculate ∆So for the combustion of 1 mol butane.