Butane (C4H10(g), deltaHf =-125.6 kJ/mol reacts with oxygen to produce carbon dioxide (CO2 delta Hf =-393.5 kJ/mol)

The given question is incomplete. The complete question is:

Butane , Hf = –125.6 kJ/mol) reacts with oxygen to produce carbon dioxide ( , Hf = –393.5 kJ/mol ) and water , Hf = –241.82 kJ/mol) according to the equation below. What is the enthalpy of combustion (per mole) of ?

-2657.5 kJ

Explanation:

The balanced chemical reaction is,

The expression for enthalpy change is,

where,

n = number of moles

(as heat of formation of substances in their standard state is zero

Now put all the given values in this expression, we get

Therefore, the enthalpy of combustion per mole of butane is -2657.5 kJ