Question

At 25°C and 1 atm pressure, the enthalpy of combustion of benzene (l) and acetylene (g) are \(3268 \, \text{kJ mol}^{-1}\) and \(1300 \, \text{kJ mol}^{-1}\), respectively. The change in enthalpy for the reaction 
is

• A. +324 kJ mol−1
• B. +632 kJ mol−1
• C. −632 kJ mol−1
• D. −732 kJ mol−1

Hint:

Hess’s Law states that the total enthalpy change for a reaction is independent of the pathway taken. The enthalpy change of a reaction can be calculated by summing the enthalpy changes of intermediate reactions.