# Homework Help: {Thermochemistry} Hess' law problem

1. Feb 7, 2010

### hiuting

1. The problem statement, all variables and given/known data
Benzene (C6H6) is a liquid which burns in air to form liquid water and carbon dioxide. Calculate the heat released by burning one gram of benzene.

$$\Delta$$Hof, kJ/mol
carbon dioxide (g) = -393.5
water (l) = -285.8
benzene (l) = 49.04

2. Relevant equations
2C6H6 (l) + O2 (g) >> 12 CO2 (g) + 6 H2O (l)

3. The attempt at a solution

I got -25.42 kJ ... do I have to find the amount of moles in 1 gram of benzene first? and then do the calculations?