How much heat is exchanged by this system?

I am having trouble with the following question:


We allow $\pu{18 g}$ of oxygen to react with $\pu{23 g}$ of ethane. The reaction is shown below. Since the heat of combustion of ethane is $\pu{-1560 kJ mol-1}$, how much heat is exchanged by the system if the reaction is the system?
$$\ce{C2H6 (g) + 7/2 O2 (g) -> 2 CO2 (g) + 3 H2O (g)}$$
express $q$ in $\pu{kJ}$.


The answer I keep getting is $\pu{1193 kJ}$ because $\frac{23}{30.07} \times (-1560)$ would be $-1193$ and we are meant to express heat as being positive so it would finally be 1193. This is wrong apparently. What am I doing wrong?


