What is the standard enthalpy change of combustion of ethane?

1 Answer
Dec 31, 2016

Answer:

Got me..........

Explanation:

The standard enthalpy of combustion is the enthalpy associated with the combustion of one mole of substance under standard conditions. And thus for ethane it is the enthalpy associated with the following reaction:

#C_2H_6 (g)+ 7/2O_2(g) rarr 2CO_2(g) + 3H_2O(l)+Delta#

My old notes say #DeltaH_"combustion"^@=-1560*kJ*mol^-1#

But how can I have a negative energy?