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- Apr 2, 2013
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In BR O Chem Chapter 1, enthalpy is discussed and the equation [delta H = The sum (Energy of bonds broken - Energy of bonds formed)] is given.
The equation seems incorrect to me and I think formed and broken should be switched.
If the bonds formed (the bonds in the product) have more energy than those broken in the reactants, then there would have to be a net input of energy into the reaction, and the reaction would be endothermic. However, numbers like that would give a negative number for enthalpy, which is exothermic.
It might be the way it's stated, because I get Hf-Hi = delta H. I take that to mean that the sum of the energy of all the bonds at the end of the reaction minus the sum of the energy of all the bonds before the reaction is the change in enthalpy.
Am I just looking at this in a wrong way?
It's been bugging me for over a week.
I greatly appreciate any help!!!
The equation seems incorrect to me and I think formed and broken should be switched.
If the bonds formed (the bonds in the product) have more energy than those broken in the reactants, then there would have to be a net input of energy into the reaction, and the reaction would be endothermic. However, numbers like that would give a negative number for enthalpy, which is exothermic.
It might be the way it's stated, because I get Hf-Hi = delta H. I take that to mean that the sum of the energy of all the bonds at the end of the reaction minus the sum of the energy of all the bonds before the reaction is the change in enthalpy.
Am I just looking at this in a wrong way?
It's been bugging me for over a week.
I greatly appreciate any help!!!