In a chemical
reaction
DH = H products – H reactants
![](slide0006_image011.png)
If DH >0, then qp >0
The reaction is Endothermic.
Heat goes from the surroundings
into the system.
If DH <0, then qp <0
The reaction is Exothermic.
Heat goes from the system into the surroundings.
An example of an exothermic
reaction:
An example from the S&T mining
dept: