ØReaction Reversibility:  Species react to produce products.  However, the products can also react to produce the original species. This is known as Òreaction reversibilityÓ.

ØDynamic Equilibrium:  For reversible reactions, both the forward and the reverse reactions are taking place constantly.  If one reaction is taking place more than the other, then the net reaction is in the direction of that reaction. 

All reversible reactions reach a point where the forward and reverse reactions take place at the same rate. This point is called Òdynamic equilibriumÓ.
Useful Terminology