Classification of Penicillin. 1  Natural Penicillins (Penicillin V, Penicillin G, Benzathine, Procaine Penicillin) 2  Penicillinase-Resistant Penicillins (Oxacillin, Dicloxacillin, Cloxacillin, Methicillin, Nafcillin) 3  Aminopenicillins (Amoxicillin, Bacampicillin, Ampicillin) 4  Extended Spectrum Penicillins.
the system is usually defined as the chemical reaction and the boundary is the container in which the reaction is run in the course of the reaction heat is either given off or absorbed by the system furthermore the system either does work on it surroundings or has work done on it by its surroundings
Chemical equilibrium is a very delicate system that represents a perfect balance between forward and reverse reaction. A small disturb in the equilibrium may shift the equilibrium position either to right forming more products or to left forming more reactants. This reaction by the system is of course temporary and eventually the system will come back to equilibrium.