The equilibrium condition

In module 7 reaction rate was discussed:

V = k.[conc.]n
Applying this formula to the forward and to the backward reaction
2HI     I2 + H2
we find the following result:

Vforward = kforward x [HI]2
Vbackward = kbackward x [I2] x [H2]

Att.: in principle the concentrations of the substances in an equilibrium never become 0; that means that also the rates never become 0. This may only occur in unidirectional reactions.

The reaction rate is rather dependent on the concentrations of the reacting substances:
The more substrate, the faster the reaction.
  1. at a certain moment there is a maximum rate?
  2. Below you find diagrammes of rates versus concentrations:

The equilibrium condition of a chemical equilibrium is:
The two reaction never become 0 (remain a certain rate) and have equal rates.

Or:      Vforward = Vbackward