The reactant-product equilibrium

In this reaction a reactant A is in equilibrium with a product X A X (6.14) 

A kinetic equation, provided that [A] is maintained at a constant level, is of the form (where x — [X], a = [A])  

The stationary state for kinetic equation (6.15) is given by (see equation (5.4)) 

Equation (6.15) is linear, thus substitution (5.5) leading to the equation 

the stationary state (6.16) is always stable and in the system represented by kinetic equation (6.15) catastrophes cannot occur. 

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