<P> where k is a temperature - dependent constant, p is the partial pressure and c is the concentration of the dissolved gas in the liquid Thus the partial pressure of CO in the gas has increased until Henry's law is obeyed . The concentration of carbon dioxide in the liquid has decreased and the drink has lost some of its fizz . </P> <P> Henry's law may be derived by setting the chemical potentials of carbon dioxide in the two phases to be equal to each other . Equality of chemical potential defines chemical equilibrium . Other constants for dynamic equilibrium involving phase changes, include partition coefficient and solubility product . Raoult's law defines the equilibrium vapor pressure of an ideal solution </P> <P> Dynamic equilibrium can also exist in a single - phase system . A simple example occurs with acid - base equilibrium such as the dissociation of acetic acid, in aqueous solution . </P> <Dl> <Dd> CH CO H ⇌ (\ displaystyle \ rightleftharpoons) CH CO + H </Dd> </Dl>

When does the given chemical system reach dynamic equilibrium