The equilibrium concentrations of H+ and CH3 COO- have to be determined given the initial concentration and final concentration of the weak acid, CH3 COOH.
is a weak acid which partially ionizes in solution. The products of ionization, CH3 COO- and H+ exist in equilibrium with the weak acid. The change in concentration of the weak acid when the system reaches equilibrium will be equal to the concentration of the ionization products.
The equilibrium reaction representing the ionization of weak acid, is,
The initial concentration of the acid = 0.10 M.
Concentration of acid at equilibrium = 0.098 M.
Change in concentration of
This change in concentration of CH3 COOH will be equal to the concentration of and formed during the ionization of CH3 COOH.
The expected equilibrium constant for the above reaction has to be calculated.
Equilibrium constant is the ratio of the concentrations of products to the reactants concentrations, each term raised to the power equal to the stoichiometric coefficient.
The expected equilibrium constant for the reaction is .
The given equilibrium ionization reaction is,
Plugging in the equilibrium concentrations to calculate the K value,