At 298K, the equilibrium constant for the following reaction is 4.20×10^-7:
H2CO3(aq) + H2O -> H3O+(aq) + HCO3-(aq)
The equilibrium constant for a second reaction is 4.80×10^-11:
HCO3-(aq) + H2O -> H3O+(aq) + CO32-(aq)
Use this information to determine the equilibrium constant for the reaction:
H2CO3(aq) + 2H2O -> 2H3O+(aq) + CO32-(aq)