How do you calculate Ka at equivalence point?

At the equivalence point in a titration, all the acid has reacted with the base, resulting in the formation of the conjugate base of the weak acid or the conjugate acid of the weak base. To calculate the acid dissociation constant (Ka) at this point, you can use the formula ( K_a = \frac{K_w}{K_b} ), where ( K_w ) is the ion product of water and ( K_b ) is the base dissociation constant of the conjugate base formed. This relationship derives from the fact that ( K_a ) and ( K_b ) are related through the ion product of water. Additionally, you may need to know the concentrations of the species present at the equivalence point to apply this relationship accurately.