The brand new magnitude of the equilibrium constant getting an ionization reaction can be employed to influence the cousin importance away from acids and you may basics. Such as for instance, the entire equation towards ionization regarding a faltering acidic for the liquid, in which HA is the mother or father acid and you may A good? is actually their conjugate ft, can be follows:
As we noted earlier, the concentration of water is essentially constant for all reactions in aqueous solution, so \([H_2O]\) in Equation \(\ref<16.5.2>\) can be incorporated into a new quantity, the acid ionization constant (\(K_a\)), also called the acid dissociation constant:
You will find an easy matchmaking involving the magnitude away from \(K_a\) for an acid and you can \(K_b\) for its conjugate feet
Thus the numerical values of K and \(K_a\) differ by the concentration of water (55.3 M). Again, for simplicity Japanese dating sites, \(H_3O^+\) can be written as \(H^+\) in Equation \(\ref<16.5.3>\). Keep in mind, though, that free \(H^+\) does not exist in aqueous solutions and that a proton is transferred to \(H_2O\) in all acid ionization reactions to form hydronium ions, \(H_3O^+\). The larger the \(K_a\), the stronger the acid and the higher the \(H^+\) concentration at equilibrium. (mais…)