seesaw

[Geoffrey Yang 3E]

What is the reasoning behind the conjugate seesaw, like why is the conjugate base of a strong acid weak?

[105907609]

The conjugate seesaw is related to the strength of acids and base, Bronsted-Lowry theory of acids and bases, an acid is a substance that can donate a proton, and a base can accept a proton. The strength of an acid is inversely related to the strength of its conjugate base, and vice versa. Strong acids have weak conjugate bases, and weak acids have strong conjugate bases. This relationship is often explained using the equilibrium constant (K_a) for acid dissociation. For a strong acid, the equilibrium lies far to the right, meaning that the acid readily donates its proton, resulting in a high concentration of hydronium ions (H3O+) in solution. On the other hand, weak acids only partially dissociate in water, so the equilibrium lies to the left. Their conjugate bases are stronger because they are more willing to accept protons in the reverse reaction. Hope this helps

[Maria George 3K]

Strong acids are said to go to completion, which means that the reverse reaction happens at a very low rate. So the Ka for a strong acid is quite large, but the K value for the reverse reaction (Kb for the conjugate base) is very low. The conjugate base and proton that the strong acid dissociates into is unlikely to form back into the acid. So the acid has a large Ka and small Kb, which contributes to the "seesaw" effect.