Change in pH of a solution

[Aprice_1J]

Why do some molecules have a stronger affect on pH than others? I know that all conjugate bases of a strong acid do not change the pH (from lecture on 12/2) but why is this and does it have to do with how much hydroxide or hydronium is produced and the amount of dissociation?

[Brian_Ho_2B]

Why do some molecules have a stronger affect on pH than others? I know that all conjugate bases of a strong acid do not change the pH (from lecture on 12/2) but why is this and does it have to do with how much hydroxide or hydronium is produced and the amount of dissociation?

Conjugate bases of strong acids are very stable and do not affect the amount of hydronium or hydroxide ions. However, conjugates of weak acids/bases may affect hydronium or hydroxide concentrations (b/c they can act as acids/bases), which are used to calculate pH and pOH. Recall pH= -log[H3O+]

[Mallika Chimpiri 3K]

This is because depending on the molecule, conjugates of it may affect the concentration of hydroxide and hydronium ions, which affects the pH.