pH and pKa

[Allan Nguyen 2G]

I know that they're both different, but how can I differentiate between the two in terms of application and concepts?

[Kaley Qin 1F]

It just depends on what the question is asking. If it asks for equilibrium or a constant, use pKa. If it asks for a concentration or anything related to concentration use pH.

[Katie Nye 2F]

Both refer to acids and bases but pKa is specifically related to dissociation and how much the substance will dissociate in water while pH is simply the acidity of the substance.

[Aishwarya Kosgi 1F]

Hi! Adding on to this question, is pH associated with strong acids/bases and is pKa associated with weak acids/bases? I think I remember learning that if a reaction has a Ka/Kb value, that means it is a weak acid/base. If anyone could clarify, that would be great! Thanks!

[BrittneyMyint1D]

Hi, I believe that pH would be more used for showing the concentration of H3O+ since pH is gotten from -log[H3O+] while pKa is more related to dissociation of the acid since it's gotten from -log(Ka). It may also depend on the information given and what the question is asking. Hope this helps!

[Pranav Daggubati 3C]

An easy way to think about it would be to think of p as a modifier that states the relative amount of things that are released. pH is then a measure of the number of H3O+ ions that are created when something dissolves. pKa would be the measure of the relative number of disassociations that happen when and acid is dissolved.

[Mary Shih 3J]

PH= tells us how acidic something is (can indirectly tell you how basic it is also)
Pka= dissociation of acid or base