pKa/pKb and Ka/Kb

Posts: 50
Joined: Tue Nov 05, 2019 12:18 am

pKa/pKb and Ka/Kb

What is the difference between pKa/pKb and Ka/Kb?

Amanda Lin 2I
Posts: 101
Joined: Sat Aug 17, 2019 12:15 am

Re: pKa/pKb and Ka/Kb

Ka is the acid dissociation constant. Kb is the base dissociation constant.

pKa = -log(Ka)
pKb = -log(Kb)

Connor Chappell 2B
Posts: 59
Joined: Wed Feb 20, 2019 12:16 am

Re: pKa/pKb and Ka/Kb

Ka is the acidity constant, and Kb is the basicity constant.

pKa = -log(Ka)
pKb = -log(Kb)

Jasmine Kim 1L
Posts: 71
Joined: Fri Aug 02, 2019 12:16 am

Re: pKa/pKb and Ka/Kb

The p before Ka and Kb just shows that it is the -log value of Ka and Kb, like how pH and pOH means -log[H3O+] and -log[OH-]

Kallista McCarty 1C
Posts: 212
Joined: Wed Sep 18, 2019 12:18 am

Re: pKa/pKb and Ka/Kb

Ka = 10^-pKa
Kb = 10^-pKb

Jialun Chen 4F
Posts: 108
Joined: Sat Sep 07, 2019 12:16 am

Re: pKa/pKb and Ka/Kb

The relationship is analogous to that of pH/pOH and [H3O+]/[OH-].
Essentially,
10^-pKa=Ka (same applies for Kb)
pKa=-log(Ka) (same applies for Kb).