Ka and Pka

[Brynn 2F]

Can someone remind me what the difference between Ka and Pka is?

[Sujin Lim 1H]

Ka is simply the equilibrium constant value for the dissociation of a weak acid in water. You would find this value by taking the equilibrium concentration of the conjugate base of the weak acid multiplied by the equilibrium H3O+ concentration, all divided by the equilibrium concentration of the weak acid. pKa is just the -log of the Ka value, because in chemistry, the "p" essentially stands for "-log".

[jackie-3L]

Ka is the acid dissociation constant and represents the strength of the acid. pKa is the -log of Ka.

pKa + pKb = 14 (pKw)

**The same concept applies for the Kb and pKb**

[Ryan Khiev 1L]

Ka is an equilibrium constant for acidity, with H3O+ and the deprotonated acid, A-, as products, and the acid, HA as a reactant. pKa is simply the negative log of Ka, much like pH is the negative log of hydronium concentration.

[Alison King 3L]

In chemistry whenever there is a "p" before a variable, it means the negative log, so pKa would be the -log(Ka), where Ka is the acid dissociation constant

[BriannaDis2C]

Ka is an acid dissociation constant. It represents an acid’s strength and pKa is the -log of Ka.

[Aashna Bhandari 1L]

The Ka is the acid dissociation constant, which represents the acid's strength. The "p" in front of the Ka in pKa means "-log" so the pKa is the -log(Ka).