Hi, thank you for reading my question.
In some references, I have seen a phrase like "basic pKa" or "pKa for a base".
Example reference:
https://jcheminf.biomedcentral.com/track/pdf/10.1186/s13321-019-0384-1.pdf
pKa is defined for acids. I was wondering what "basic pKa" means?
I am aware of the relationship between pKa & pKb:
pKa * pKb = pKw
Is "basic pKa" the same as pKb?
Mohammad Saber
The pKa value is one way for determining an acid's strength. The negative log of the acid dissociation constant, or Ka value, is pKa. A lower pKa value denotes a more potent acid. That example, a lower number implies that the acid dissociates more completely in water.
The pKa and pKb values are used to compare the acid and base strengths. For acid dissociations, pKa is specified. For base dissociation, pKb is specified. pKa and pKb vary in that pKa is the negative logarithm of Ka, whereas pKb is the negative logarithm of Kb.
The negative log of the dissociation constant Ka is PKa.The pKa of a base is the pKa of the conjugate acid of that base.
i) pKa >7 to 11 is for a weak base
ii) pKa >11 is for a strong base
• A molecule containing ionizing groups with both acidic and basic pKa values is called an ampholyte. • The ionic form of each group in the compound is dependent on the pH of the solution
Is "basic pKa" the same as pKb?. No!
"Basic pKa" refers to that pKa value that comes from a basic group such as an amino group. In other words, basic pKa refers to processes where an atom is protonated to form a positive charge.
"Acidic pKa" refers to that pKa value that comes from an acidic group such as a carboxylic acid group. In other words, acidic pKa refers to processes where an atom loses a hydrogen and forms a negative charge.
Note: Do not confuse with the terms: "pka acid" values or "pka basic" values.
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