pKb to pKa
Type a value in pKb to get it in pKa instantly.
9.24pKa
That's 776× as weak as carbonic acid, while the ammonium ion is 1.02× weaker. That is a weak acid, useful as a buffer near this pH.
Convert the other way: pKa to pKb
What it means
How strong is that acid?
Values are for water at 25 °C. pKa shifts with solvent and temperature, and in a protein an ordinary side chain can move several units.
The math
How to convert pKb to pKa
pKa is a logarithm: pKa = −log₁₀(Ka), and back again Ka = 10^(−pKa). In water at 25 °C, pKa + pKb = 14, and the free energy is ΔG° = 5.708 × pKa kJ/mol.
Example: 4.76 pKb = 9.24 pKa.
Every unit
Your acid strength in every unit
Tables
pKb to pKa conversion table
| pKb | pKa |
|---|---|
| -10 pKb | 24 pKa |
| -7 pKb | 21 pKa |
| -3 pKb | 17 pKa |
| 0 pKb | 14 pKa |
| 2 pKb | 12 pKa |
| 3.75 pKb | 10.25 pKa |
| 4.76 pKb | 9.24 pKa |
| 6.35 pKb | 7.65 pKa |
| 7.2 pKb | 6.8 pKa |
| 9.25 pKb | 4.75 pKa |
| 10.3 pKb | 3.7 pKa |
| 14 pKb | 0 pKa |
| 16 pKb | -2 pKa |
pKa to pKb conversion table
| pKa | pKb |
|---|---|
| -10 pKa | 24 pKb |
| -7 pKa | 21 pKb |
| -3 pKa | 17 pKb |
| 0 pKa | 14 pKb |
| 2 pKa | 12 pKb |
| 3.75 pKa | 10.25 pKb |
| 4.76 pKa | 9.24 pKb |
| 6.35 pKa | 7.65 pKb |
| 7.2 pKa | 6.8 pKb |
| 9.25 pKa | 4.75 pKb |
| 10.3 pKa | 3.7 pKb |
| 14 pKa | 0 pKb |
| 16 pKa | -2 pKb |
Quick answers
Quick answers
- How many pKa is 1 pKb?
- 1 pKb is 13 pKa.
- How many pKa is 10 pKb?
- 10 pKb is 4 pKa.
- How many pKa is 4.76 pKb?
- 4.76 pKb is 9.24 pKa.
The units
About these units
pKb (pKb)
The same for the conjugate base. pKa and pKb always add to 14 in water.
pKa (pKa)
The negative logarithm of the dissociation constant. Lower means stronger.
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