Dissociation Constant
| Formula / Notation | Ka = [H⁺][A⁻]/[HA]; pKa = −log Ka; Kd (dissociation constant) |
|---|---|
| Also Known As | Ka, Kb, Kd, acid dissociation constant, ionisation constant, binding constant |
What is Dissociation Constant?
An equilibrium constant that quantifies the tendency of a complex or molecule to dissociate into its component parts. For acids, Ka represents the dissociation constant in water. Larger Ka values indicate stronger acids that dissociate more completely.
Formula & Notation
Other Names / Synonyms: Ka, Kb, Kd, acid dissociation constant, ionisation constant, binding constant
Properties & Characteristics
Uses & Applications
Safety Information
Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.
Key Facts
Frequently Asked Questions
An equilibrium constant that quantifies the tendency of a complex or molecule to dissociate into its component parts. For acids, Ka represents the dissociation constant in water. Larger Ka values indicate stronger acids that dissociate more completely.
Dissociation constants are fundamental in acid-base chemistry, buffer design, pharmacology (drug-receptor binding affinity), biochemistry (enzyme-substrate Km in Michaelis-Menten kinetics), and analytical chemistry (predicting speciation in titrations and chromatographic separations).
Low pKa (strong acid with high Ka) indicates a compound that can quickly lower pH to dangerous levels. High Ka values mean even dilute solutions are significantly acidic. Always calculate the expected pH of solutions before preparation and use appropriate corrosion protection.
The formula or notation for Dissociation Constant is: Ka = [H⁺][A⁻]/[HA]; pKa = −log Ka; Kd (dissociation constant)