dissociation constant

The dissociation constant (Kₐ) measures how easily a compound, such as an acid or a ligand, breaks apart into its ions or components in solution. A low Kₐ indicates the substance tends to stay intact—less dissociation—while a high Kₐ means it readily separates into its parts. It helps scientists understand the strength and stability of molecular interactions, such as how strongly an acid releases protons or how tightly a drug binds to a receptor, providing insight into the behavior of molecules in biological and chemical systems.