acid dissociation constant (Ka)

The acid dissociation constant (Ka) measures how well an acid donates protons (H⁺ ions) to water in a solution. A higher Ka value indicates a stronger acid that dissociates more completely, producing more hydrogen ions. For example, hydrochloric acid (HCl) has a high Ka and readily dissociates, making it strong. Conversely, acetic acid (found in vinegar) has a lower Ka, indicating it does not dissociate as completely and is therefore a weaker acid. This constant helps in understanding an acid's strength and behavior in chemical reactions.