Ka2 refers to the acidity constant associated with the second ionization of citric acid. It measures how easily the second hydrogen ion (H+) can be removed after one has already been removed during ionization.
Related terms
Ionization: The process by which an atom or molecule gains or loses electrons, forming ions.
Acidity Constant: A numerical value indicating the degree of acidity or basicity of an aqueous solution.
Hydrogen Ion (H+): A positively charged ion consisting solely of a proton, often involved in acidic reactions.