The word hydrolysis is applied to chemical reactions in which a substance reacts with water. In organic chemistry, the products of the reaction are usually molecular, being formed by combination with H and OH groups (e.g., hydrolysis of an ester to an alcohol and a carboxylic acid). In inorganic chemistry, the word most often applies to cations forming soluble hydroxide or oxide complexes with, in some cases, the formation of hydroxide and oxide precipitates.

Metal hydrolysis and associated equilibrium constant values

The hydrolysis reaction for a hydrated metal ion in aqueous solution can be written as: and the corresponding formation constant as: and associated equilibria can be written as:

Aluminium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Americium(III)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Americium(V)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Antimony(III)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Antimony(V)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Arsenic(III)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Arsenic(V)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Barium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Berkelium(III)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Beryllium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Bismuth

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Boron

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Cadmium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Calcium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Californium(III)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Cerium(III)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Chromium(II)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K (The divalent state is unstable in water, producing hydrogen whilst being oxidised to a higher valency state (Baes and Mesmer, 1976). The reliability of the data is in doubt.):

Chromium(III)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Chromium(VI)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Cobalt(II)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Cobalt(III)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Copper(I)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Copper(II)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Curium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Dysprosium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Erbium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Europium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Gadolinium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Gallium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Germanium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Gold(III)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Hafnium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

• Errors in compilations concerning equilibrium and/or data elaboration. Data not recommended. Strongly suggested to refer to the original papers.

Holmium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Indium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Iridium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Iron(II)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Iron(III)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Lanthanum

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Lead(II)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Lead(IV)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Lithium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Magnesium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Manganese(II)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Manganese(III)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Mercury(I)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K: (a) 0.5 M HClO4

Mercury(II)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Molybdenum(VI)

Hydrolysis constants (log values) in critical compilations at infinite dilution, T = 298.15 K and I = 3 M NaClO4 (a) or 0.1 M Na+ medium, Data at I = 0 are not available (b):

Neodymium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Neptunium(III)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Neptunium(IV)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Neptunium(V)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Neptunium(VI)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Nickel(II)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Niobium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Osmium(VI)

Hydrolysis constants (log values) in critical compilations at infinite dilution, I = 0.1 M and T = 298.15 K:

Osmium(VIII)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K: (a) At I = 0.1 M (b) At I = 2.5 M

Palladium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Plutonium(III)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Plutonium(IV)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Plutonium(V)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Plutonium(VI)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Potassium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Praseodymium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Radium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Rhodium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Samarium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Scandium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Selenium(–II)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Selenium(IV)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Selenium(VI)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Silicon

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Silver

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Sodium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Strontium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Tantalum

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K: (a) The number of significant figures are retained to minimise propagation of round-off errors; they should not be taken to indicate the relative uncertainty of the values, which is always at least one order of magnitude less than indicated.

Tellurium(-II)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K: (a) The number of significant figures are retained to minimise propagation of round-off errors; they should not be taken to indicate the relative uncertainty of the values, which is always at least one order of magnitude less than indicated.

Tellurium(IV)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K: (a) The number of significant figures are retained to minimise propagation of round-off errors; they should not be taken to indicate the relative uncertainty of the values, which is always at least one order of magnitude less than indicated.

Tellurium(VI)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K: (a) The number of significant figures are retained to minimise propagation of round-off errors; they should not be taken to indicate the relative uncertainty of the values, which is always at least one order of magnitude less than indicated.

Terbium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Thallium(I)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K: (a) The number of significant figures are retained to minimise propagation of round-off errors; they should not be taken to indicate the relative uncertainty of the values, which is always at least one order of magnitude less than indicated.

Thallium(III)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K: (a) The number of significant figures are retained to minimise propagation of round-off errors; they should not be taken to indicate the relative uncertainty of the values, which is always at least one order of magnitude less than indicated.

Thorium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Thulium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Tin(II)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Tin(IV)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Tungsten

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Titanium(III)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Titanium(IV)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Uranium(IV)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Uranium(VI)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Vanadium(IV)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Vanadium(V)

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Ytterbium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Yttrium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Zinc

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K:

Zirconium

Hydrolysis constants (log values) in critical compilations at infinite dilution and T = 298.15 K: * Errors in compilations concerning equilibrium and/or data elaboration. Data not recommended. It is strongly suggested to refer to the original papers.