pKa是化合物非常重要的物性参数，其值会影响物质的特征，例如活跃性、水溶性及光谱性质。在生物化学上，蛋白质及氨基酸侧链的pKa值是对酶的活跃性及蛋白质的稳定性十分重要。本文推荐一个可以免费查询化合物pKa的网站，https://www.chem.wisc.edu/areas/reich/pkatable/index.htm
这个网站几乎覆盖所有化合物种类，上千种化合物的pKa
-Acetylenes
-Acids (Inorganic)
-Adenine (N-H)
-Alcohols (O-H)
-Allyl
-Amides (C-H, N-H)
-Amidines (N-H)
-Amines (C-H, N-H)
-Ammonium (C-H, N-H)
-Aniline (N-H)
-Arsonium
-Azoles (N-H)
-Benzyl
-Carbamates (N-H)
-Carbazoles (N-H)
-Carbenes, Amino
-Carboxylic Acids (O-H)
-Cyclopentadiene
-Dithianes
-Esters
-Ethers
-Fluorenes
-Germanes (Ge-H)
-Guanidine (N-H)
-Halides
-Heteroaromatics
-Horner-Wadsworth Emmons Reag
-Hydantoin
-Hydrazine, Hydrazone
-Hydrazoic Acid
-Hydrogen cyanide
-Hydrohalic acids
-Hydrocarbons
-Hydroxylamines, Hydroxamic Acids
-Imidazoles (N-H)
-Imidazolium
-Imine
-Imides
-Indene
-Indole (N-H)
-Isocyanide
-Inorganic Acids
-Ketones
-Ketones, beta-di
-Lactams (C-H, N-H)
-Lactones
-Malonic Esters
-Malononitriles
-Mercaptans (S-H)
-Methane
-Nitriles
-Nitroalkanes
-Oxazoles
-Oxazolinone
-Oximes
-Phenols (O-H)
-Phosphines, Phosphonates
-Phosphonium
-Piperidones
-Propargyl
-Pyridones
-Pyridyl
-Pyridinium
-Pyrroles (N-H)
-Pyrrolidinone
-Selenols (Se-H)
-Silanes (C-H)
-Sulfides
-Seleides
-Sulfimides (Sulfilimines)
-Sulfinic, Sulfonic Acids (O-H)
-Sulfonamides
-Sulfonates (C-H)
-Sulfones
-Sulfonium
-Sulfoxides
-Sulfoximides
-Tetraazoles (N-H)
-Triazoles (N-H)
-Thiazole, Thiazolium
-Thioamides (N-H)
-Thioestr
-Thiolactones
-Thiols (S-H)
-Urazole
-Urethane (N-H)
-Uracil (N-H)
-Ureas (N-H)
-Water
-Wittig Reagents