Acid strengths decrease down the tablea.
Conjugate base strengths increase down the tableb.
Name | Acid / Conjugate base | pKa |
---|---|---|
Sulfuric acid | -10 | |
Hydrogen iodide | -10 | |
Hydrogen bromide | -9 | |
Hydrogen chloride | -7 | |
Acetone conjugate acid | -7 | |
Benzenesulfonic acid | -6.5 | |
Acetic acid conjugate acid | -6 | |
Diethyl ether conjugate acid | -3.5 | |
Ethanol conjugate acid | -2 | |
Methanesulfonic acid | -2 | |
Hydronium ion | -1.74 | |
Nitric acid | -1.5 | |
Trifluoroacetic acid | 0.5 | |
Bisulfate ion | 2.0 | |
Benzoic acid | 4.2 | |
Anilinium ion | 4.6 | |
Acetic acid | 4.8 | |
Pyridinium ion | 5.2 | |
Carbonic acid | 6.4 | |
Thiophenol | 6.6 | |
Hydrogen sulfide | 7.0 | |
Peracetic acid | 8.2 | |
Phthalimide | 8.3 | |
Nitroethane | 8.5 | |
Pentane-2,4-dione | 9.0 | |
Ammonium ion | 9.3 | |
Hydrogen cyanide | 9.3 | |
Hexaflurorisopropanol | 9.3 | |
Phenol | 9.9 | |
Bicarbonate ion | 10.3 | |
Methanethiol | 10.3 | |
Ethylammonium ion | 10.8 | |
Diethyl malonate | 12.9 | |
Guanidinium ion | 13.6 | |
Cyclopentadiene | 15.0 | |
Water | 15.74 | |
Ethanol | 16.0 | |
Cyclohexanone | 16.7 | |
Acetamide | 17 | |
Isopropanol | 17.1 | |
t-Butanol | 18.0 | |
Acetone | 19.3 | |
Ethyl acetate | 25 | |
Ethyne | 25 | |
Acetonitrile | 25 | |
Dimethylsulfone | 28 | |
Diemthylsulfoxide | 35 | |
Ammonia | 36 | |
Diisopropylamine | 40 | |
Toluene | 41 | |
Benzene | 43 | |
Propene | 43 | |
Ethene | 44 | |
Methane | approx. 60 |