Dissociation Constants for Common Acids and Bases @ 25oC
| Acid | Formula | pKa1 | pKa2 | pKa3 |
| acetic | HC2H3O2 | 4.76 | ||
| acetylsalicylic | C8H7O2COOH | 3.48 | ||
| acrylic | HC3H3O2 | 4.26 | ||
| arsenic | H3AsO4 | 2.30 | 7.03 | 11.53 |
| arsenious | H3AsO3 | 9.18 | ||
| ascrobic | H2C6H6O6 | 4.10 | 11.80 | |
| benzoic | C6H5COOH | 4.20 | ||
| boric | H3BO3 | 9.23 | ||
| bromoacetic | HC2H2BrO2 | 2.89 | ||
| butyric | HC4H7O2 | 4.82 | ||
| carbonic | H2CO3 | 6.37 | 10.25 | |
| chloroacetic | CH2ClCOOH | 2.85 | ||
| chlorous | HClO2 | 1.92 | ||
| chromium ion | Cr3+(aq) | 4.0 | ||
| cinnamic | HC9H7O2 | 4.44 | ||
| citric | H3C6H5O7 | 3.13 | 4.76 | 6.40 |
| cyanic | HCNO | 3.46 | ||
| cyanuric | HC3H2N3O3 | 6.78 | ||
| dichloroacetic | HC2HCl2O2 | 1.26 | ||
| fluoroacetic | HC2H2FO2 | 2.59 | ||
| formic | HCOOH | 3.75 | ||
| germanic | H2GeO3 | 9.0 | 12.4 | |
| hydrazoic | HN3 | 4.72 | ||
| hydrocyanic | HCN | 9.23 | ||
| hydrofluoric | HF | 3.18 | ||
| hydrogen peroxide | H2O2 | 11.65 | ||
| hydroselenic | H2Se | 3.89 | 11.0 | |
| hydrosulfuric | H2S | 7.06 | 12.92? | |
| hydrotelluric | H2Te | 2.64 | 10.80 | |
| hypobromous | HBrO | 9.24 | ||
| hypochlorous | HClO | 7.55 | ||
| hypoiodous | HIO | 10.64 | ||
| hyponitrous | H2N2O2 | 7.05 | 11.4 | |
| hypophosphorous | H3PO2 | 1.23 | ||
| iodic | HIO3 | 0.80 | ||
| iodoacetic | HC2H2IO2 | 3.18 | ||
| lactic | HC3H5O3 | 3.08 | ||
| maleic | HOOCCH:CHCOOH | 1.84 | 6.07 | |
| malonic | H2C3H2O4 | 2.82 | 5.70 | |
| nitrous | HNO2 | 3.14 | ||
| oxalic | H2C2O4 | 1.23 | 4.19 | |
| phenol | HOC6H5 | 10.00 | ||
| phosphoric | H3PO4 | 2.12 | 7.21 | 12.67 |
| phosphorous | H3PO3 | 1.80 | 6.15 | |
| phthalic | H2C8H4O4 | 2.92 | 5.41 | |
| proprionic | HC3H5O2 | 4.89 | ||
| salicylic | HC7H5O3 | 1.96 | ||
| selenic | H2SeO4-3 | 1.66 | ||
| selenous | H2SeO3 | 2.64 | 8.27 | |
| succinic | H2C4H4O4 | 4.21 | 5.64 | |
| sulfuric | H2SO4 | none | 1.92 | |
| sulfurous | H2SO3 | 1.89 | 7.21 | |
| thiophenol | HSC6H5 | 6.49 | ||
| trichloroacetic | HC2Cl3O2 | 0.70 | ||
| Base | Formula | pKb1 | pKb2 | |
| ammonia | NH3 | 4.76 | ||
| aniline | C6H5NH2 | 9.37 | ||
| codeine | C18H21O3N | 6.05 | ||
| diethylamine | (C2H5)2NH | 4.51 | ||
| dimethylamine | (CH3)2NH | 3.23 | ||
| ethylamine | C2H5NH2 | 3.36 | ||
| hydrazine | N2H4 | 5.77 | 15.05 | |
| hydroxylamine | HONH2 | 9.04 | ||
| methylamine | CH3NH2 | 3.38 | ||
| morphine | C17H19O3N | 6.13 | ||
| piperidine | C5H11N | 2.88 | ||
| pyridine | C5H5N | 8.70 | ||
| quinoline | C9H7N | 9.20 | ||
| triethanolamine | C6H15O3N | 6.24 | ||
| triethylamine | (C2H5)3N | 3.28 | ||
| trimethylamine | (CH3)3N | 4.20 |