pH of Organic Acids and Salts
Based on given acidity constants (pKa values) the pH of organic acids for 1, 10, and 100 mmol/L are calculated. The results are listed in the following tables (valid for standard conditions 25, 1 atm):
- organic acids – sorted by formula
- organic acids – sorted by pH
- organic salts – sorted by formula
- inorganic acids and bases
For other reactions we refer to the free software. [ Demo: Online pH-Calculator ]
pH of Organic Acids – Sorted by Formula
| Formula | Name | Alternative name | 1 mM | 10 mM | 100 mM |
|---|---|---|---|---|---|
| CH2O2 | formic acid | methanoic acid | 3.47 | 2.91 | 2.38 |
| C2H2O3 | glyoxilic acid | oxoacetic acid | 3.27 | 2.65 | 2.11 |
| C2H2O4 | oxalic acid | ethanedioic acid | 3.00 | 2.09 | 1.31 |
| C2H4O2 | acetic acid | ethanoic acid | 3.91 | 3.39 | 2.88 |
| C2H4O3 | glocolic acid | hydroxyacetic acid | 3.50 | 2.94 | 2.42 |
| C3H4O2 | acrylic acid | propenoic acid | 3.68 | 3.14 | 2.63 |
| C3H4O3 | pyruvic acid | acetylformic acid | 3.11 | 2.38 | 1.79 |
| C3H4O4 | malonic acid | propanedioic acid | 3.17 | 2.50 | 1.94 |
| C3H6O2 | propanoic acid | propionic acid | 3.96 | 3.44 | 2.94 |
| C3H6O3 | 3-hydroxypropanoic | hydracrylic acid | 3.79 | 3.27 | 2.76 |
| C3H6O3 | lactic acid | milk acid | 3.51 | 2.96 | 2.44 |
| C3H6O4 | glyceric acid | 3.38 | 2.80 | 2.27 | |
| C4H4O4 | fumaric acid | allomaleic acid | 3.19 | 2.57 | 2.03 |
| C4H4O4 | maleic acid | toxilic acid | 3.05 | 2.21 | 1.54 |
| C4H4O5 | oxaloacetic acid | oxalacetic acid | 3.05 | 2.29 | 1.68 |
| C4H6O2 | crotonoic acid | 3-butenoic acid | 3.84 | 3.32 | 2.81 |
| C4H6O3 | acetoacetic acid | diacetic acid | 3.40 | 2.83 | 2.30 |
| C4H6O3 | 2-oxobutanoic acid | alpha-ketobutyric acid | 3.11 | 2.38 | 1.79 |
| C4H6O4 | methylmalonic acid | 3.23 | 2.60 | 2.05 | |
| C4H6O4 | succinic acid | butanedioic acid | 3.65 | 3.12 | 2.61 |
| C4H6O5 | malic acid | 3.33 | 2.74 | 2.21 | |
| C4H6O6 | L-tartaric acid | racemic acid | 3.18 | 2.55 | 2.01 |
| C4H6O6 | DL-tartaric acid | racemic acid | 3.19 | 2.58 | 2.03 |
| C4H6O6 | meso-tartaric acid | racemic acid | 3.24 | 2.62 | 2.08 |
| C4H6O8 | dihydroxytartaric acid | 3.04 | 2.20 | 1.54 | |
| C4H8O2 | butanoic acid | butyric acid | 3.94 | 3.42 | 2.92 |
| C4H8O2 | isobutanoic acid | isobutyric acid | 3.96 | 3.44 | 2.93 |
| C4H8O3 | hydroxybutanoic acid | 3.43 | 2.86 | 2.33 | |
| C5H6O4 | itaconic acid | methylenesuccinic acid | 3.50 | 2.95 | 2.43 |
| C5H6O4 | mesaconic acid | dimethylfumaric acid | 3.23 | 2.61 | 2.06 |
| C5H6O5 | oxoglutaric acid | ketoglutaric acid | 3.09 | 2.36 | 1.77 |
| C5H8O4 | glutaric acid | pentanedioic acid | 3.70 | 3.17 | 2.66 |
| C5H8O4 | methylsuccinic acid | 3.62 | 3.08 | 2.57 | |
| C5H10O2 | valeric acid | pentanoic acid | 3.95 | 3.43 | 2.92 |
| C5H10O2 | isovaleric acid | isopentanoic acid | 3.92 | 3.40 | 2.89 |
| C5H10O2 | pivalic acid | dimethylpropanoic acid | 4.04 | 3.52 | 3.02 |
| C6H6O | phenol | carbolic acid | 6.47 | 5.99 | 5.49 |
| C6H6O6 | cis-aconitic acid | 3.05 | 2.21 | 1.55 | |
| C6H6O6 | trans-aconitic acid | 3.14 | 2.48 | 1.92 | |
| C6H8O6 | ascorbic acid | vitamin C | 3.59 | 3.04 | 2.53 |
| C6H8O7 | citric acid | 3.24 | 2.62 | 2.08 | |
| C6H8O7 | isocitric acid | 3.28 | 2.69 | 2.16 | |
| C6H10O4 | adipic acid | hexanediodic acid | 3.74 | 3.22 | 2.71 |
| C6H12O2 | caproic acid | hexanoic acid | 3.95 | 3.43 | 2.93 |
| C7H6O2 | benzoic acid | 3.66 | 3.12 | 2.60 | |
| C7H6O3 | salicylic acid | 2-hydroxybenzoic acid | 3.21 | 2.57 | 2.02 |
| C7H6O4 | gentisic acid | 2,5-dihydroxybenzoic acid | 3.21 | 2.56 | 2.01 |
| C7H6O4 | protocatechuic acid | 3,4-dihydroxybenzoic acid | 3.78 | 3.25 | 2.74 |
| C7H6O5 | gallic acid | 3,4,5-trihydroxybenz. acid | 3.75 | 3.22 | 2.71 |
| C7H12O2 | cyclohexanecarboxylic | 3.97 | 3.46 | 2.95 | |
| C7H12O4 | pimelic acid | heptanedioic acid | 3.77 | 3.25 | 2.74 |
| C8H6O4 | phthalic acid | ortho-phthalic acid | 3.20 | 2.55 | 2.00 |
| C8H6O4 | isophthalic acid | meta-phthalic acid | 3.33 | 2.76 | 2.24 |
| C8H6O4 | terephthalic acid | para-phthalic acid | 3.36 | 2.79 | 2.26 |
| C8H8O2 | phenylacetic acid | benzeneacetic acid | 3.70 | 3.17 | 2.66 |
| C8H8O2 | toluic acid | ortho-toluic acid | 3.53 | 2.98 | 2.46 |
| C8H8O2 | m-toluic acid | meta-toluic acid | 3.69 | 3.15 | 2.64 |
| C8H8O2 | p-toluic acid | para-toluic acid | 3.73 | 3.20 | 2.69 |
| C8H8O3 | mandelic acid | phenylglycolic acid | 3.34 | 2.75 | 2.22 |
| C8H8O4 | homogentistic acid | 3.74 | 3.21 | 2.70 | |
| C8H14O4 | suberic acid | octanedioic acid | 3.79 | 3.27 | 2.76 |
| C8H16O2 | octanoic acid | caprylic acid | 3.97 | 3.45 | 2.95 |
| C9H8O2 | cinnamic acid | trans-cinnamic acid | 3.76 | 3.23 | 2.72 |
| C9H18O2 | nonanoic acid | pelargonic acid | 4.00 | 3.49 | 2.98 |
pH of Organic Acids – Sorted by increasing pH
| Formula | Name | Alternative name | 1 mM | 10 mM | 100 mM |
|---|---|---|---|---|---|
| C2H2O4 | oxalic acid | ethanedioic acid | 3.00 | 2.09 | 1.31 |
| C4H4O4 | maleic acid | toxilic acid | 3.05 | 2.21 | 1.54 |
| C4H6O8 | dihydroxytartaric acid | 3.04 | 2.20 | 1.54 | |
| C6H6O6 | cis-aconitic acid | 3.05 | 2.21 | 1.55 | |
| C4H4O5 | oxaloacetic acid | oxalacetic acid | 3.05 | 2.29 | 1.68 |
| C5H6O5 | oxoglutaric acid | ketoglutaric acid | 3.09 | 2.36 | 1.77 |
| C3H4O3 | pyruvic acid | acetylformic acid | 3.11 | 2.38 | 1.79 |
| C4H6O3 | 2-oxobutanoic acid | alpha-ketobutyric acid | 3.11 | 2.38 | 1.79 |
| C6H6O6 | trans-aconitic acid | 3.14 | 2.48 | 1.92 | |
| C3H4O4 | malonic acid | propanedioic acid | 3.17 | 2.50 | 1.94 |
| C8H6O4 | phthalic acid | ortho-phthalic acid | 3.20 | 2.55 | 2.00 |
| C4H6O6 | L-tartaric acid | racemic acid | 3.18 | 2.55 | 2.01 |
| C7H6O4 | gentisic acid | 2,5-dihydroxybenzoic acid | 3.21 | 2.56 | 2.01 |
| C7H6O3 | salicylic acid | 2-hydroxybenzoic acid | 3.21 | 2.57 | 2.02 |
| C4H4O4 | fumaric acid | allomaleic acid | 3.19 | 2.57 | 2.03 |
| C4H6O6 | DL-tartaric acid | racemic acid | 3.19 | 2.58 | 2.03 |
| C4H6O4 | methylmalonic acid | 3.23 | 2.60 | 2.05 | |
| C5H6O4 | mesaconic acid | dimethylfumaric acid | 3.23 | 2.61 | 2.06 |
| C4H6O6 | meso-tartaric acid | racemic acid | 3.24 | 2.62 | 2.08 |
| C6H8O7 | citric acid | 3.24 | 2.62 | 2.08 | |
| C2H2O3 | glyoxilic acid | oxoacetic acid | 3.27 | 2.65 | 2.11 |
| C6H8O7 | isocitric acid | 3.28 | 2.69 | 2.16 | |
| C4H6O5 | malic acid | 3.33 | 2.74 | 2.21 | |
| C8H8O3 | mandelic acid | phenylglycolic acid | 3.34 | 2.75 | 2.22 |
| C8H6O4 | isophthalic acid | meta-phthalic acid | 3.33 | 2.76 | 2.24 |
| C8H6O4 | terephthalic acid | para-phthalic acid | 3.36 | 2.79 | 2.26 |
| C3H6O4 | glyceric acid | 3.38 | 2.80 | 2.27 | |
| C4H6O3 | acetoacetic acid | diacetic acid | 3.40 | 2.83 | 2.30 |
| C4H8O3 | hydroxybutanoic acid | 3.43 | 2.86 | 2.33 | |
| CH2O2 | formic acid | methanoic acid | 3.47 | 2.91 | 2.38 |
| C2H4O3 | glocolic acid | hydroxyacetic acid | 3.50 | 2.94 | 2.42 |
| C5H6O4 | itaconic acid | methylenesuccinic acid | 3.50 | 2.95 | 2.43 |
| C3H6O3 | lactic acid | milk acid | 3.51 | 2.96 | 2.44 |
| C8H8O2 | toluic acid | ortho-toluic acid | 3.53 | 2.98 | 2.46 |
| C6H8O6 | ascorbic acid | vitamin C | 3.59 | 3.04 | 2.53 |
| C5H8O4 | methylsuccinic acid | 3.62 | 3.08 | 2.57 | |
| C7H6O2 | benzoic acid | 3.66 | 3.12 | 2.60 | |
| C4H6O4 | succinic acid | butanedioic acid | 3.65 | 3.12 | 2.61 |
| C3H4O2 | acrylic acid | propenoic acid | 3.68 | 3.14 | 2.63 |
| C8H8O2 | m-toluic acid | meta-toluic acid | 3.69 | 3.15 | 2.64 |
| C5H8O4 | glutaric acid | pentanedioic acid | 3.70 | 3.17 | 2.66 |
| C8H8O2 | phenylacetic acid | benzeneacetic acid | 3.70 | 3.17 | 2.66 |
| C8H8O2 | p-toluic acid | para-toluic acid | 3.73 | 3.20 | 2.69 |
| C8H8O4 | homogentistic acid | 3.74 | 3.21 | 2.70 | |
| C6H10O4 | adipic acid | hexanediodic acid | 3.74 | 3.22 | 2.71 |
| C7H6O5 | gallic acid | 3,4,5-trihydroxybenz. acid | 3.75 | 3.22 | 2.71 |
| C9H8O2 | cinnamic acid | trans-cinnamic acid | 3.76 | 3.23 | 2.72 |
| C7H6O4 | protocatechuic acid | 3,4-dihydroxybenzoic acid | 3.78 | 3.25 | 2.74 |
| C7H12O4 | pimelic acid | heptanedioic acid | 3.77 | 3.25 | 2.74 |
| C3H6O3 | 3-hydroxypropanoic | hydracrylic acid | 3.79 | 3.27 | 2.76 |
| C8H14O4 | suberic acid | octanedioic acid | 3.79 | 3.27 | 2.76 |
| C4H6O2 | crotonoic acid | 3-butenoic acid | 3.84 | 3.32 | 2.81 |
| C2H4O2 | acetic acid | ethanoic acid | 3.91 | 3.39 | 2.88 |
| C5H10O2 | isovaleric acid | isopentanoic acid | 3.92 | 3.40 | 2.89 |
| C4H8O2 | butanoic acid | butyric acid | 3.94 | 3.42 | 2.92 |
| C5H10O2 | valeric acid | pentanoic acid | 3.95 | 3.43 | 2.92 |
| C4H8O2 | isobutanoic acid | isobutyric acid | 3.96 | 3.44 | 2.93 |
| C6H12O2 | caproic acid | hexanoic acid | 3.95 | 3.43 | 2.93 |
| C3H6O2 | propanoic acid | propionic acid | 3.96 | 3.44 | 2.94 |
| C7H12O2 | cyclohexanecarboxylic | 3.97 | 3.46 | 2.95 | |
| C8H16O2 | octanoic acid | caprylic acid | 3.97 | 3.45 | 2.95 |
| C9H18O2 | nonanoic acid | pelargonic acid | 4.00 | 3.49 | 2.98 |
| C5H10O2 | pivalic acid | dimethylpropanoic acid | 4.04 | 3.52 | 3.02 |
| C6H6O | phenol | carbolic acid | 6.47 | 5.99 | 5.49 |
pH of Organic Salts – Sorted by Formula
| Formula | Name | 1 mM | 10 mM | 100 mM | 1000 mM |
|---|---|---|---|---|---|
| (NH4)2C6H6O7 | diammonium hydrogen citrate | 5.48 | 5.29 | 5.04 | 6.16 |
| (NH4)3C6H5O7 | triammonium citrate | 7.50 | 7.40 | 7.32 | 8.18 |
| Ca(CH3COO)2 | calcium acetate | 8.00 | 8.43 | 8.77 | 9.13 |
| Ca(HCOO)2 | calcium formate | 7.51 | 7.92 | 8.24 | 8.47 |
| CaHC6H5O7 | calcium hydrogen citrate | 4.81 | 4.44 | 4.12 | 3.85 |
| Ca(C3H5O3)2 | calcium lactate | 7.56 | 7.97 | 8.28 | 8.50 |
| Fe(HCOO)2 | iron(II) formate | 6.82 | 6.89 | 7.03 | 7.21 |
| K2HC6H5O7 | dipotassium hydrogen citrate | 5.48 | 5.27 | 4.87 | 3.67 |
| K3C6H5O7 | tripotassium citrate | 8.59 | 8.90 | 9.01 | 7.47 |
| KCH3COO | potassium acetate | 7.87 | 8.33 | 8.75 | 9.06 |
| KHCOO | potassium formate | 7.40 | 7.83 | 8.25 | 8.58 |
| KH2C6H5O7 | potassium dihydrogen citrate | 4.07 | 3.87 | 3.71 | 3.54 |
| KC3H5O3 | potassium lactate | 7.45 | 7.89 | 8.30 | 8.62 |
| Mg(CH3COO)2 | magnesium acetate | 7.95 | 8.23 | 8.41 | 8.78 |
| Mg(HCOO)2 | magnesium formate | 7.46 | 7.73 | 7.90 | 8.06 |
| MgHC6H5O7 | magnesium hydrogen citrate | 4.79 | 4.40 | 4.08 | 3.79 |
| Mg(C3H5O3)2 | magnesium lactate | 7.52 | 7.78 | 7.94 | 8.09 |
| Na2HC6H5O7 | disodium hydrogen citrate | 5.48 | 5.28 | 4.88 | 3.72 |
| Na3C6H5O7 | trisodium citrate | 8.59 | 8.90 | 9.04 | 9.26 |
| NaCH3COO | sodium acetate | 7.87 | 8.33 | 8.75 | 9.04 |
| NaHCOO | sodium formate | 7.40 | 7.83 | 8.25 | 8.57 |
| NaH2C6H5O7 | sodium dihydrogen citrate | 4.07 | 3.87 | 3.71 | 3.48 |
| NaHC6H6O6 | sodium ascorbate | 7.48 | 7.71 | 7.64 | 7.62 |
| NaC3H5O3 | sodium lactate | 7.48 | 7.85 | 8.30 | 8.61 |
| NH4CH3COO | ammonium acetate | 7.00 | 7.00 | 7.00 | 6.95 |
| NH4HCOO | ammonium formate | 6.53 | 6.50 | 6.49 | 6.45 |
| NH4C6H7O7 | ammonium dihydrogen citrate | 4.07 | 3.87 | 3.72 | 3.71 |
| NH4C6H7O6 | ammonium ascorbate | 6.66 | 6.64 | 6.64 | 6.59 |
| NH4C3H5O3 | ammonium lactate | 6.58 | 6.56 | 6.55 | 6.50 |
[last modified: 2021-01-17]