Compound

T°C

Step

K

pK

Acetic

25

1.76 x 10^–5

4.75

Acetoacetic

18

2.62 x 10^–4

3.58

Acrylic

25

5.6 x 10^–5

4.25

Adipamic

25

2.35 x 10^–5

4.63

Adipic

25

1

3.71 x 10^–5

4.43

Adipic

25

2

3.87 x 10^–5

4.41

d-Alanine

25

1.35 x 10^–10

9.87

Allantoin

25

1.10 x 10^–9

8.96

Alloxanic

25

2.3 x 10^–7

6.64

a-Aminoacetic (glycine)

25

1.67 x 10^–10

9.78

2-Aminobenzoic

25

1.07 x 10^–7

6.97

3-Aminobenzoic

25

1.67 x 10^–5

4.78

4-Aminobenzoic

25

1.2 x 10^–5

4.92

2-Aminobenzosulfonic

25

3.3 x 10^–3

2.48

3-Aminobenzosulfonic

25

1.85 x 10^–4

3.73

4-Aminobenzosulfonic

25

5.81 x 10^–4

3.24

Anisic

25

3.38 x 10^–5

4.47

o-b-Anisylpropanoic

25

1.59 x 10^–5

4.80

m-b-Anisylpropanoic

25

2.24 x 10^–5

4.65

p-b-Anisylpropanoic

25

2.04 x 10^–5

4.69

Ascorbic

24

1

7.94 x 10^–5

4.10

Ascorbic

16

2

1.62 x 10^–12

11.79

DL-Aspartic

25

1

1.38 x 10^–4

3.86

DL-Aspartic

25

2

1.51 x 10^–10

9.82

Barbituric

25

9.8 x 10^–5

4.01

Benzoic

25

6.46 x 10^–5

4.19

Benzoic, 2-amino

25

1.07 x 10^–7

6.97

Benzoic, 3-amino

25

1.67 x 10^–5

4.78

Benzoic, 4-amino

25

1.2 x 10^–5

4.92

Benzoic, 2-chloro

25

1.20 x 10^–3

2.92

Benzoic, 3-chloro

25

1.51 x 10^–4

3.82

Benzoic, 4-chloro

25

1.04 x 10^–4

3.98

Benzoic, ethyl

25

4.47 x 10^–5

4.35

Benzoic, fluoro

17

1.25 x 10^–3

2.90

Benzoic, 2,2-dihydroxy

25

1.14 x 10^–3

2.94

Benzoic, 2,5-dihydroxy

25

1.08 x 10^–3

2.97

Benzoic, 3,4-dihydroxy

25

3.3 x 10^–5

4.48

Benzoic, 3,5-dihydroxy

25

9.1 x 10^–5

4.04

Benzoic, 2-hydroxy

19

1

1.07 x 10^–3

2.97

Benzoic, 2-hydroxy

18

2

4 x 10^–14

13.40

Benzoic, 3-hydroxy

19

1

8.7 x 10^–5

4.06

Benzoic, 3-hydroxy

19

2

1.2 x 10^–10

9.92

Benzoic, 4-hydroxy

19

1

3.3 x 10^–5

4.48

Benzoic, 4-hydroxy

19

2

4.8 x 10^–10

9.32

Benzoic, 2-iodo

25

1.4 x 10^–3

2.85

Benzoic, 3-iodo

25

1.6 x 10^–4

3.80

Benzoic, methyl-o-amino

25

4.6 x 10^–6

5.34

Benzoic, methyl-m-amino

25

8 x 10^–6

5.10

Benzoic, methyl-p-amino

25

9.2 x 10^–6

5.04

Benzoic, 2-nitro

18

6.95 x 10^–3

2.16

Benzoic, 3-nitro

25

3.4 x 10^–4

3.47

Benzoic, 4-nitro

25

3.93 x 10^–4

3.41

Benzoic, 2-Phenyl

25

3.47 x 10^–4

3.46

Benzoic, iso-propyl

25

3.98 x 10^–5

4.40

Benzoic, 2,4,6-trihydroxy

25

2.1 x 10^–2

1.68

Benzosulfonic

25

2 x 10^–1

0.70

Bromoacetic

25

2.05 x 10^–3

2.69

Bromoethanoic

25

2.05 x 10^–3

2.69

Benzoic, 2-bromo

25

1.45 x 10^–3

2.84

3-Bromobenzoic

25

1.37 x 10^–4

3.86

n-Butanoic

20

1.54 x 10^–5

4.81

butanoic

20

1.54 x 10^–5

4.81

iso-Butanoic

18

1.44 x 10^–5

4.84

Butanoic, 3-hydroxy

25

2 x 10^–5

4.70

Butanoic, 4-hydroxy

25

1.9 x 10^–5

4.72

Butanoic, 3-methyl

25

1.7 x 10^–5

4.77

Butanoic, 4-phenyl

25

1.74 x 10^–5

4.76

Butanoic, 2-chloro

RT

1.39 x 10^–3

2.86

Butanoic, 3-chloro

RT

8.9 x 10^–5

4.05

Butanoic, 4-chloro

RT

3.0 x 10^–5

4.52

3-Butenoic

25

4.57 x 10^–5

4.34

Cacodylic

25

6.4 x 10^–7

6.19

n-Caproic

18

1.43 x 10^–5

4.83

iso-Caproic

18

1.46 x 10^–5

4.84

Chloroacetic

25

1.40 x 10^–3

2.85

Chloroethanoic

25

1.40 x 10^–3

2.85

2-Chlorobenzoic

25

1.20 x 10^–3

2.92

3-Chlorobenzoic

25

1.51 x 10^–4

3.82

4-Chlorobenzoic

25

1.04 x 10^–4

3.98

2-Chlorobutanoic

RT

1.39 x 10^–3

2.86

3-Chlorobutanoic

RT

8.9 x 10^–5

4.05

4-Chlorobutanoic

RT

3.0 x 10^–5

4.52

o-Chlorocinnamic

25

5.89 x 10^–5

4.23

m-Chlorocinnamic

25

5.13 x 10^–5

4.29

p-Chlorocinnamic

25

3.89 x 10^–5

4.41

2-Chlorophenol

25

3.2 x 10^–9

8.49

3-Clorophenol

25

1.4 x 10^–9

8.85

4-Chlorophenol

25

6.6 x 10^–10

9.18

2-Chlorophenoxyacetic

25

8.91 x 10^–4

3.05

3-Chlorophenoxyacetic

25

8.51 x 10^–4

3.07

4-Chlorophenoxyacetic

25

7.94 x 10^–4

3.10

2-Chlorophenylacetic

25

1.18 x 10^–5

4.07

3-Chlorophenylacetic

25

7.25 x 10^–5

4.14

4-Chlorophenylacetic

25

6.46 x 10^–5

4.19

2-(2-chlorophenyl)propanoic

25

2.63 x 10^–4

4.58

2-(3-chlorophenyl)propanoic

25

2.57 x 10^–5

4.59

2- (4-chlorophenyl)propanoic

25

2.46 x 10^–5

4.61

2-Chloropropanoic

25

1.47 x 10^–3

2.83

3-Chloropropanoic

25

1.04 x 10^–4

3.98

cis-Cinnamic (3-phenyl-2-propenoic)

25

1.3 x 10^–4

3.89

trans-Cinnamic (3-phenyl-2-propenoic)

25

3.65 x 10^–5

4.44

Citric (2-hydroxy-1,2,3-propanetricarboxylic)

18

1

7.10 x 10^–4

3.14

Citric (2-hydroxy-1,2,3-propanetricarboxylic)

18

2

1.68 x 10^–5

4.95

Citric (2-hydroxy-1,2,3-propanetricarboxylic)

18

3

6.4 x 10^–6

5.39

o-Cresol

25

6.3 x 10^–11

10.20

m-Cresol

25

9.8 x 10^–11

10.01

p-Cresol

25

6.7 x 10^–11

10.17

Crotonic (trans-)

25

2.03 x 10^–5

4.69

Cyanoacetic

25

3.65 x 10^–3

2.45

4-Cyanobutanoic

25

3.80 x 10^–3

2.42

2-Cyanophenoxyacetic

25

1.05 x 10^–3

2.98

3-Cyanophenoxyacetic

25

9.33 x 10^–4

3.03

4-Cyanophenoxyacetic

25

1.18 x 10^–3

2.93

Cyanopropanoic

25

3.6 x 10^–3

2.44

Cyclohexane-1 : 1-dicarboxylic

25

1

3.55 x 10^–4

3.45

Cyclohexane-1 : 1-dicarboxylic

25

2

7.76 x 10^–7

6.11

Cyclopropane-1 : 1-dicarboxylic

25

1

1.51 x 10^–2

1.82

Cyclopropane-1 : 1-dicarboxylic

25

2

3.72 x 10^–8

7.43

DL-Cysteine

30

1

7.25 x 10^–9

8.14

DL-Cysteine

30

2

4.6 x 10^–11

10.34

L-Cystine

25

1

1.4 x 10^–8

7.85

L-Cystine

25

2

1.4 x 10^–10

9.85

Deuteroacetic (in D₂O)

25

5.5 x 10^–6

5.25

Dichloroacetic

25

3.32 x 10^–2

1.48

Dichloroethanoic

25

3.32 x 10^–2

1.48

Dichloroacetylacetic

-

7.8 x 10^–3

2.11

2,3-Dichlorophenol

25

3.6 x 10^–8

7.44

2,2-Dihydroxybenzoic

25

1.14 x 10^–3

2.94

2,5-Dihydroxybenzoic

25

1.08 x 10^–3

2.97

3,4-Dihydroxybenzoic

25

3.3 x 10^–5

4.48

3,5-Dihydroxybenzoic

25

9.1 x 10^–5

4.04

Dihydroxymalic

25

1.2 x 10^–2

1.92

Dihydroxytartaric

25

1.2 x 10^–2

1.92

Dimethylglycine

25

1.3 x 10^–10

9.89

Dimethylmalic

25

1

6.83 x 10^–4

3.17

Dimethylmalic

25

2

8.72 x 10^–7

6.06

Dimethylmalonic

25

7.08 x 10^–4

3.15

Dimethylpropanoic

18

9.4 x 10^–6

5.03

Dinitrophenol (2,4-)

15

1.1 x 10^–4

3.96

Dinicotinic

25

1.6 x 10^–3

2.80

Dinitrophenol (3,6-)

15

7.1 x 10^–6

5.15

Diphenylacetic

25

1.15 x 10^–4

3.94

Diphenylethanoic

25

1.15 x 10^–4

3.94

Ethanoic

25

1.76 x 10^–5

4.75

Ethanoic, bromo

25

2.05 x 10^–3

2.69

Ethanoic, chloro

25

1.40 x 10^–3

2.85

Ethanoic, dichloro

25

3.32 x 10^–2

1.48

Ethanoic, 2-chlorophenoxy

25

8.91 x 10^–4

3.05

Ethanoic, 3-chlorophenoxy

25

8.51 x 10^–4

3.07

Ethanoic, 4-chlorophenoxy

25

7.94 x 10^–4

3.10

Ethanoic, 2-chlorophenyl

25

1.18 x 10^–5

4.07

Ethanoic, 3-chlorophenyl

25

7.25 x 10^–5

4.14

Ethanoic, 4-chlorophenyl

25

6.46 x 10^–5

4.19

Ethanoic, iodo

25

7.5 x 10^–4

3.12

Ethanoic, 2-nitrophenyl

25

1.00 x 10^–5

4.00

Ethanoic, 3-nitrophenyl

25

1.07 x 10^–4

3.97

Ethanoic, 4-nitrophenyl

25

1.41 x 10^–4

3.85

Ethanoic, phenyl

18

5.2 x 10^–5

4.28

Ethanoic, diphenyl

25

1.15 x 10^–4

3.94

Ethanoic, phenylethyl

25

4.27 x 10^–5

4.37

Ethanoic, thio

25

4.7 x 10^–4

3.33

Ethanoic, trichloro

25

2 x 10^–1

0.70

Ethylbenzoic

25

4.47 x 10^–5

4.35

Ethylphenylacetic

25

4.27 x 10^–5

4.37

Fluorobenzoic

17

1.25 x 10^–3

2.90

Formic

20

1.77 x 10^–4

3.75

trans -Fumaric (1,2-ethenedicarboxylic)

18

1

9.30 x 10^–4

3.03

trans -Fumaric (1,2-ethenedicarboxylic)

18

2

3.62 x 10^–5

4.44

Furancarboxylic

25

7.1 x 10^–4

3.15

Furoic

25

6.76 x 10^–4

3.17

Gallic

25

3.9 x 10^–5

4.41

Glutaramic

25

3.98 x 10^–5

4.60

Glutaric

25

1

4.58 x 10^–5

4.34

Glutaric

25

2

3.89 x 10^–6

5.41

Glycerol

25

7 x 10^–15

14.15

Glycine

25

1.67 x 10^–10

9.87

Glycol

25

6 x 10^–15

14.22

Glycolic

25

1.48 x 10^–4

3.83

Heptanoic

25

1.28 x 10^–5

4.89

Hexahydrobenzoic (cyclohexylmethanoic)

25

1.26 x 10^–5

4.90

Hexanoic

25

1.31 x 10^–5

4.88

Hexanoic

18

1.43 x 10^–5

4.83

Hippuric

25

1.57 x 10^–4

3.80

Histidine

25

6.7 x 10^–10

9.17

Hydroquinone

20

4.5 x 10^–11

10.35

2-Hydroxybenzoic

19

1

1.07 x 10^–3

2.97

2-Hydroxybenzoic

18

2

4 x 10^–14

13.40

3-Hydroxybenzoic

19

1

8.7 x 10^–5

4.06

3-Hydroxybenzoic

19

2

1.2 x 10^–10

9.92

4-Hydroxybenzoic

19

1

3.3 x 10^–5

4.48

4-Hydroxybenzoic

19

2

4.8 x 10^–10

9.32

3-Hydroxybutanoic

25

2 x 10^–5

4.70

4-Hydroxybutanoic

25

1.9 x 10^–5

4.72

3-Hydroxypropanoic

25

3.1 x 10^–5

4.51

g-Hydroxyquinoline

20

3.1 x 10^–10

9.51

Iodoethanoic

25

7.5 x 10^–4

3.12

2-Iodobenzoic

25

1.4 x 10^–3

2.85

3-Iodobenzoic

25

1.6 x 10^–4

3.80

Itaconic

25

1

1.40 x 10^–4

3.85

Itaconic

25

2

3.56 x 10^–6

5.45

Lactic

100

8.4 x 10^–4

3.08

Lutidinic

25

7.0 x 10^–3

2.15

Lysine

25

2.95 x 10^–11

10.53

Maleic (cis-butenedioic)

25

1

1.42 x 10^–2

1.83

Maleic (cis-butenedioic)

25

2

8.57 x 10^–7

6.07

Malic (hydroxybutanedioic)

25

1

3.9 x 10^–4

3.40

Malic (hydroxybutanedioic)

25

2

7.8 x 10^–6

5.11

Malonic (propanedioic)

25

1

1.49 x 10^–3

2.83

Malonic (propanedioic)

25

2

2.03 x 10^–6

5.69

DL-Mandelic

25

1.4 x 10^–4

3.85

Mesaconic

25

1

8.22 x 10^–4

3.09

Mesaconic

25

2

1.78 x 10^–5

4.75

Mesitylenic

25

4.8 x 10^–5

4.32

Methanoic

20

1.77 x 10^–4

3.75

Methanoic, cyclohexyl

25

1.26 x 10^–5

4.90

Methyl-o-aminobenzoic

25

4.6 x 10^–6

5.34

Methyl-m-aminobenzoic

25

8 x 10^–6

5.10

Methyl-p-aminobenzoic

25

9.2 x 10^–6

5.04

3-Methylbutanoic

25

1.7 x 10^–5

4.77

o-Methylcinnamic

25

3.16 x 10^–5

4.50

m-Methylcinnamic

25

3.63 x 10^–5

4.44

p-Methylcinnamic

25

2.76 x 10^–5

4.56

b-Methylglutaric

25

5.75 x 10^–5

4.24

n-Methylglycine

18

1.2 x 10^–10

9.92

Methylmalonic

25

1.17 x 10^–4

3.07

4-Methylpentanoic

18

1.46 x 10^–5

4.84

2-Methylpropanoic

18

1.44 x 10^–5

4.84

Methylsuccinic

25

1

7.4 x 10^–5

4.13

Methylsuccinic

25

2

2.3 x 10^–6

5.64

Naphthalenesulfonic

25

2.7 x 10^–1

0.57

a-Naphthoic

25

2 x 10^–4

3.70

b-Naphthoic

25

6.8 x 10^–5

4.17

a-Naphthol

25

4.6 x 10^–10

9.34

b-Naphthol

25

3.1 x 10^–10

9.51

Nitrobenzene

0

1.05 x 10^–4

3.98

2-Nitrobenzoic

18

6.95 x 10^–3

2.16

3-Nitrobenzoic

25

3.4 x 10^–4

3.47

4-Nitrobenzoic

25

3.93 x 10^–4

3.41

2-Nitrophenol

25

6.8 x 10^–8

7.17

3-Nitrophenol

25

5.3 x 10^–9

8.28

4-Nitrophenol

25

7 x 10^–8

7.15

2-Nitrophenylethanoic

25

*1.00 x 10^–5

*4.00

3-Nitrophenylethanoic

25

1.07 x 10^–4

3.97

4-Nitrophenylethanoic

25

1.41 x 10^–4

3.85

o-b-Nitrophenylpropanoic

25

3.16 x 10^–5

4.50

p-b-Nitrophenylpropanoic

25

3.39 x 10^–5

4.47

Nonanic

25

1.09 x 10^–5

4.96

Octanoic

25

1.28 x 10^–5

4.89

Oxalic (ethanedioic)

25

1

5.90 x 10^–2

1.23

Oxalic (ethanedioic)

25

2

6.40 x 10^–5

4.19

Pentanoic

18

1.51 x 10^–5

4.82

Pentanoic, 4-methyl

18

1.46 x 10^–5

4.84

Phenol

20

1.28 x 10^–10

9.89

Phenol, 2-chloro

25

3.2 x 10^–9

8.49

Phenol, 3-chloro

25

1.4 x 10^–9

8.85

Phenol, 4-chloro

25

6.6 x 10^–10

9.18

Phenol, 2,3-dichloro

25

3.6 x 10^–8

7.44

Phenol, trichloro

25

1 x 10^–6

6.00

Phenol, 2-nitro

25

6.8 x 10^–8

7.17

Phenol, 3-nitro

25

5.3 x 10^–9

8.28

Phenol, 4-nitro

25

7 x 10^–8

7.15

Phenol, 2,4-dinitro

15

1.1 x 10^–4

3.96

Phenol, 3,6-dinitro

15

7.1 x 10^–6

5.15

Phenol, 2,4,6-trinitro

25

4.2 x 10^–1

0.38

Phenylacetic

18

5.2 x 10^–5

4.28

2-Phenylbenzoic

25

3.47 x 10^–4

3.46

4-Phenylbutanoic

25

1.74 x 10^–5

4.76

2-Phenylpropanoic

25

2.27 x 10^–5

4.64

3-Phenylpropanoic

25

4.25 x 10^–5

4.37

o-Phthalic

25

1

1.3 x 10^–3

2.89

o-Phthalic

25

2

3.9 x 10^–6

5.51

m-Phthalic

25

1

2.9 x 10^–4

3.54

m-Phthalic

18

2

2.5 x 10^–5

4.60

p-Phthalic

25

1

3.1 x 10^–4

3.51

p-Phthalic

16

2

1.5 x 10^–5

4.82

Picric

25

4.2 x 10^–1

0.38

Pimelic

25

3.09 x 10^–5

4.71

Propanoic

25

1.34 x 10^–5

4.87

Propanoic, 2-chloro

25

1.47 x 10^–3

2.83

Propanoic, 3-chloro

25

1.04 x 10^–4

3.98

Propanoic, 2-(3-chlorophenyl)

25

2.57 x 10^–5

4.59

Propanoic, 2- (4-chlorophenyl)

25

2.46 x 10^–5

4.61

Propanoic, 2-(2-chlorophenyl)

25

2.63 x 10^–4

4.58

Propanoic, 3-hydroxy

25

3.1 x 10^–5

4.51

Propanoic, 2-methyl

18

1.44 x 10^–5

4.84

Propanoic, dimethyl

18

9.4 x 10^–6

5.03

Propanoic, 2-phenyl

25

2.27 x 10^–5

4.64

Propanoic, 3-phenyl

25

4.25 x 10^–5

4.37

iso-Propylbenzoic

25

3.98 x 10^–5

4.40

2-Pyridinecarboxylic

25

3 x 10^–6

5.52

3-Pyridinecarboxylic

25

1.4 x 10^–5

4.85

4-Pyridinecarboxylic

25

1.1 x 10^–5

4.96

Pyrocatechol

20

1.4 x 10^–10

9.85

Quinolinic

25

3 x 10^–3

2.52

Resorcinol

25

1.55 x 10^–10

9.81

Saccharin

18

2.1 x 10^–12

11.68

Suberic

25

2.99 x 10^–5

4.52

Succinic (butanedioic)

25

1

6.89 x 10^–5

4.16

Succinic (butanedioic)

25

2

2.47 x 10^–6

5.61

Sulfanilic

25

5.9 x 10^–4

3.23

a-Tartaric

25

1

1.04 x 10^–3

2.98

a-Tartaric

25

2

4.55 x 10^–5

4.34

meso-Tartaric

25

1

6 x 10^–4

3.22

meso-Tartaric

25

2

1.53 x 10^–5

4.82

Theobromine

18

1.3 x 10^–8

7.89

Terephthalic

25

3.1 x 10^–4

3.51

Thioacetic

25

4.7 x 10^–4

3.33

Thiophenecarboxylic

25

3.3 x 10^–4

3.48

o-Toluic

25

1.22 x 10^–4

3.91

m-Toluic

25

5.32 x 10^–5

4.27

p-Toluic

25

4.33 x 10^–5

4.36

Trichloroacetic

25

2 x 10^–1

0.70

Trichlorophenol

25

1 x 10^–6

6.00

2,4,6-Trihydroxybenzoic

25

2.1 x 10^–2

1.68

Trimethylacetic

18

9.4 x 10^–6

5.03

2,4,6-Trinitrophenol

25

4.2 x 10^–1

0.38

Tryptophan

25

4.2 x 10^–10

9.38

Tyrosine

17

3.98 x 10^–9

8.40

Uric

12

1.3 x 10^–4

3.89

n-Valeric

18

1.51 x 10^–5

4.82

iso-Valeric

25

1.7 x 10^–5

4.77

Veronal

25

3.7 x 10^–8

7.43

Vinylacetic (3-butenoic)

25

4.57 x 10^–5

4.34