Table of Acid and Base Strength

 

 

Ka

Acid

Base

Name

Formula

Formula

Name

Large

Perchloric acid

HClO4

ClO4 -

Perchlorate ion

3.2 * 109

Hydroiodic acid

HI

I-

Iodide

1.0 * 109

Hydrobromic acid

HBr

Br-

Bromide

1.3 * 106

Hydrochloric acid

HCl

Cl-

Chloride

1.0 * 103

Sulfuric acid

H2SO4

HSO4 -

Hydrogen sulfate ion

2.4 * 101

Nitric acid

HNO3

NO3 -

Nitrate ion

--------

Hydronium ion

H3O+

H2O

Water

5.4 * 10-2

Oxalic acid

HO2C2O2H

HO2C2O2-

Hydrogen oxalate ion

1.3 * 10-2

Sulfurous acid

H2SO3

HSO3 -

Hydrogen sulfite ion

1.0 * 10-2

Hydrogen sulfate ion

HSO4 -

SO4 2-

Sulfate ion

7.1 * 10-3

Phosphoric acid

H3PO4

H2PO4 -

Dihydrogen phosphate ion

7.2 * 10-4

Nitrous acid

HNO2

NO3 -

Nitrite ion

6.6 * 10-4

Hydrofluoric acid

HF

F -

Fluoride ion

1.8 * 10-4

Methanoic acid

HCO2H

HCO2 -

Methanoate ion

6.3 * 10-5

Benzoic acid

C6H5COOH

C6H5COO-

Benzoate ion

5.4 * 10-5

Hydrogen oxalate ion

HO2C2O2-

O2C2O2 2-

Oxalate ion

1.8 * 10-5

Ethanoic acid

CH3COOH

CH3COO

Ethanoate (acetate) ion

4.4 * 10-7

Carbonic acid

CO3 2-

HCO3 -

Hydrogen carbonate ion

1.1 * 10-7

Hydrosulfuric acid

H2S

HS-

Hydrogen sulfide ion

6.3 * 10-8

Dihydrogen phosphate ion

H2PO4 -

HPO4 2-

Hydrogen phosphate ion

6.2 * 10-8

Hydrogen sulfite ion

HS-

S2-

Sulfite ion

2.9 * 10-8

Hypochlorous acid

HClO

ClO-

Hypochlorite ion

6.2 * 10-10

Hydrocyanic acid

HCN

CN-

Cyanide ion

5.8 * 10-10

Ammonium ion

NH4 +

NH3

Ammonia

5.8 * 10-10

Boric acid

H3BO3

H2BO3 -

Dihydrogen carbonate ion

4.7 * 10-11

Hydrogen carbonate ion

HCO3 -

CO3 2-

Carbonate ion

4.2 * 10-13

Hydrogen phosphate ion

HPO4 2-

PO4 3-

Phosphate ion

1.8 * 10-13

Dihydrogen borate ion

H2BO3-

HBO3 2-

Hydrogen borate ion

1.3 * 10-13

Hydrogen sulfide ion

HS-

S 2-

Sulfide ion

1.6 * 10-14

Hydrogen borate ion

HBO3 2-

BO3 3-

Borate ion

---------

water

H2O

OH-

Hydroxide

 

 

1. Strong acids are listed at the top left hand corner of the table and have Ka values >1
2. Acid with values less than one are considered weak.
3. The strong bases are listed at the bottom right of the table and get weaker as we move to the top of the table.