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pH, hydrogen ion concentration Calculator

Select Chemical:
Concentration:
pH:
H+ Concentration:



pH calculation formula:
  pH = -log(1/H+)
Where:
H+: Hydrogen ion concentration in the solution

H+ concentration of acid is depended on its pKa, for strong acid like HCl, its pKa=1, thus H+ concentration of 1 M HCl is also 1 M; for weak acid such as acetic acid, its pKa=0.0000175, thus H+ concentration of 1 M acetic acid is: 1 * 0.0000175 = 0.0000175 M



pKa Table of Amino Acids
Name pKa Formula
acetic acid 0.0000175 CH3COOH
arsenic acid 0.006 Ar2O3
arsenious acid 0.0000000006 As2O3
benzoic acid 0.000063 C7H6O2
boric acid 0.00000000064 H3BO3
carbonic acid 0.00000043 H2CO3
citric acid 0.00074 C6H8O7
formic acid 0.000176 CH2O2
hydrocyanic acid 0.00000000072 HCN
hydrofluoric acid 0.00067 HF
hydrosulfuric acid 0.000000091 H2S
hydrochloric acid 1.0 HCl
hypochlorous acid 0.000000011 HClO
perchloric acid 1.0 HClO4
chlorous acid 0.012 HClO2
sulfuric acid 1.0 H2SO4
sulfurous acid 0.013 H2SO3
nitric acid 1.0 HNO3
nitrous acid 0.00051 HNO2
phenol acid 0.00000000011 C6H6O
phenol 0.00000000011 C6H6O
phosphoric acid 0.011 H3PO4
phosphorous acid 0.05 H3PO3
sodium hydroxide 1.0 NaOH
aniline 0.0000000004 C6H5-NH2
ammonia 0.0000175 NH3