Acid Dissociation (Ka & pKa)Chemistry
Acid Dissociation Constant (Ka & pKa) & Solution pH Calculator
Calculate Ka, pKa, hydronium concentration [H+], equilibrium solution pH, and percent ionization for weak monoprotic acids using quadratic ionic equilibrium.
Calculated Result
Solution Equilibrium pH
0pH
Calculator Inputs
-
Quick select:
M
Quick select:
Solution Equilibrium pH
0pH
Hydronium Concentration [H+] (M)
0 M
Percent Ionization (%)
0 %
Weak Ionization (< 5%): Satisfies the analytical 5% approximation rule; vast majority of acid remains intact as undissociated molecules.
Acid Dissociation Equilibrium Profile
pH Value
0 pH(0%)
Ionization %
0 %(0%)
Standard analytical chemistry tool for aqueous weak acid dissociation equilibrium.
Calculation Methodology
pKa = -log10(Ka) and Ka = 10^(-pKa). Equilibrium expression: Ka = [H+]^2 / (C - [H+]). Quadratic solution: [H+] = (-Ka + sqrt(Ka^2 + 4*Ka*C)) / 2. pH = -log10[H+]. % Ionization = ([H+] / C) * 100%.
Frequently Asked Questions
Lower or more negative pKa values signify stronger acids that donate protons more readily in water; strong mineral acids like HCl have pKa < 0, while weak organic acids have pKa 3 to 10.
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