Science & Environment
Weak Acid Dissociation (Ka) Calculator
Estimate the pH of a weak acid solution from its concentration and acid dissociation constant Ka.
Your inputs
Change any value to update the result instantly.
Estimated pH
2.872
pKa
4.745
[H+]
0.0013 mol/L
Percent dissociation
1.342 %
Formula and working
[H+] ≈ √(Ka × C); pH = -log[H+]; pKa = -log(Ka)
- 1
Collect the inputs
Initial acid concentration = 0.1 M; Ka (×10⁻⁵) = 1.8
- 2
Apply the formula
[H+] ≈ √(Ka × C); pH = -log[H+]; pKa = -log(Ka)
- 3
Result
Estimated pH = 2.872
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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