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Weak Acid / Base Calculator

Equilibrium [H₃O⁺]/[OH⁻], percent ionization and pH for weak electrolytes — approximation checked against the quadratic every time.

Calculator

Results update as you type. Every step of the working is shown below.

Examples:

Result

Enter values above — the answer appears here instantly, with full working.

Formula used

Ka = x²/(C−x) → x ≈ √(Ka·C) when C/Ka ≥ 100

Every result substitutes your values into this relation step by step above.

Assumptions

  • One proton transfer; no other equilibria contribute.
  • The √(Ka·C) shortcut is used ONLY when C/Ka ≥ 100 and x < 5 % of C — otherwise the exact quadratic result is reported.

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