Titration Calculator (Unknown Concentration)
Titration calculator: unknown concentration from the titrant volume at the endpoint, with any mole ratio.
Ca · Va · ν = Ct · Vt
How to use this calculator
- Choose the quantity you want under “Solve for”.
- Type the known values and pick their units: any combination works.
- The result updates as you type. Open “Show the steps” to see the substitution.
At equivalence, moles of titrant = ν × moles of analyte: C_t·V_t = ν·C_a·V_a.
Use ν = 1 for HCl + NaOH and ν = 2 for H₂SO₄ titrated with NaOH.
Formula
Ca · Va · ν = Ct · Vt
| Symbol | Quantity | Units |
|---|---|---|
| Ct | Titrant concentration | mol/L, mmol/L, µmol/L, nmol/L, mol/m³ |
| Vt | Titrant volume at endpoint | L, mL, µL, m³, dm³, cm³, gal, gal (UK), qt, pt, cup, fl oz, ft³, in³ |
| ν | Mol titrant per mol analyte (e.g. 2 for H₂SO₄ + NaOH) | — |
| Va | Sample volume | L, mL, µL, m³, dm³, cm³, gal, gal (UK), qt, pt, cup, fl oz, ft³, in³ |
| Ca | Sample concentration | mol/L, mmol/L, µmol/L, nmol/L, mol/m³ |
Worked example
Given: Ct = 0.1 mol/L · Vt = 25 mL · ν = 1 · Va = 20 mL
Ca = Ct Vtν Va
Result: Ca = 0.125 mol/L
Frequently asked questions
25 mL of 0.1 M NaOH neutralise 20 mL of HCl. Concentration?
0.125 M.