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Titration Endpoint

Solve for analyte concentration from titrant volume × normality, with curve preview.

How to use this tool

Work out the concentration of your unknown from a titration, the strength of the titrant and how much of it you ran in to reach the endpoint. Use molarity-with-ratio, or switch to normality if you already work in equivalents.

What to enter

  • Mode: Molarity + ratio (you supply the reaction's mole ratio) or Normality (equivalents already folded in, so no ratio needed).
  • Titrant concentration / normality: the standardised strength of the titrant (M or N).
  • Titrant volume at endpoint: the burette volume where the indicator changed, in mL.
  • Analyte volume: the volume of unknown you titrated, in mL.
  • Mole ratio a : b: analyte-to-titrant stoichiometry (molarity mode only); the preset chips load common pairs like H₂SO₄ ↔ NaOH (1:2).

Reading the result

The headline is the analyte concentration; below it, the moles titrated, with the working formula shown so you can check it.

Worked example

Titrating 25.0 mL of analyte to the endpoint at 23.4 mL of 0.1 M titrant in a 1:1 reaction gives an analyte concentration of about 0.0936 M.

Analyte Concentration

At the endpoint the titrant has exactly consumed the analyte. The headline value is the unknown's concentration; the moles figure is how much analyte was in the aliquot you titrated.

Methodology

At the equivalence point the equivalents of titrant equal the equivalents of analyte. For a reaction with mole ratio a Analyte : b Titrant, the analyte concentration is C₍A₎ = (C₍T₎ · V₍T₎ / V₍A₎) · (a/b). Switching the input to normality removes the ratio term, since normality already folds in equivalents.

Sources

  • Skoog, West & Holler, Fundamentals of Analytical Chemistry, ch. 13–14.
  • Harris, Quantitative Chemical Analysis, titrations.