Acidbase titration curves
This online calculator builds theoretical titration curves for monoprotic acids and bases
The calculator below plots the theoretical titration curve for the acidbase titration of monoprotic acids and bases. It calculates how the curve should look like with KNOWN molarity or molar concentration of titrand, KNOWN molarity of titrant and, in some cases, KNOWN titrand ionization constant (acid dissociation constant for weak acids and base dissociation constant for weak bases).
All formulas for all cases covered by the calculator:
 strong base/strong acid
 strong acid/strong base
 weak base/strong acid
 weak acid/strong base
are described below the calculator.
Titration curves
Definitions
Titration (also known as titrimetry and volumetric analysis) is a common laboratory method of quantitative chemical analysis to determine the concentration of an identified analyte (a substance to be analyzed). A reagent, termed the titrant or titrator, is prepared as a standard solution of known concentration and volume. The titrant reacts with a solution of analyte (which may also be termed the titrand) to determine the analyte's concentration.^{1} An acidbase titration is a quantitative analysis method for determining the concentration of an acid or base by exactly neutralizing it with a standard solution of base or acid having a known concentration.^{2}
A titration curve is a curve in the graph where the xcoordinate represents the volume of titrant added since the beginning of the titration (as the absolute volume or the degree of titration, the ratio of the quantity of added titrant to the quantity of titrand), and the ycoordinate which represents the concentration of the analyte at the corresponding stage of the titration. In an acidbase titration, the ycoordinate of the titration curve represents the pH of the solution.
Points on the acidbase titration curve fall into one of four categories:
 initial pH, degree of titration f = 0
 pH before the equivalence point, 0 < f < 1
 pH at the equivalence point, f = 1
 pH after the equivalence point, f > 1
There are separate formulas for each category.
Notation
Formulas below use the following notations:
 initial molar concentration of the analyte/titrand
 initial molar concentration of titrant
 degree of titration
 water ionization constant , or autoionization constant of water
 ionization constant of analyte/titrand, i.e. acid dissociation constant for weak acids and base dissociation constant for weak bases
Strong base/Strong acid

initial pH

pH before the equivalence point

pH at the equivalence point
 pH after the equivalence point
Strong acid/Strong base

initial pH

pH before the equivalence point

pH at the equivalence point
 pH after the equivalence point
Weak acid/Strong base

initial pH

pH before the equivalence point

pH at the equivalence point
 pH after the equivalence point
Weak base/Strong acid

initial pH

pH before the equivalence point

pH at the equivalence point
 pH after the equivalence point
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