Name: gran plot for titration endpoint prediction
Uploaded: 2024-12-05T18:31:57.000Z
Duration: 1 min 7 s
Channel: JoVE

A Gran plot can predict a potentiometric or acid&#8211;base titration&#39;s equivalence volume or end point without actually titrating to the end point.
The usual titration data that tracks the progress of the titration reaction as a function of the titrant&#39;s volume is collected up to a volume less than the equivalence volume and is then converted into a linear form.
After linear regression, the straight line is linearly extrapolated to the x-axis, giving the titrant volume required to reach the equivalence point.
The Gran plot for potentiometric titration is obtained by plotting the volume-corrected base-10 antilogarithm of electrode potential against the titrant volume.
Fitting the best line through the data points and extrapolating to the x-axis predicts the equivalence volume.
Similarly, a weak acid&#8211;strong base titration using the Gran plot equation results in a straight line with a slope of the negative activity-corrected acid dissociation constant and an x-intercept equal to the titrant volume at the end point.

eindpuntvoorspelling: gran plot

End Point Prediction: Gran Plot

Een Gran-plot wordt gebruikt om het equivalentievolume of eindpunt van een potentiometrische of zuur-basetitratie te voorspellen zonder het eindpunt te bereiken. Normaal gesproken worden titratiegegevens verzameld als een functie van het volume van de titrant tot een punt dat kleiner is dan het equivalentievolume en vervolgens omgezet in een lineair formaat. De rechte lijn wordt verlengd tot de x-as, wat het benodigde titrantvolume aangeeft om het equivalentiepunt te bereiken.


Voor potentiometrische titratie wordt de Gran-plot gemaakt door de volumegecorrigeerde basis-10-antilogaritme van het gemeten elektrodepotentiaal (E) uit te zetten tegen het titrantvolume. Het equivalentievolume kan worden voorspeld door de beste lijn door de datapunten te passen en terug te extrapoleren naar de x-as. Op dezelfde manier produceert het gebruik van de Gran-plotvergelijking voor een zwak zuur-sterke basetitratie een rechte lijn, waarbij de helling van de lijn gelijk is aan de negatieve activiteitsgecorrigeerde zuurdissociatieconstante en het x-intercept overeenkomt met het titrantvolume bij het eindpunt.

Eindpuntvoorspelling: Gran Plot

A Gran plot is used to predict the equivalence volume or endpoint of a potentiometric or acid-base titration without reaching the endpoint. Typically, ...

Education

JoVE Core

Analytical Chemistry

Analytische chemie

Unit 1

Electrochemical Analyses and Redox Titration

Elektrochemische analyses en redox-titratie

electrochemical-analyses-and-redox-titration

KEY TERMS AND CONCEPTS

KERNTERMEN EN CONCEPTEN

gran plot for titration endpoint prediction

A Gran plot helps predict the endpoint of a potentiometric or acid-base titration before the endpoint is reached. It uses titration data collected only up to a point that is still below the equivalence volume. The data are then transformed into a straight-line format.

To build the plot, the line is extended to the x-axis. That x-intercept shows the titrant volume needed to reach the equivalence point. In potentiometric titration, the Gran plot uses the volume-corrected base-10 antilogarithm of the measured electrode potential, or E, against titrant volume.

The best-fit line through the data points is then extrapolated back to the x-axis. This gives a prediction of the equivalence volume without continuing the titration to the endpoint. For a weak acid-strong base titration, the Gran plot equation also produces a straight line. In that case, the slope is the negative activity-corrected acid dissociation constant, and the x-intercept matches the titrant volume at the endpoint.

Gran Plot for Titration Endpoint Prediction

gran-plot-for-titration-endpoint-prediction

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end point prediction: gran plot

A Gran plot helps predict the endpoint of a potentiometric or acid-base titration before the endpoint is reached. It uses titration data collected only up to a point that is still below the equivalence volume. The data are then transformed into a straight-line format. To build the plot, the line is extended to the x-axis. That x-intercept shows the titrant volume needed to reach the equivalence point. In potentiometric titration, the Gran plot uses the volume-corrected base-10 antilogarithm of...

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key terms and concepts

Learn how a Gran plot uses titration data below the endpoint to predict equivalence volume. See how the x-intercept reveals the titrant volume needed.

Gran Plot for Titration Endpoint Prediction | JoVE K12

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Gran Plot for Titration Endpoint Prediction

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