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Titrator Concentration Is Constantly Changing
Jul 01, 2017

The principle of the potential method is: select the appropriate indicator electrode and the reference electrode and the measured solution to form a working battery, with the addition of the titrant, due to chemical reactions, the measured concentration of ions continue to change,Titrator thus indicating the electrode potential With the change. In the vicinity of the titration end point, the measured ion concentration changes, causing the electrode potential of the jump, therefore, according to the electrode potential of the jump can determine the end point of the titration.

Instrument power meter and titration system two parts, electricity meter using electronic amplification control circuit, the indicator electrode and the reference electrode potential with a preset terminal potential compared to the difference between the two signals after amplification control titration System drip rate. After reaching the end preset potential, the titration stops automatically. The instrument is divided into two parts: electric meter and titration system.

A number of titrator instrument in the measured solution before the first calibration, in continuous use, the calibration once a day can be calibrated by a point calibration method and two-point calibration method, conventional measurement using a little calibration method, accurate measurement Using two-point calibration method. The instrument can be used for various types of potentiometric titration, the user according to the different electrodes, insert the rear panel of the electrode jack, if the electrode can not be directly inserted into the Q9 jack, you can use the instrument to provide Q9 plug; Alligator can hold the electrode head.

When titration is performed on a number of titrators, a reference electrode is inserted into the measured solution, and one indicator electrode constitutes a working battery. With the addition of the titrant, due to the chemical reaction 2. The measured ion concentration is constantly changing, indicating that the potential of the electrode also changes accordingly. A potential jump occurs near the waiting point. So the measurement of working battery 3. electromotive force changes can be determined titration end point.

A number of titrator titration of the basic instrument device, including burette, titration cell, indicating electrode, reference electrode, stirrer, measured electromotive force of the instrument.

How does titration determine the end point of titration? The method of determining the curve with the drawing potential.

The titration curve is the graph of the electrode potential (battery electromotive force) E plotting the volume of the standard solution.

According to the method of mapping, there are three types of potentiometric titration curve, E-V curve, ordinary potential titration curve, inflection point e is equivalent point.

Determine the inflection point, make two with the titration curve tangent 45 ° oblique line, bisector and curve of the intersection point that is inflection point.