What are the component of Karl Fischer?
Karl Fischer reagent consists of iodine, sulfur dioxide, a base and a solvent, such as alcohol. As described below, this method can be used in both volumetric and coulometric titration systems.
What is Karl Fischer coulometric titration?
Karl Fischer titration is a classic titration method in chemical analysis that uses coulometric or volumetric titration to determine trace amounts of water in a sample. It was invented in 1935 by the German chemist Karl Fischer. Today, the titration is done with an automated Karl Fischer titrator.
How much sample is needed for Karl Fischer?
What is the detection limit of the oven method, and how much sample is required to analyze a sample with 10 ppm (mg/L) water content? We recommend having at least 50 µg of water in the sample, if analyzed with coulometry.
What is KF water factor?
The water equivalence factor, F in mg of water per ml of the reagent is given by the expression 0.1566 w/v, where w is the weight, in mg, of the sodium tartrate and v is the volume, in ml, of the reagent required.
What are coulometric methods?
Coulometry is an electrochemical method in which the total charge (the number of coulombs) consumed in the redox conversion of an analyte at an electrode is measured. It is not to be confused with colorimetry, the spectroscopic method.
What is over titrating?
Over-titration is a state where there is more iodine present in the vessel than water (general definition). When over-titration occurs the vessel will become very dark as a result of the abundance of iodine present inside the vessel.
How does a coulometer work?
Coulometric titration is an absolute determination technique in which the mass of a given substance is determined by measuring the quantity of electricity required to electrolyze that substance; it does not necessarily require a standard solution.
What is the use of coulometer?
The silver coulometer is a standard instrument used to determine the mass of silver deposited at a platinum cathode by the passage of an electric current through an aqueous silver nitrate solution.