This method determines the vitamin C concentration in a solution by a redox titration with potassium iodate in the presence of potassium iodide. Vitamin C, more properly called ascorbic acid, is an essential antioxidant needed by the human body (see additional notes).
When iodate ions (IO3 ā ) are added to an acidic solution containing iodide ions (Iā), an oxidation-reduction
occurs;
Due to this reaction the iodine formed is immediately reduced to iodide as long as there is any ascorbic acid present. Once all the ascorbic acid has been oxidised, the excess iodine is free to react with the starch indicator, forming the blue-black starch-iodine complex.
‘This is the endpoint of the titration. The method is suitable for use with Vitamin C tablets, fresh or packaged fruit juices and solid fruits and vegetables.
Read More About Vitamin C Titration University Of Canterbury
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