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What is the process known as titration?i
Titration is a laboratory technique by which we can determine the concentration of an unknown reagent using a standard concentration of another reagent that chemically reacts with the unknown. This standard solution is referred to as the "titrant". We have to have some way to determine when the reaction is complete that we are using. This is referred to as the "end point" or more technically the equivalence point. At that point all the unknown has been reacted with the standard titrant and some kind of chemical indicator must let us know when that point has been arrived at.
At the equivalence point:i
Number of equivalent weights of titrant = Number of equivalent weights of unknown
or
(Normality of the titrant)(Volume of titrant required to reach end point) = (Normality of unknown) (Volume of unknown)
Generally we know the Normality of the titrant since it is a standard solution. We also pre-measure the volume of the unknown. We then titrate with the standard from a buret into the container with the measured unknown and the chemical indicator until the indicator either turns color or a precipitate indicates that the end point or the equivalence point has been reached. Having the initial and final readings of the titrant buret gives us the volume of the titrant used. The only unknown in the above equation is the Normality of the unknown.
There are a number of different types of titrations. Some of them are listed below: acid/base Oxidation-Reduction (REDOX) precipitation compleximetric
23-02-2006, 04:03 PM
