Titration:
Some History
In 1855, the German chemist, Friedrich Mohrn, defined titration
as the "weighing without scale" method, because this
process allows determination of the concentration of a sample
without using complex instrumentation. A manual titration requires
high accuracy and precision, both in the preparation of the material,
and the use of different precisely dosed reagents. The operation
must be repeated at least 3 times to obtain a reliable measured
value. This procedure makes the manual analytical technique very
long and fastidious. On the other hand, the infinite applications
that titration presents, can't be neglected, both for the organic
and inorganic parameters. In some applications, for example in
the food industry, the determination of the content of sulphur
dioxide in must and wine, and the level of acidity in cheese are
still determined manually using the Soxhlet method. See the table
below for other applications.
Food
Industry |
Acidity |
Water
Analysis |
pH |
|
Chloride |
|
Conductivity |
|
pH |
|
Alcalinity |
|
SO²
free and total |
|
Chloride |
|
Sugar |
|
Hardness |
|
Peroxide |
|
COD |
|
Fatty
Acids |
|
Sulfate |
|
Vitamine
C |
|
Ammonia |
|
Acetic
Acid |
|
Fluoride |
|
Relative
Humidity |
|
Nitrate |
Petrochemical |
TAN |
Chemical
Products |
NaOH |
|
TBN |
|
KOH |
|
Br²
Index |
|
Carbonate |
|
Chloride |
|
Ca²+,
Mg²+ |
|
Sulphide |
|
Heavy
Metals |
|
Mercaptan |
|
Ag+ |
Pharmaceutical |
Titration
with HClO4 |
Plating
Industry |
Ag+ |
|
Ca²+,
Mg²+ |
|
Ni²+ |
|
Carbonate |
|
Zn²+ |
|
Enzymatic
Determinations |
|
Cr³+,
Cu²+, etc |
Titration,
moreover, can be of different types: potentiometric, amperometric,
spectrophotometric, etc., depending on the properties of the monitored
system. The growing need for faster results, has lead HANNA instruments®
to develop the new titrators HI 901 and HI 902, two instruments
that permit the automation of the titration procedures, while
providing quick and reliable data.
|