Thermo Orion Star, Руководство пользователя

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Thermo Electron Corporation IX-1 Orion Star Series Meter
Chapter IX
Conductivity Technique
Definitions of Terms
Before proceeding with instrument setup, the user is advised to become familiar
with the following concepts:
• Conductivity Linear Temperature Compensation is a default setting in the
Orion Star Series meters .
• The conductivity of a solution with a specific electrolyte concentration changes
with temperature . The relationship of the change in conductivity as a function of
temperature is described by a solution’s temperature coefficient . Temperature
coefficients vary with each solution . Some examples are shown in the table
which follows . This meter uses 2 .1%/˚C as the default linear temperature
coefficient, which is representative of many aqueous samples, to compensate
for temperature changes . The meter has an adjustable temperature coefficient of
0 .0 to 10 .0%/˚C .
Table IX-1 –
Typical Temperature Coefficients Between 25 and 50 ºC (Percent
change of Conductivity per ºC)
Solution %/˚C
Ultrapure Water 4.55
Salt (NaCl) Solutions 2.12
5% NaOH 1.72
Dilute Ammonia 1.88
10% HCl 1.32
5% Sulfuric Acid 0.96
98% Sulfuric Acid 2.84
Sugar Syrup 5.64