The activity is a measure of the amount of
ions chemically active in a concentration of the ions in solution.
This means that the participation of ions in a chemical reaction is
not only determined by the concentration but also by the presence of
other ions in the solution. In concentrated solution the activity of
the ions is considerably less than the total concentration.
The activity coefficient (F) shows the
ratio between the active concentration and the total concentration.
F = active concentration / total concentration
Anions are negatively charged ions, e.g. Cl-,
NO-, OH-.
- Automatic Temperature
Compensation:
Automatic control of the sensitivity of
the measuring converter to compensate for the reaction of the chemical
equilibrium.
The capacity of a conductor is the
quotient of the charge and, as a result of this charge, the generated
voltage of a conductor.
The cell constant of a conductivity
measuring cell is determined by the ratio of the distance between the
electrodes and the area of the electrodes.
C = L / O (cm -1; m -1)
The concentration of a solution is
determined by the quantity of matter dissolved per volume or per
weight of the solution.
- Grams per dm3 (liter)
or kilograms/m3:
The weight in grams per dm3 (liter) solution.
- Grams per kilogram:
The weight in grams of matter per kilogram of solution.
- Milligrams per kilogram:
The weight in milligrams of matter per kilogram of solution.
NOTE: This is commonly expressed as ppm (parts per
million).
- Micrograms per kilogram:
The weight in micrograms of matter per kilograms of solution.
NOTE: This is commonly expressed as ppb (part per billion).
- Mol per liter or molar:
The weight in grams corresponding with the molecular weight per
liter of solution.
- Mol per kilograms or molar:
The weight in grams corresponding with the molecular weight per
kilograms of solution.
- Weight percents:
The weight of dissolved matter per 100 grams of solution.
The name of a solution after condensation
of steam.
The number of the ratio between the
current value and the area of the conductor.
Dissociation is separating into positive
and negative ions.
The number gives the ratio between the
concentration of the separated ions in a matter and the concentration
of the unseparated matter.
AB = A / B
K = [A] [B] / [AB]
An electrolyte is a matter that separates
ions in an aqueous solution. Weak electrolytes partly dissociate,
strong electrolytes dissociate almost completely.
The equivalent conductivity of a solution
is the specific conductivity of this solution when 1 kilogram
equivalent/m3 or 1 gram equivalent/dm3 of the
solid matter is dissolved.
Hydration is the surrounding of ions with
molecules of water.
The strength of ions in a solution is
determined by both the concentrations of the ions in the solution and
the nature of these ions. The strength of ions determines the activity
of each ion in the solution. In an equation, the strength of ions is:
I = 0.5 (C)(Z2)
C = concentration
Z2 = square of the charge of the ion
Screening of the electrodes of a
conductivity measuring cell, e.g. by an incomplete discharge of ions.
- Rhondinising of Electrodes:
The addition of a rhondium layer on the
electrode surfaces for the increase of these surfaces.
The number of the ratio between the
conductivity value at the process temperature and the conductivity
value at the reference temperature.
Indicates the temperature influence on the
chemical equilibrium (e.g. dissociation) of the solution.
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Instruments Pte Ltd. marketing@eutechinst.com
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