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FC300 Combination Sodium Electrode
FC300 Combination Sodium Electrode
FC300 Combination Sodium Electrode
FC300 Combination Sodium Electrode
FC300 Combination Sodium Electrode
I .
I .I.
I .
I .
Introduction
Introduction
Introduction
Introduction
Introduction
The Hanna FC300 Sodium electrode is a glass combina-
tion ion selective electrode designed for the measurement
of sodium ions in aqueous solutions such as water, food,
beverages, wine, beer and soil.
The electrode utilizes a special glass membrane that is
selective to sodium ions. The internal reference electrolyte
chamber is refillable.
II
IIII
IIII. Specifications
Specifications
Specifications
Specifications
Specifications
Type:
Glass combination ISE with
Ag/AgCl reference
Ion measured:
Sodium (Na
+
)
Measurement range:
1M to 1X 10
-5
M
39100 to 0.039ppm
Operating Temperature:
0-80
°
C
Operating pH:
9.75-14 pH
Dimensions:
12 mm (OD) x 120 mm
insertion (0.47
”
x 4.72
”
)
Connection:
BNC Plug
Wetted Materials:
glass, ceramic
III.
III.
III.
III.
III. Theory of Operation:
Theory of Operation:
Theory of Operation:
Theory of Operation:
Theory of Operation:
The FC300 sodium electrode is a potentiometric device
used for the rapid determination of free sodium ions in
water, soft drinks, beer, wine, and soils. The electrode
functions as a sensor or ionic conductor. The FC300 is a
combination electrode that does not require a separate
reference electrode to complete its electrolytic circuit. The
selective glass membrane blown on the tip of the sensor
exchanges ions with the sample solution which produces a
voltage on the surface of the membrane. This creates a
charge imbalance between the test solution and internal
cell of the sensor. This exchange on the external surface
produces a voltage that changes in response to the sample
’
s
ion activity. When the ionic strength of the sample is fixed,
and hydrogen ions are eliminated, the voltage is propor-
tional to the concentration of sodium ions in solution. The
sensor follows the Nernst Equation:
E = E
a
+ 2.3 RT/nF log A
ion
E = observed potential
E
a
= Reference and fixed internal voltages
R = gas constant (8.314 J/K Mol)
n= Charge on ion (equivalents/mol) (1+)
A
ion
= ion activity in sample
T = absolute temperature in
K
F = Faraday constant (9.648 x 10
4
C/equivalent)
Interference:
Ratio of interfering ion to Na
+
must be below
.0001 for H
+
1 for K
+
Note: other monovalent
cations may also
increase sodium
readings.