NAVI F-52, Instruction Manual

Page: 252 / 270

Chapter 16 Reference
16.4 Conductivity measuring
F-52, 53, 54, 55 239
16.4 Conductivity measuring
●
Electrode sensitivity check
The cell constant of a conductivity electrode may vary, depending on the sample solution.
Check the cell constant by measuring conductivity using the following solutions, at least once
every three months.
Prepare the potassium chloride standard solution (KCl 0.01 mol/L) by the below procedure.
In addition, if an error of 5 % of more compared with the above values occurs, calibrate the
cell constant.
●
Preparing potassium chloride standard solution
How to prepare solution
Dry the potassium chloride powder (superior quality commercial potassium chloride or bet-
ter) for two hours, at 105 ºC, then cool it in a desiccator. Measure out the above-listed amount
of potassium chloride into a beaker and dissolve it in distilled water. Then, pour into one liter
volumetric flask and add distilled water until the indication line.
Cell
constant
Corresponding
model
KCl
standard
solution
Soluti
on
temp.
Conductivity
value
1000 m
-1
(10 cm
-1
)
#3553-10D 0.1 mol/L
0
℃ 713 mS/m
(7.13 mS/cm) 7.4365 g Dissolve capacity-
weighed KCL and
put it into a mea-
suring flask (1 lit-
ter), and then add
distilled water up to
the marked line.
18
℃ 1.117 S/m
(11.17 mS/cm)
25
℃ 1.286 S/m
(12.86 mS/cm)
100 m
-1
(1 cm
-1
)
#3552-10D 0.01 mol/L
0
℃ 77.4 mS/m
(0.774 mS/cm) 0.7440 g
18
℃ 122.0 mS/m
(1.220 mS/cm)
25
℃ 140.9 mS/m
(1.409 mS/cm)
10 m
-1
(0.1 cm
-1
)
#3551-10D 0.001 mol/L 25 ℃ 14.7 mS/m
(147
μ
S/cm)
− Scoop 100 mL of
0.01 mol/L stan-
dard solution with a
transfer pipet and
put it into a mea-
suring flask (1 lit-
ter), and then add
distilled water up to
the marked line.