Accessories – Hanna Instruments pH 209 User Manual
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ACCESSORIES
pH CALIBRATION SOLUTIONS
HI 70004P pH 4.01 buffer solution, 20 mL sachet, 25 pcs
HI 70007P pH 7.01 buffer solution, 20 mL sachet, 25 pcs
HI 70010P pH 10.01 buffer solution, 20 mL sachet, 25 pcs
HI 7004L pH 4.01 buffer solution, 500 mL
HI 7006L pH 6.86 buffer solution, 500 mL
HI 7007L pH 7.01 buffer solution, 500 mL
HI 7009L pH 9.18 buffer solution, 500 mL
HI 7010L pH 10.01 buffer solution, 500 mL
HI 8004L pH 4.01 buffer solution in FDA bottle, 500 mL
HI 8006L pH 6.86 buffer solution in FDA bottle, 500 mL
HI 8007L pH 7.01 buffer solution in FDA bottle, 500 mL
HI 8009L pH 9.18 buffer solution in FDA bottle, 500 mL
HI 8010L pH 10.01 buffer solution in FDA bottle, 500 mL
ELECTRODE STORAGE SOLUTION
HI 70300L Storage solution, 500 mL
HI 80300L Storage solution in FDA bottle, 500 mL
ELECTRODE CLEANING SOLUTIONS
HI 70000P Electrode rinsing solution, 20 mL sachet, 25 pcs
HI 7061L General cleaning solution, 500 mL
HI 7073L Protein cleaning solution, 500 mL
HI 7074L Inorganic cleaning solution, 500 mL
HI 7077L Oil & Fat cleaning solution, 500 mL
HI 8061L General cleaning solution in FDA bottle, 500 mL
HI 8073L Protein cleaning solution in FDA bottle, 500 mL
HI 8077L Oil & Fat Cleaning solution in FDA bottle, 500 mL
ELECTROLYTE SOLUTIONS
HI 7071
3.5M KCl + AgCl electrolyte solution, 4 x 30 mL, for
single junction electrodes
HI 7072
1M KNO
3
electrolyte solution, 4 x 30 mL
HI 7082
3.5M KCl electrolyte solution, 4 x 30 mL, for double
junction electrodes
HI 8071
3.5M KCl + AgCl electrolyte solution in FDA bottle, 4 x
30 mL, for single junction electrodes
HI 8072
1M KNO
3
electrolyte solution in FDA bottle, 4 x 30 mL
HI 8082
3.5M KCl electrolyte solution in FDA bottle, 4 x 30 mL,
for double junction electrodes
Alkaline Error
1.0 Mol L
-1
Na
+
0.1 Mol L
-1
Na
+
Sodium Ion Correction for the Glass at 20-25°C
Concentration
pH
Error
13.00
13.50
14.00
12.50
13.00
13.50
14.00
0.10
0.14
0.20
0.10
0.18
0.29
0.40
TEMPERATURE-RESISTANCE CORRELATION
FOR HANNA pH SENSITIVE GLASS
The resistance of glass electrodes partially depends on the temperature.
The lower the temperature, the higher the resistance. It takes longer time
for the reading to stabilize if the resistance is higher. In addition, the
response time will suffer to a greater degree at temperatures below 10°C.
Since the resistance of the pH electrode is in the range of 200 Mohm,
the current across the membrane is in the pico Ampere range. Large
currents can disturb the calibration of the electrode for many hours.
For these reasons high humidity environments, short circuits and
static discharges are detrimental to a stable pH reading.
The pH electrode's life also depends on the temperature. If constantly
used at high temperatures, the electrode life is drastically reduced.
Typical Electrode Life
Ambient Temperature
1- 3 years
90 °C
Less than 4 months
120°C
Less than 1 month
High concentrations of sodium ions interfere with readings in alkaline
solutions; the pH at which the interference starts to be significant
depends upon the composition of the glass. This interference is the
alkaline error and causes the pH to be underestimated. Hanna's glass
formulations have the indicated characteristics.
-20 -20
-10
0 +10+20 +30+40 +50+60+70 +80+90
° C
-10
-10
Ω
-10
-10
-10
-10
Ω
2x10
9
1x10
9
2x10
8
1x10
8
2x10
7
1x10
7
-20 -10 0
+
10
+
20
+
30
+
40
+
50
+
60
+
70
+
80
+
90
°C