15
14
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